2005 MK4 TDI Wagon - Really Long Start - Confused By Dash Lights

[05TurboWagon]

So, Friday I started having issues with really long/hard starts. I recorded a video Friday that I was going to post. Initially thought the issue was my battery due to the odd dash lights. However, after testing the battery, it is good.

Now, I'm thinking it could be a fuel line leak allowing air intrusion causing fuel to drain through the lines back to the tank. So far I have not found the leak. I have a new Tandem pump that I planned on replacing (had this issue for a bit almost a year ago).

What is new is the lights on the dash when I attempt to start the vehicle. The EPS light comes on as does the ABS light (sometimes). Do they suggest something I could be overlooking?

I get no codes for the vehicle. I am not a vagcom/rosstech expert. I am reading through the hardstart/long start/no start stickies, but have yet to find a solution.

 

[DivineChaos]

Have you checked your grounds? I had some erroneous lights and odd behavior due to a loose ground

 

[05TurboWagon]

Have you checked your grounds? I had some erroneous lights and odd behavior due to a loose ground

So far I have found no faulty grounds. What's funny is that they pop on while attempting to start. Once the vehicle is running, they go away.

 

[DivineChaos]

Well if no codes.. and yes I'd say your fuel is draining back. Any injector lines leaking? Could be the check ball in your lift pump. Fuel filter changed recently? One of the filter lines loose?

 

[05TurboWagon]

I have not seen any injector lines leaking. I noticed some sort of leak in the front passenger side area of the engine compartment. I had some other issues a while back that I fixed so I'm not sure if this is residual. I have not changed the fuel filter recently nor have I found any leaks in the hoses in that area. However, I have a new fuel filter that I was going to install tomorrow. I also picked up some diesel Purge, so I figured that was a good time to clean the fuel system and replace the filter.

However, I have not checked the check valve in the lift pump. I'm trying to finish putting away stuff in my garage so pull the wagon in and do some more work. It's starting to get cold outside LOL

 

[KrashDH]

You said you "checked" the battery. How did you check it? If you're just checking voltage, that's not going to tell you anything about it's health. You need to load test it. Let the car sit (best overnight). Turn on accessories in the car, have someone check the voltage drop on the battery during cranking. I can't remember off the top of my head, but I think you want to be above 9.5 V give or take.

Hard starting and weak starting are 2 different things. Erratic behavior in the cluster screams grounding or battery issue.
If you indeed have a properly charged battery that passes load testing, then I'd say move on to fuel issues. Don't rule out grounds though.

 

[05TurboWagon]

You said you "checked" the battery. How did you check it? If you're just checking voltage, that's not going to tell you anything about it's health. You need to load test it. Let the car sit (best overnight). Turn on accessories in the car, have someone check the voltage drop on the battery during cranking. I can't remember off the top of my head, but I think you want to be above 9.5 V give or take.

Hard starting and weak starting are 2 different things. Erratic behavior in the cluster screams grounding or battery issue.
If you indeed have a properly charged battery that passes load testing, then I'd say move on to fuel issues. Don't rule out grounds though.

Loaded tested the battery several times. The battery is still good; however, I'm doing a refresh of major parts, so that is definitely on the list. I don't like waiting until things to go bad... but it sometimes happens.

It looks like the issue might actually be my lift pump... so glad I filled up right before things went wonky. I'll be picking up a few diesel cans and a fuel transfer pump to empty the tank. I figure, if I'm going to be replacing the pump, I might as well inspect/clean the tank while I'm at it.

What's funny is I have discovered a new leak... the cooler on the fuel return (hose not cooler itself). So, more fun stuff to replace. lol

 

[KrashDH]

Loaded tested the battery several times. The battery is still good; however, I'm doing a refresh of major parts, so that is definitely on the list. I don't like waiting until things to go bad... but it sometimes happens.

It looks like the issue might actually be my lift pump... so glad I filled up right before things went wonky. I'll be picking up a few diesel cans and a fuel transfer pump to empty the tank. I figure, if I'm going to be replacing the pump, I might as well inspect/clean the tank while I'm at it.

