Where to stop?

Fix_Until_Broke

Top Post Dawg
Joined
Aug 8, 2004
Location
Menomonee Falls, Wisconsin, USA
TDI
03 Jetta, 03 TT TDI
It's a steady white haze at idle when cold - If you hold it at 2000 rpm no load and it's still (no breeze) it will bellow white smoke and it smells like an old non turbo diesel from the 60's

I adjusted the timing up to "a little" above the green line - I forgot to wait for the glow plugs this morning so it started poorly again (Bad habit from the last 8 years - if it's above freezing, I used to be able to just get in and turn the key and it would fire right off).

We'll see how Monday morning goes to start the car.

It was shaking/vibrating/rattling pretty loud tonight after getting home from the 250 mile road trip. I hope it's not coming apart again...
 

ArturCosta

Veteran Member
Joined
Dec 8, 2003
Location
Portugal
TDI
Audi A4 Avant 1996 Silver
Agree with everyone else, green line or even slightly above for the timing graph.

With NoJoke's wagon, Mike had to modify the timing maps like crazy because of the very low CR. The motor absolutely does not like to be retarded past 3* BTDC. The factory maps have areas where the timing advance goes to minimum possible under low throttle, light load conditions. By keeping the timing 3* or higher at all times on the map, it quit smoking blue/white under light throttle/light load conditions.
In my case I only needed to have SOI never start ATDC... with 0º still doesnt smoke but with -1º it starts to smoke.
Some parts of stock map ask for more then -2,5º and that is where you will smoke more.
If you cant solve this with remap , advancing the timing in the pump or in vag com should do the work ;)
 

Fix_Until_Broke

Top Post Dawg
Joined
Aug 8, 2004
Location
Menomonee Falls, Wisconsin, USA
TDI
03 Jetta, 03 TT TDI
Not really - I'm pretty frustrated with it.

I played around with cam timing this weekend - it generally starts better when cold and has a little better tip in response (less soft in the lower RPM's) with advanced cam timing.

I also pop tested the injectors and didn't really find anything wrong, but they didn't look great (spray pattern) either. Still sounds like a cold IDI most of the time and has a steady light haze behind it anything over 40% throttle.

I thought I had the vibration fixed this weekend as well, but after a couple days it's back just as bad as ever.

I'm not sure what to do next - nozzles? injection pump? dynamite? The vibration comes and goes - some days smooth as silk, others like driving a massage chair.
 

TDIJetta99

Top Post Dawg
Joined
May 17, 2005
Location
Port Jervis, New York, USA
TDI
03... Faster than yours =]
put some more miles on it and don't be afraid to run it down the highway at 75mph in 4th... It'll get better as the engine breaks in... Mine was a pile of junk until I started getting p1ssed of at it....
 

Fix_Until_Broke

Top Post Dawg
Joined
Aug 8, 2004
Location
Menomonee Falls, Wisconsin, USA
TDI
03 Jetta, 03 TT TDI
It's got ~3k miles on it. I have not been shy of getting after it, but only a minute at a time at most (climbing a mile long 6% grade) and the occasional blast through the gears. With the IDI sound so loud I was concerned about a streaming injector or something so have not been too hard on it for too long so as not to cause permanent damage.

Maybe I need to go pull a couple thousand pounds around again :) for a few hundred miles. It'll either kill it or cure it I suppose.
 

TDIJetta99

Top Post Dawg
Joined
May 17, 2005
Location
Port Jervis, New York, USA
TDI
03... Faster than yours =]
Ya 3k is nothing.. I put 3k on my car the SECOND time I drove it after the rebuild.. The first test drive was an 80 mile trip at 3500rpm.. Changed the oil and towed my bike trailer to Daytona and back 3 days later.. Didn't see under 2500rpm for the whole trip except when the car was stopped or cold.. The whole attitude of the car changed on the drive to and from Florida.. sounded completely different on the return trip and the softness was starting to go away.. I have about 10k on it now and it's really snappy.. It has nothing under 2000rpm due to the pistons and cam, but it's fine otherwise.. I broke the big block in at the dragstrip 12 years ago and it hasn't skipped a beat..