What's funny is I have discovered a new leak... the cooler on the fuel return (hose not cooler itself). So, more fun stuff to replace. lol

Cool right on. I had my last battery literally fail on me overnight. No slow weird electrical problems or anything. Started fine all day, then sat overnight, didn't even have enough juice to turn the car over in the morning. Tested it, charged it, tried again, wouldn't turn it over. FIrst time I've had one completely go out on me without showing me any weird electrical gremlins first

 

[oilhammer]

Just some battery tips:

Nominal voltage on a 12v battery is 12.6vDC (6 cells, 2.1v each). Normal, acceptable cranking voltage is 10.5v. Many ECUs (which includes, but is not limited to, the Instrument cluster) start to lose their mojo around 9.6v. Which gives you, under "normal" conditions, only a .9v margin. Less than a volt. Not much. Our diesels probably cannot tolerate a .7v difference on cold starts without some strangeness possible happening.

The way I like to check a battery is by measuring that voltage at at least two places on each leg (positive and negative). This allows you to also find any voltage drops. I've found a 10.5v cranking on the battery posts, but then only 8.8v at the starter, because the ground wire to the engine/trans had corroded so bad under its crimped end that half the individual strands were simply gone. It looked fine, the battery tested fine (and it was), but the ground cable's inability to allow the starter to get all its juice was causing a slow crank, and since it was drawing more amps it was getting the cable hot AND causing the clock and odometer to zero out every time the car was cranked. The engine started every time (barely), but it was clearly an issue.

So never assume just because the battery itself checks "ok" that all the connections are secure.

 

[05TurboWagon]

Just some battery tips:

Nominal voltage on a 12v battery is 12.6vDC (6 cells, 2.1v each). Normal, acceptable cranking voltage is 10.5v. Many ECUs (which includes, but is not limited to, the Instrument cluster) start to lose their mojo around 9.6v. Which gives you, under "normal" conditions, only a .9v margin. Less than a volt. Not much. Our diesels probably cannot tolerate a .7v difference on cold starts without some strangeness possible happening.

The way I like to check a battery is by measuring that voltage at at least two places on each leg (positive and negative). This allows you to also find any voltage drops. I've found a 10.5v cranking on the battery posts, but then only 8.8v at the starter, because the ground wire to the engine/trans had corroded so bad under its crimped end that half the individual strands were simply gone. It looked fine, the battery tested fine (and it was), but the ground cable's inability to allow the starter to get all its juice was causing a slow crank, and since it was drawing more amps it was getting the cable hot AND causing the clock and odometer to zero out every time the car was cranked. The engine started every time (barely), but it was clearly an issue.

So never assume just because the battery itself checks "ok" that all the connections are secure.

Oilhammer, thanks dude! That's a good thing to do, that I didn't think of! I found found a fuel line leak that I need to address. One of those PVC lines running from the pass-rear of the engine compartment, through the frame and towards the back is leaking. I'm looking for replacement lines, but haven't found anything yet. I also think that the check valve in my lift pump is shot, so I am replacing the whole unit.

When I tested the battery while cranking, I was getting 10.2 volts give or take.

 

[JB05]

idparts sells fuel line in one meter lengths.

 

[05TurboWagon]

idparts sells fuel line in one meter lengths.

Yep, I have 15 feet of soft tubing to replace everything in the engine compartment (I'm not paying 300+ dollars for pre and post filter formed lines). I was looking for something clear to go from the the fuel filter, tank draw and return, to the hard line on the engine. I have seen people suggesting nylon. What I am having trouble with is the hard line (pastic, pvc, or whatever it is) that runs from the passenger rear of the engine compartment through the frame to the return line cooler and to the tank. I was looking for premade line, but I am not finding anything. Now I'm looking for semi-rigid tubing and the appropriate fittings.

 

[pedroYUL]

Dash lights do flash if you have extended cranking with no solid start (ask me how I know).

Did you change/inspected the tandem pump? They love to leak.

After watching the video: it does seem that engine is not turning fast enough, charge your battery well, and maybe R&R/replace your starter. I was surprised to see how fast my BEW started once I changed the tired Bosch for a brand spanking new Valeo starter.

 

[DuraBioPwr]

Tach is not moving while cranking. Might be your crank position sensor. I have had multiple issues with mine. If no signal from crank sensor then it does exactly as its doing with the lights and other stuff. Should throw a P0700 I believe if you crank it enough times with no start.

 

[05TurboWagon]

Dash lights do flash if you have extended cranking with no solid start (ask me how I know).

Did you change/inspected the tandem pump? They love to leak.

After watching the video: it does seem that engine is not turning fast enough, charge your battery well, and maybe R&R/replace your starter. I was surprised to see how fast my BEW started once I changed the tired Bosch for a brand spanking new Valeo starter.