Pull 1500lbs at 3000rpm for a few hundred miles.. That should help clear it up. Better yet, do it towing a car with a dolly. Don't load it up heavily at low rpm though..

I'd make sure the injectors aren't streaming before you do that though..
 

Galactic_Warrior

Veteran Member
Joined
Feb 14, 2002
Location
Milwaukee, WI
TDI
02 Jetta
Just a thought here based on the following assumptions (making sure I understand in my old age):
  • You are running in MAP mode NOT MAF mode.
  • You have ported the head and manifolds (nice work BTW)
  • The EGT's are high.
  • The car smokes more both running and start up (is start up white smoke?)
  • The car sat several weeks from teardown to first fire.
  • The replaement injectors were used, condition unknown.
  • Changing injectors did not have a major benefit.
Assuming your cam and injector timing are correct, then....

You should have more air in the cylinder at the same boost pressure.
But, you are smoking and have high EGT's due to over fueling
You are also smoking on start -up

These all point me to the mechanical behavior of the injectors. Considering that the car sat a while is is possible that the injectors are gunked up (that's a technical term). I recall a while back, a member had his engine down for a while and upon restart, it ran like crap and was loud until he had his injectors serviced.

Think of it like this...They are gunked up and the point of injection is delayed (relative to crank rotation), the spray pattern is poor and fuel may still be injected late in the combustion cycle. All of these lead to late (actual not via the ECU) combusiton initiation and poor atomization leading to high in-cylinder soot and with partially burned fuel. in the exhaust ports and exh manifold. BTW, how does the exhaust smell...bad???

My recommendation is that before you change too many other variables, have Frank or DBW (or even Huckstorf) service your injectors. I don't care how much Diesel Purge or Power Service you use (both good products), that you wil not get them clean enough.

White smoke on start up is incomplete combustion from either a leaking injector or poor timing (injection or cam).

On a relatd note, if your cam timing is advanced, you could also have high EGT' and soot.

Just a few thoughts and observations. Feel free to comment/ critique/ offer constructive comment.
 

eddie_1

Veteran Member
Joined
Dec 27, 2004
Location
Hannover, Germany formerly Toronto & NY
TDI
Jetta Wagon 2003 TDI tuned to 170HP, A6 Wagon 2008 TDI 2.7L tuned to 340HP
This porting business is like a hit or miss affair it seems to me. I am sure when VAG created the engines they use Finite Elements to understand the chamber profile for optimal detonation across rpm etc. It seems like there is no set recipe or known recipe for carving out the head. It is a free style activity bringing varying results. Of course I have no idea how important or unimportant this is, but it seems odd that each car is behaving differently after head porting. I remember seeing even strange dyno graphs after head porting.
 

Ski in NC

Top Post Dawg
Joined
Jul 7, 2008
Location
Wilmington, NC USA
TDI
2001 Jetta ALH 5sp stock
If that was my car, the first thing I would do was try another set of known good injectors.

Strange combustion noise points to crappy spray pattern.
 

Fix_Until_Broke

Top Post Dawg
Joined
Aug 8, 2004
Location
Menomonee Falls, Wisconsin, USA
TDI
03 Jetta, 03 TT TDI
Galactic Warrior

Most of your assumptions are correct

The head has significant porting on the exhaust side, and very little porting on the intake side. The valves have been sunk down to ~0.010" vs ~0.040" stock as well as unshrouding the seat area due to the deeper valve location. Intake and exhaust manifold ports have been matched as deep as physically possible.

Injection timing according to VagCom is correct. Cam timing has been run at 0 degrees and also at 8 degrees advanced. EGT's went up a "little" at steady state and rise faster with advanced cam timing. The engine is a "little" more responsive down in the 1500 RPM range as well.

My PP502's were last run 12Dec2011 and re-started 03March2012 - they were removed from the head and put in a clean, but open to atmosphere, plastic container in the front passenger seat foot well.