This same issue happened early this year, but straightened itself up (It was balls ass cold as well). I originally suspected the tandem pump, based on what I was seeing, the sounds I was hearing w/ respect to location. I picked up a new tandem pump, then the issue fixed itself. When this started happening again, to verify whether or not the issue was the tandem pump, I had an idea. I had picked up 10 or 20 cans of Diesel Purge on sale somewhere, but never run them through the system (bad me). I thought, two birds - one stone. I built built a reservoir can with filters on the lines for source and return lines. The engine started right up, thinking that Diesel Purge simply has a high cetane rating, I replaced the fuel filter, purged the source line from the lift pump and reconnected the lines. She started right up like an angry rampaging she-beast, after walking on her just mopped floors. She continued running like a champ. I took it out and ran it through the paces. When I tried to start her up the following moring (roughly same temp), same issues as in the video. I purged the air in the source line, reconnected, and she started up immediately.

I checked around the tandem pump for leaks, and issues in the coolant lines (lost a bit of coolant over the passed few months), but I find now issues with either rags or inspection mirrors, other than being dirty. At this point, I may replace the tandem pump just because I have a new one; but I am on the fence, thinking it would be better to wait until it actually goes out or starts leaking. The fuel lines are not in the greatest condition, so I have started replacing them. I didn't want to pay 300+ dollars for pre and post filter prebent lines, so I'm simply running 5/16 fuel line (hopefully the molded lines are not needed for a specific reason). I would love to install clear lines, but I am still unsure as to whether or not I should go with tygon, viton, neoprene, etc to be diesel safe, specifically biodiesel (I would like to have the option to run it later).

While replacing the lines from driver side to passenger side, I noticed the fuel lines running from the pass-firewall area down the frame. I have found what looks like a drip/leak close to where the lines transition to under body (I'll take a pic when I get home). I am looking for either the right tubing and fittings to replace this line, or a factory set (makes my life easy for a little money) to replace these lines. However, the leak does not seem to be sufficient enough to allow as much fuel to leak back to the tank as what I'm seeing (based on prime time when I disconnect source line from the fuel filter). Although this leak needs to get fixed, I don't think it is the source of my problem (but could be, so replacement/patch is a good idea anyway). I believe the check valve in my lift pump is shot. I have a new complete unit. I am trying to figure out how much fuel I need to drain from the tank before pulling the fuel pump. My driveway is at an angle and the tank is rather full. I am going to hotwire the existing pump to drain some fuel out of the tank (I figured 5 gal should be good, but have another can and can do 10 (I'm so happppy I filled up right before this happened). She's parked in my driveway at an upward angle so, better safe than sorry, but I could roll down the drive way to a more level surface. It is balls ass cold, but one way or another, I want to get this done tonight. If I can get the pump changed and line bled this evening, it should have enough time to sit overnight so that I can attempt to start it in the morning; that should tell me if my issue is the check valve in the lift pump or if it is the leak in the line.

 

[05TurboWagon]

For the sake of posterity and any poor fool that happens upon this thread while actually using the search function... I thought I'd update everyone on my progress, fixes, etc. As it seems, I have had a myriad of issues all revolving around fuel delivery. This is what I have done over the past week and a half or so, as time permitted.

Lift Pump:

Although the lift pump was still "good", it was pushing just above the required fuel pressure; however, the check valve was shot. After replacing the lift pump, fuel delivery was better, throttle response stronger, but I still had a LONG start after it sat over night. Turning the wagon on and off a few times to build fuel pressure helped, but the crank time stick sucked ass. What that meant is that it still had air intrusion. Let's look at soft fuel lines...

Fuel Lines:

Most of the fuel lines were hit with good'ol AZ dry rot. I either replaced or trimmed the dry rotted lines for the low pressure and return lines. I used off the shelf l I went with off the shelf line... I'm not paying 160 bucks a set for the pre and post filter lines... seems overly spendy and dumb. The few lines under high pressure seem to all be good. They were coated with a good layer of oil/grime which seemed to do a great job of protecting them. Still had to switch the wagon on and off to prime the lines again, followed by long start. Next up, Tandem pump.

Tandem Pump:

There are only few more things I can think of that would allow air intrusion (minus injector seals... but one would know of those were bad fairly easily). I thought my tandem pump was good. As it turns out, the gasket was leaking both oil and fuel! EXCITING! I had bought a tandem pump earlier this year; I had similar starting issues, but then they went away for the most part, but I developed a magical oil leak. I say magical because I couldn't find it after crawling all over, in, and around the engine bay. It currently seems like both the oil, fuel, and air intrusion leak have been fixed. I let her sit for a few ours after getting things primped and testing. I'm running the long test tonight. I will try starting her up in the morning and see how it goes. However, so far so good. I will say that I had to replace coolant when changing the tandem pump; I couldn't get the tandem pump out without removing the coolant temp sensor assembly. So... if you figure out a way, cool... maybe next, return line cooler or lines going back to it...


Aside from the fuel system, I did replace the starter. The starter was weak. I was getting a weird "whirring" sound if the wagon had not been started up within a few hours. The bendix was getting stuck. So... new starter... Valeo seems to work well; so far, I like it.

I'll update tomorrow to see what could next.

 

[irvingj]

Thanks for that update. I also have an 05 wagon, and occasionally get an annoyingly long crank before starting.... and other times it starts up within 1-2 seconds. I understand the lift pump in the tank (and that's on the list), but where is the "tandem pump"? -- I currently have "only" 152K on my little blue beast. Don't know a whole lot about my BEW --still learning-- because I basically haven't had much trouble with it.

 

[05TurboWagon]

Thanks for that update. I also have an 05 wagon, and occasionally get an annoyingly long crank before starting.... and other times it starts up within 1-2 seconds. I understand the lift pump in the tank (and that's on the list), but where is the "tandem pump"? -- I currently have "only" 152K on my little blue beast. Don't know a whole lot about my BEW --still learning-- because I basically haven't had much trouble with it.

The tandem pump is on the right side of the engine. It serves as the secondary fuel pump (high pressure) as well as the vacuum pump.

 

[05TurboWagon]

I don't seem to be having any more leaks or air in the form of drips or air intrusion into the lines. The leak around the fuel cooler seems to have stopped as well (I think this is due to replacing other lines in the engine compartment). This weekend, I am still going to pull it off and do a pressure test on both the cooler and the lines.

It seems like am still having cold start issues. At first, I thought I was still getting air intrusion. I let the wagon sit for about 8 hours over night (got down to 25F); it was probably 32-35 when I tried starting it. Long crank but got it started. I started it up several times between 7:30 - 9am. After the initial long start, she started right up. As a confirmation for air intrusion, I let it sit from 9am until about 7pm (~55-60F). She started right up. This morning, it was another long start (35F). I thought, maybe my battery is going out, even though it was picked up in 2018. I thought maybe it was the battery. It measured 12.2V this morning after sitting for 8+ hours. After work, I had the battery and alternator load tested. Both tested good.

At this point, I am confused and would appreciate some suggestions. I'm going to figure out how to test the cam and crank position sensor. I thought I read somewhere that a bad cam sensor will cause start issues when hot, while a crank sensor will cause issues when cold. I don't want to start throwing money at it until something changes, but I will if I have to. Can anyone suggest any other tests with vagcom that would be helpful? Maybe extended glow plug operation?

I will update when I figure something out as well.

 

[irvingj]

"The tandem pump is on the right side of the engine." Thanks, I see it. I knew that supplied vacuum but didn't realize it did double duty as the HP fuel pump.

Yesterday, after the car had sat for 4 days, it cranked for a number of revolutions, 10-15 seconds on the starter, with no joy, not even a fart. That was worse than usual. (When turning key to ON position, I could hear pump operating in the tank.)

Shut key off, waited a moment, turned back on, waited for GP light, then it started fairly quickly. No further issues all day, occasionally starting "normally" -- after only one or two revolutions.

Is the lift pump the most likely candidate? (All filters, including fuel, were changed @ 150K, a month ago.)

 

[irvingj]

And the same thing today -- car had sat for 2 days, would not fire on first attempt. Shut off key, waited, turned it back on, confirmed "noise" in the rear which I assume is lift pump, and it started up. No other issues throughout the day, with several stops & re-starts. Hmmmm....

 

[JB05]

Is the fuel filter full at all times? If not, then the lift pump could be at fault.

 

[05TurboWagon]

And the same thing today -- car had sat for 2 days, would not fire on first attempt. Shut off key, waited, turned it back on, confirmed "noise" in the rear which I assume is lift pump, and it started up. No other issues throughout the day, with several stops & re-starts. Hmmmm....