A couple weekends ago, I took the PP502's off their bodies and gave them a good cleaning with carb cleaner and pop tested them - again with mixed results. I had a couple injectors that were good, sprayed OK, no leakage/streaming, etc but there were a couple that would pop good a few times and then stream once, then be good again, etc. One thing that I noticed was that it was very difficult to get the needles out of the bodies of the nozzles. Once out and cleaned with carb cleaner they were smooth and free moving, but were really sticky to get out the first time. After all this, the car didn't run any different.

I purchased a used set of stock ALH injectors and installed them with mixed results (see post 316). I don't know how long the stock ALH injectors were out of service before I put them in.

I took the spare set of ALH injectors and put Bosio Race 520's on them and put them in the car tonight. I started it up warm and only drove it around the block quick so it's too early to tell, but initial impressions are much smoother, much quieter, much more powerful and even in the darkness they managed to make a large black cloud of smoke. I'll know more tomorrow once I get more than .2 miles on them. One thing that I did notice was that the exhaust now smells like a normal TDI instead of the acrid eye burning smell it's had since I got it running back in March.

So - Galactic Warrior - I think you were right. I've changed things before and thought I've had problems taken care of initially, only to have them come back in a few days/weeks, so we'll see how this goes.

I'll evaluate the PP502's that I took out and see if I can find something decidedly wrong with one or more of them.

I have a set of BFI Stage 1 Yellow 65 durometer mounts that I hope to install this weekend. I think the ones I put in brand new back in March are junk already (~3500 miles). It was smooth for the first ~1000 miles and has been like driving a bad massage chair ever since (with random periods of smoothness that come/go with the wind).

If anyone sees a stopping point here, give me a shout so I don't miss it :)
 

JFettig

Vendor
Joined
Aug 18, 2010
Location
Blaine, MN
TDI
B5 Passat, 2010 Jetta
Did you shorten the valves or at least check the travels of the hydraulic lifters when you sunk them in .030 from their original position?
 

Fix_Until_Broke

Top Post Dawg
Joined
Aug 8, 2004
Location
Menomonee Falls, Wisconsin, USA
TDI
03 Jetta, 03 TT TDI
No - I remember reading in the Bentley manual that the wear limit for valve protrusion was something crazy like 1mm (0.040") so essentally flush with the head surface. I'll try and find the page where I did the calcs on that and post the picture.
 

JFettig

Vendor
Joined
Aug 18, 2010
Location
Blaine, MN
TDI
B5 Passat, 2010 Jetta
The reason I ask is because I was playing with my PD lifters and everything for sizing springs and they seemed to sit at their max travel when the cam was set down, as in they wouldn't have to pump up much. From their nominal position to the position they sit with the cam was 2mm. Maybe they go further but when I tried to squeeze them further, they were rather stiff.
 

Galactic_Warrior

Veteran Member
Joined
Feb 14, 2002
Location
Milwaukee, WI
TDI
02 Jetta
A few more thoughts...try a Power Service or Diesel Purge cleaning (straight fro the bottle to the IP) as it can't hurt. I still say a good injectpor service is in order.

Next, what is your boost pressure like compared to before the rebuild? Since you are running MAP versys MAF control, you should be the same and with better ports, better airflow and minimal chance of overfueling.

Finally, I have seen several issues of injector fouling due to heat soak with the ULSD and in GDI engines. The more modern fuels are not as tolerant as they used to be.

Trivia questions of day: Why are cam chains wearing at a higher rate in GDI cars versus regular gas port fuel injection?
 

Fix_Until_Broke

Top Post Dawg
Joined
Aug 8, 2004
Location
Menomonee Falls, Wisconsin, USA
TDI
03 Jetta, 03 TT TDI
I did a direct diesel purge in the injection pump back in March - didn't really do anything.

The R520's are significantly more fuel than the PP502's I was running. ~200F higher EGT's - runs 900-1000F @ 70 MPH (1950 RPM) flat and level. Definately a nice sense of urgency in the lower RPM's with these nozzles as well. The tune has not changed so they're a bit smokey if you get after it more than 50% throttle, however they're significantly more powerful.