Irving, here's a ghetto way of checking to see if the check valve for the lift pump (in-tank) is hokey. I let the car sit for an hour or two, then pulled the source line to the fuel filter. Fuel didn't squirt out so I figured the check valve in the pump was bad. I personally would check for air intrusion. Work your way from the tank forward, through the various components until you loop around to the return at the tank.

I don't seem to be having a fuel issue now... However, the ESP light is killing me. I have to switch the key off, on, off, on, a random number of times to get the light to go away, then the car will start. At first, it was only happening while cold, now it's happening randomly after I shut the vehicle off and try to start it back up. I cleaned up my garage and put my VCDS cable somewhere I wouldn't lose it... now... yeah. With a bluetooth dongle and scanner, the only error I'm getting is for the O2 sensor, which I don't really care about at the moment. As far as I know, it has nothing to do with fuel trim on the BEW. Someone please correct me if I'm wrong.

 

[irvingj]

I like the idea of adding an additional check valve in the fuel line at the filter, as outlined in a thread referenced in the OTHER "long-crank" thread. Yesterday, after the car having sat for several days, it started "normally" -- a few extra cranks, but not too bad; didn't need to turn key off and repeat seat procedure. ?? If it happens again, I'll try the overnight fuel line clamp-off to try to determine if that's the issue.

"ESP light"? What's that? Don't know that I've ever seen it.

 

[05TurboWagon]

If you look at my video at the top of this chain, it shows the Electronic Stability Program (ESP) light is lit up often when I key on (before starting). If the light is on, I'm guaranteed that the car will not start. If I turn the key off and on, at some point it goes away and I can start the car. I'm still trying to figure out what all can affect the ESP light. Erroring on the side of caution, I just bought a new battery from NAPA. NAPA The Legend Premium AGM Battery BCI No. 94R 800 A Glass Mat. Hopefully this will have more than enough power to start the bugger during those really cold says, after I figure out what is going with the rest of Christine.

 

[pedroYUL]

Have you checked your glow plugs and harness?

 

[05TurboWagon]

Have you checked your glow plugs and harness?

I have not tested the harness, but recently replaced the glow plugs a year ago. I did check them for continuity and resistance just to rule them out. My issues happens if the engine is cold or at full op temp, but is significantly worse when cold.

 

[pedroYUL]

Probably worth changing that GP harness if it is still the original one. Luckily, supply of these is plentiful and the job of splicing a new one is not bad at all.

Maybe clean/adjust injector harness?
Maybe check for torsion angle, did you replace the timing belt recently?

Extremely retarded timing will make your engine very hard to start, and then it will complain quite a bit until it warms up and timing advances a little.

 

[05TurboWagon]

Probably worth changing that GP harness if it is still the original one. Luckily, supply of these is plentiful and the job of splicing a new one is not bad at all.

Maybe clean/adjust injector harness?
Maybe check for torsion angle, did you replace the timing belt recently?

Extremely retarded timing will make your engine very hard to start, and then it will complain quite a bit until it warms up and timing advances a little.

The timing belt was replaced shortly before I picked up the care in August of 2019. I have put 11K miles on it since then. So, about 16K total on the new timing belt.

I am typically very good at recognizing patterns. However, you said something about the glow plugs which got my attention this morning. I noticed that, whenever the ESP light comes on, the glow plug light does not. After a few on/off cycles, the glow plug light pops on AND the lift pump engages. I also found my HEX-V2 adapter for VCDS... I apparently put it back in the box, and sat it in a clearly visible location (since I knew I was going to need it) while cleaning up the garage. That explains why I couldn't find it. I am going to go out and run a full scan in a few minutes to see what I can find. I have not checked the torsion angle, nor do I know how to do so, but will educate myself on it shortly. I am still learning the ins and outs of VCDS.