The engine is quieter/smoother now, but unfortunately even after ~650 miles, it still has a strong IDI knock over ~15% load. On a nice quiet bit of road, you can gradually increase the load on the engine and it goes from smooth and quiet to (what sounds like) one cylinder gets a knock to it, add a little more load and a 2nd cylinder will chime in, more load yet, and all the cylinders are doing it. Lighten the load and you can hear them drop out the same way. There is still a nice puff of white smoke on cold (70F) startup.

Injectors 1st stage are all within ~100 psi (7 bar) of each other (each measured 3 times in a row to evaluate repeatibility). 2nd stage has been harder to determine - my testing has not delivered repeatable results on the 2nd stage (assuming the injectors are repeatable).

The sound/behavior is so similar between my DBW balanced PP502's, stock ALH injectors and the R520's I've installed, that I'm skeptical that the injectors are all doing the same thing.

Thinking out loud here...what can cause diesel knock? Advanced timing? Anything else?
 

Ski in NC

Top Post Dawg
Joined
Jul 7, 2008
Location
Wilmington, NC USA
TDI
2001 Jetta ALH 5sp stock
You reduced compression ratio a little bit, right? That increases the ignition delay, which increases fuel knock. The tune you are running may have advanced injection timing compared to stock. Add the advance to the lower CR and that may get you fuel knock. Larger injectors also tend to advance timing as the injection event is shorter (less throttling in holes) so SOI is about the same, but injection event is shorter.

The pilot injection might not be igniting.

Maybe get your tuner to retard injection some, especiallly at light load??

Early injection usually causes more nailing (fuel knock) but if timing is far enough off, I suppose late timing could do it to.

Play around with your timing (ecu driven, using adaptation), and see if the noise changes.
 

Fix_Until_Broke

Top Post Dawg
Joined
Aug 8, 2004
Location
Menomonee Falls, Wisconsin, USA
TDI
03 Jetta, 03 TT TDI
Compression ratio is ~18:1 - I agree that lower CR will increase ignition delay as the air is cooler at the point of injection with a lower CR, however I don't understand why that would increase fuel knock? Generally, the lower the CR the softer the engine noise is that I've heard. A 6.2 (IDI) at 22.5:1 has more knock than at 18:1 with the timing set the same. Advancing/retarding the injection timing has a significant effect on knock.

I'll play with the adaptation and see if it changes anything.

My latest theory is that at low loads, the main stage of the injector does not open and everything is nice and quiet, but as the load and fuel delivery increase, the main stage opens and that's what is causing the noise.
 

kooyajerms

grocery getter
Joined
May 5, 2004
Location
Pomona, Southern California
TDI
97 B4V (mine), 11 x5 35d (hers) 04 V10 (that one you want), 2014 Q7 (mom's) 74 Shasta 1400
This is a really simpleton answer Matt, but I thought I'd throw it out there.

Maybe with the changes in injectors, your hard lines are tweaked and the injectors are not seating correctly. So even though you know how to seat them, maybe the lines are off, and have been off, so even though the new injectors have helped, they are still not seating perfectly. You said at idle its fine, but as you put load into it, the sound comes in, maybe like a Subaru WRX (don't know what an idi really sounds like). That's why on mine, we couldn't figure it out because it was releasing the exhaust soot at load, and it took some time to see the soot build up on the head/injector holes. Hoping for a fix for ya.



Maybe you got chinese aftermarket copper washers.


Just kidding.
 

Ski in NC

Top Post Dawg
Joined
Jul 7, 2008
Location
Wilmington, NC USA
TDI
2001 Jetta ALH 5sp stock
Compression ratio is ~18:1 - I agree that lower CR will increase ignition delay as the air is cooler at the point of injection with a lower CR, however I don't understand why that would increase fuel knock? Generally, the lower the CR the softer the engine noise is that I've heard. A 6.2 (IDI) at 22.5:1 has more knock than at 18:1 with the timing set the same. Advancing/retarding the injection timing has a significant effect on knock.

I'll play with the adaptation and see if it changes anything.