 

[05TurboWagon]

So, after finally finding my HEX-V2 I ran an autoscan, results are as follows:

Tuesday,12,January,2021,16:45:35:48492
VCDS -- Windows Based VAG/VAS Emulator Running on Windows 8 x64
VCDS Version: 20.12.0.1 (x64)  HEX-V2 CB: 0.4529.4
Data version: 20201125 DS322.1
www.Ross-Tech.com


VIN: WVWSR61J65W063424   License Plate:


Chassis Type: 1J (1J - VW Golf/Bora IV (1998 > 2006))
Scan: 01 02 03 08 15 16 17 19 22 29 35 36 37 39 46 47 55 56 57 75
          76
 
VIN: WVWSR61J65W063424   Mileage: 539530km-335248miles
-------------------------------------------------------------------------------
Address 01: Engine        Labels: 038-906-016-BEW.lbl
   Part No SW: 038 997 016 H    HW: 028 101 181 2
   Component: R4 1,9L EDC G000SG  9970 
   Revision: 12345678    Serial number: VWZ7Z0D0917977
   Coding: 0150031
   Shop #: WSC 23329 444 83999
   VCID: 2313EF0617CE2ED34E0-5184

1 Fault Found:
17524 - Oxygen (Lambda) Sensor Heating; B1 S1
            P1116 - 000 - Open Circuit
             Freeze Frame:
                    RPM: 882 /min
                    Torque: 32.0 Nm
                    Speed: 0.0 km/h
                    Load: 0.0 %
                    Mass Air / Rev.: 290.0 mg/str
                    (no units): 0.20
                    (no units): 0.0
                    Bin. Bits: 11001001

Readiness: 1 1 0 0 0

-------------------------------------------------------------------------------
Address 03: ABS Brakes        Labels: 1C0-907-37x-ESP-F.lbl
   Part No: 1C0 907 379 M
   Component: ESP FRONT MK60      0102 
   Coding: 0019458
   Shop #: WSC 01266 785 00200
   VCID: 34311C5AA220B96BA7A-5184

2 Faults Found:
01314 - Engine Control Module
            013 - Check DTC Memory - Intermittent
01314 - Engine Control Module
            004 - No Signal/Communication - Intermittent

-------------------------------------------------------------------------------
Address 15: Airbags        Labels: 6Q0-909-605-VW5.lbl
   Part No: 1C0 909 605 F
   Component: 17 AIRBAG VW61 0108 0003 
   Coding: 12599
   Shop #: WSC 01266 
   VCID: 270BFB1666F6C2F3128-513C

No fault code found.

-------------------------------------------------------------------------------
Address 16: Steering wheel        Labels: 1J0-907-487-A.lbl
   Part No: 1J0 907 487 A
   Component: Lenkradelektronik   0005 
   Coding: 00118
   Shop #: WSC 01266 
   VCID: 2F3B13364E069AB3DA8-5184

No fault code found.

-------------------------------------------------------------------------------
Address 17: Instruments        Labels: 1J0-920-xx5-17.lbl
   Part No: 1J5 920 906 Q
   Component: KOMBI+WEGFAHRSP VDO V06 
   Coding: 15232
   Shop #: WSC 00000 
   VCID: 3B2337668A7E7613660-513C
   WVWSR61J65W063424     VWZ7Z0D0917977

2 Faults Found:
01314 - Engine Control Module
            49-10 - No Communications - Intermittent
01304 - Radio
            49-00 - No Communications

-------------------------------------------------------------------------------
Address 19: CAN Gateway        Labels: 6N0-909-901-19.lbl
   Part No: 6N0 909 901
   Component: Gateway K<->CAN    0001 
   Coding: 00006
   Shop #: WSC 01266 
   VCID: 70B9D04A93B8C54B832-513C

2 Faults Found:
01314 - Engine Control Module
            49-10 - No Communications - Intermittent
01304 - Radio
            49-00 - No Communications

-------------------------------------------------------------------------------
Address 46: Central Conv.        Labels: 1C0-959-799.lbl
   Part No: 1C0 959 799 C
   Component: 8A Komfortgerát HLO 0004 
   Coding: 00258
   Shop #: WSC 01266 
   VCID: 372B2B56B6565273828-4B1E

   Subsystem 1 - Part No: 1C1959801A
   Component: 8A Tõrsteuer.FS KLO 0202 

   Subsystem 2 - Part No: 1C1959802A
   Component: 8A Tõrsteuer.BF KLO 0202 

   Subsystem 3 - Part No: 1C0959811A
   Component: 8A Tõrsteuer.HL KLO 0202 

   Subsystem 4 - Part No: 1C0959812A
   Component: 8A Tõrsteuer.HR KLO 0202 

4 Faults Found:
00912 - Window Regulator Switch; Front Left (E40)
            27-10 - Implausible Signal - Intermittent
00929 - Locking Module for Central Locking; Front Passenger Side (F221)
            27-10 - Implausible Signal - Intermittent
00930 - Locking Module for Central Locking; Rear Left (F222)
            27-00 - Implausible Signal
00931 - Locking Module for Central Locking; Rear Right (F223)
            27-00 - Implausible Signal

End----(Elapsed Time: 04:58, VBatt start/end: 12.0V/12.0V. VIgn 11.9V)-----

Addressing issues, top down:
Address 01: Engine
Component: R4 1,9L EDC G000SG 9970
17524 - Oxygen (Lambda) Sensor Heating; B1 S1
P1116 - 000 - Open Circuit

I know the o2 Sensor is borked. I have a replacement, I'm just lazy and haven't done it... plus it's cold. Unless this will affect fuel trim and mileage, I don't much care.

Address 03: ABS Brakes
Component: ESP FRONT MK60 0102
01314 - Engine Control Module
013 - Check DTC Memory - Intermittent
01314 - Engine Control Module
004 - No Signal/Communication - Intermittent

I assume this is the ABS sensor for the passenger side - front?
While I was sick, I paid another guy to replace my turbo when it crapped out in Sept 2019 (never realized it threw a DTC, but didn't have VCDS at the time)

Address 17: Instruments
Component: KOMBI+WEGFAHRSP VDO V06
2 Faults Found:
01314 - Engine Control Module
49-10 - No Communications - Intermittent
01304 - Radio
49-00 - No Communications

I assume this is the dashboard tach? It does not register RPM until after the car starts. Afterwards, the gauge registers, as well as RPM reading on Torque Pro.

Address 19: CAN Gateway
Component: Gateway K<->CAN 0001
2 Faults Found:
01314 - Engine Control Module
49-10 - No Communications - Intermittent
01304 - Radio
49-00 - No Communications

I assume this is because I replaced the monsoon stereo with a Kenwood Excelon DDX9906XR with a PAC's RP4-VW11 to retain steering wheel controls. Does it matter much or do I need to get an interface to play nice with the canbus?

Address 46: Central Conv.
Component: 8A Komfortgerát HLO 0004

Subsystem 1 - Part No: 1C1959801A
Component: 8A Tõrsteuer.FS KLO 0202
Subsystem 2 - Part No: 1C1959802A
Component: 8A Tõrsteuer.BF KLO 0202
Subsystem 3 - Part No: 1C0959811A
Component: 8A Tõrsteuer.HL KLO 0202
Subsystem 4 - Part No: 1C0959812A
Component: 8A Tõrsteuer.HR KLO 0202

4 Faults Found:
00912 - Window Regulator Switch; Front Left (E40)
27-10 - Implausible Signal - Intermittent
00929 - Locking Module for Central Locking; Front Passenger Side (F221)
27-10 - Implausible Signal - Intermittent
00930 - Locking Module for Central Locking; Rear Left (F222)
27-00 - Implausible Signal
00931 - Locking Module for Central Locking; Rear Right (F223)
27-00 - Implausible Signal

The only thing that makes sense here is the rear left and right. The rear left lock goes up most of the time, but has issues going back down. The rear right goes up and down most of the time but gets stuck. I can only assume that the mechanism are dirty/unlubricated or they are dying.

It seems like the ABS sensor or possibly the tach would cause the ESP light to trigger on key on? I can also understand why, if the issue is actually the crank sensor, as to why there would be a failure to start.

However, what I do not understand is that, if the comms w/ the ECM were intermittent, why key on/off would "fix" this issue and allow the car to start. Furthermore, to see if the DTC's would pop back up, I cleared the all of them. When I did that, turned off the car, and disconnected vagcom/cable, I tried starting the car and it started IMMMEDIATELY like a damn champ. I took her for a spirited test drive; after I came home, I ran another scan... nothing but the o2 Sensor popped. Once she is good and icy cold, I am going to go start her up again and see what I can see, then take a VERY spirited test drive and scan again.

As far as the locks, do you think it would be worth while to take the rear doors apart and clean/lube the locking mechanisms, or simply replace them? I'm not sure what the deal was with the passenger-front locking mechanism nor the front left window regulator switch... both work like butter.

What am I missing? Could stored DTC's cause issues? If there are issues with the RPM gauge/crank sensor or abs sensor, would clearing the codes fix my issue, possibly to have them pop up later? Is there a way to test the ECM for failure status? I looked at my wiring, I don't think that is an issue. Could it be a ground I have since fixed? I'm currently more enlightened, but very much at a loss.