My latest theory is that at low loads, the main stage of the injector does not open and everything is nice and quiet, but as the load and fuel delivery increase, the main stage opens and that's what is causing the noise.
Ignition delay and fuel knock are closely related. The fuel starts to spray, and the more that gets in cylinder before ign, the sharper the pressure rise and louder the knock.

Can't really compare to IDI, as that is a completely different beast. They had to use higher cr on idi as there is alot more heat transfer from the process air to the relatively cooler glow chamber walls. IDI won't start with cr in tdi range.

Direct injection engines simply were not used in cars until the tdi came out. Direct injection diesel were simply too loud (fuel knock) for cars. With tdi, pilot injection with ecu control of timing got them sociable enough for cars.

For some reason, with your tune, cr, injectors, whatever, you are getting fuel knock similar to a non-tdi direct injected engine.

Do post an audio clip. Maybe the noise is something else entirely.
 
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Fix_Until_Broke

Top Post Dawg
Joined
Aug 8, 2004
Location
Menomonee Falls, Wisconsin, USA
TDI
03 Jetta, 03 TT TDI
In another thread I mentioned that I changed the dogbone mounts from the brand new ones I put in after the rebuild (just a few thousand miles ago) to the Stage 1 inserts from Black Forest Industries.

Below is a picture of the insert that I removed - again with only a few thousand miles on it.




It took me most of a week to notice, but the IDI sound disappeared. I've yet to put the old dogbone inserts back in to see if it comes back, but it was always there before and I have never heard it since. I'm assuming that the dogbone was sloppy enough that it was touching something and making a noise that sounded exactly like an IDI diesel knock. I figured after owning/driving diesels for the last 15 years and 250k miles I'd be able to tell a chassis vibration from diesel knock, but I guess not :).

So now that that mystery is more/less solved, maybe I can move on to whatever the next thing is...oh yeah - the instability at 1100-1200 RPM, install the new cam, radio antenna, 3rd motor mount, skid plate riv nut repair, VagLogs for tune update for the R520's, Compression measurement repeat at varous cam timings, cylinder pressure measurement, etc...
 

jjordan11

Veteran Member
Joined
Jan 5, 2008
Location
Lehi, UT
TDI
1988 Audi 80 quattro PD130, 1982 Westfalia TDI
That's good you got it figured out (IDI sound), noise, vibration, harshness issues can be buggers to even recognize.
 

Fix_Until_Broke

Top Post Dawg
Joined
Aug 8, 2004
Location
Menomonee Falls, Wisconsin, USA
TDI
03 Jetta, 03 TT TDI
The white smoke on startup is less, but it's warm out - 50-60F.

Below ~50% throttle it's relatively smoke free - hard to see in the daytime, but visible in headlights at night. Over ~50% throttle it starts getting more smokey, can easily see a haze in the daytime. 75% and above it's pretty bad - will completely obscure 2 lanes of traffic with a thick brown/black fog. There's always a little puff on tip in if you lean into it below ~1800 RPM

I have not re-tuned it since the rebuild or the R520's have been installed - I need to get some logs taken so a reasonably accurate tune can be done.

I've been playing with the VNT actuator since installing the R520's - I've seen a significant drop in EMP's since installing them - EMP's ~5 psi below boost with the actuator set to start movement at ~7inHg and no spike on spool up. I've been reducing the actuator preload a half turn at a time which has improved response (and reduced smoke on spool up) without raising steady state EMP's while crusing. I am suprised how much the R520's changed the spool of the turbo compared to the PP502's
 

JFettig

Vendor
Joined
Aug 18, 2010
Location
Blaine, MN
TDI
B5 Passat, 2010 Jetta
If you are running a vwmikel tune, he could probably easily adjust the fuel to reduce smoke pretty quick if you have a loader.
 

Fix_Until_Broke

Top Post Dawg
Joined
Aug 8, 2004
Location
Menomonee Falls, Wisconsin, USA
TDI
03 Jetta, 03 TT TDI
I'm currently running a TDTuning (vwmikel) tune and have a loader - I just need to get off my duff and send him some logs.

I guess I could try my RC5 or RC6 tunes just to see how they run (MAF based vs MAP based)
 
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