New to TDI's, chasing an oil leak

Stuffing

Active member
Joined
Dec 13, 2017
Location
Seattle
TDI
2003 Golf TDI ALH
New to TDI's, engine dead from brief runaway?

EDIT 2: Latest status on runaway engine:
Cranks just fine.

Turbo still leaking oil into intake.

Engine is timed near-perfectly. (Pics on my latest post with pictures)

(Cold) Compression test shows lower compression in cylinder 2, though barely within spec. Numbers are all ~400+psi

Cam and lifters do not have any obvious damage, and look fine to me.

I'm trying to decide if there is anything left to check before I bolt on a new/rebuilt turbo with a cleaned out intake.




EDIT: Go to latest post for current status, tl;dr is my engine ranaway briefly, presumably because the turbo was leaking large quantities of oil. Now trying to determine if the engine was killed in the process.


Hi everyone,
This is my first TDI and first VW. I have a little bit of mechanical experience but nothing specifically related to diesels and turbos, so go ahead and assume I'm a dummy.

I have a 2003 TDI with 175k miles that I bought recently. So far I've fixed or replaced:

  • starter motor (good solenoid, bad motor)
  • thermostat that was stuck open
  • start of injection timing that was throwing a code (dead on now, no more engine codes)
  • drained intercooler (never been done I'm assuming, drained 1/2 quart)
  • new oil, filter etc

I'm losing oil quickly enough that it's a little concerning. For a loose estimate, I'd say I'll probably go through nearly a quart of oil for top-ups until my next change. If we assume the intercooler's never been drained I don't think what came out is enough to account for what's missing, but I can check on it later for more leakage.

I've been looking around for leak spots but I haven't seen much. I do keep seeing oil on top of the valve cover after I clean it off and drive:


The area under the vacuum pump looks a little dirty too:


I also noticed that the dust cover for the belt tensioner shock has dissolved off and is loose, and there's some oil there too (from the tensioner? new one is incoming either way):


It's also dirty behind the EGR, forgot to snap a pic.

I'm making this post since I'm new to this engine and don't know where to start looking for leaks. I'm hoping the turbo's not bad but this engine is pretty old. I can't say for sure if I'm missing out on power because I have no frame of reference for this powerplant... It's by no means fast, but then it's not really supposed to be. I currently get 30mpg if I drive in the city only (hilly Seattle...) and about 40mpg highway.

I'd appreciate any advice you all can give, thanks!
 
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mrfiat

Veteran Member
Joined
Mar 24, 2008
Location
Los Ranchos, NM
TDI
2003 Jetta TDI (Reflex Silver) , 2003 Jetta TDI Wagon (Black)
Hi. What did you do get get rid of the CEL code? (start of injection timing)

Were you getting this code: "17656 - Start of Injection Timing Regulation: Control Deviation"

I do go through a bit of oil in my 2003 also. I think it is from my turbo seals. I have fixed all other leaks. You might want to spray your engine with a can of engine cleaner and then see where the leaks are.

I'm in Albuquerque, but do go to Seattle quite a bit.
 

Stuffing

Active member
Joined
Dec 13, 2017
Location
Seattle
TDI
2003 Golf TDI ALH
Hi. What did you do get get rid of the CEL code? (start of injection timing)

Were you getting this code: "17656 - Start of Injection Timing Regulation: Control Deviation"

I do go through a bit of oil in my 2003 also. I think it is from my turbo seals. I have fixed all other leaks. You might want to spray your engine with a can of engine cleaner and then see where the leaks are.

I'm in Albuquerque, but do go to Seattle quite a bit.
Yup! I had the exact same code. I was lucky and my car came with the VAGCOM adapter. I followed the procedure shown in the video here: http://wiki.ross-tech.com/wiki/index.php/17656/P1248/004680

If you don't have that tool yet, I highly recommend getting it as I imagine there are a lot of other issues it can help solve.

When turbo seals start to fail and bleed oil, does that also tend to come with a performance hit? As I said, I don't really have a frame of reference of this engine's power but I imagine MPGs would begin to suffer as well were that the case.

Per your suggestion I'll do a deeper engine clean when I can, that should help me out.
 

mrfiat

Veteran Member
Joined
Mar 24, 2008
Location
Los Ranchos, NM
TDI
2003 Jetta TDI (Reflex Silver) , 2003 Jetta TDI Wagon (Black)
I have the Vagcom thx. I have two friends with that exact same error. We have already set their injection pump correctly (like you did) and that did not correct the error code. If you did anything else to correct it , please let me know.

I don't think there is a performance hit if the seals are leaking. It just wastes oil and could cause a runaway. I have already cleaned out my intercooler, so no worries there.
 

oilhammer

Certified Volkswagen Nut & Vendor
Joined
Dec 11, 2001
Location
outside St Louis, MO
TDI
There are just too many to list....
Couple things:

If the timing was far enough out to set that DTC, and retiming the pump corrected it, then the timing belt was almost certainly installed wrong. The engine still runs, so it may not have been installed THAT wrong, but I would still be questioning the whole job.

Using a quart of oil every 10k miles is not something I'd be too concerned with. Some ALHs use more oil than others, but I would say that is well within the tolerance of the engine.

Some oil residue in the charge air tract is 100% normal, and so long as the car gets driven spirited once in a while (the more the better), there will never be any accumulation to worry about. Even a little oil passed by the turbo is not cause for concern.

It is common for some oil seepage around the valve cover and vacuum pump. You can try and reseal them if you like, just don't get discouraged if some remains. The valve cover's gasket is integral, so bad leaks will require a new cover. However, I have had good success with Permatex aviation sealant, especially at the corners of the cam caps, at curbing that seepage. The vacuum pump has a replaceable seal, but in some cases the pump itself is leaking.

The belt tensioner shock absorber can leak some of its juice too, and eventually will need to be replaced. So long as your alternator one way pulley is not locked up, and the tensioner is not bouncing, you should be OK.
 

Mike_04GolfTDI

Top Post Dawg
Joined
Nov 19, 2003
Location
Richmond, BC, Canada
TDI
Mine: 2019 Golf R DSG, Wife's: 2015 Golf Comfortline TDI
^ My car has used a quart of oil every 10,000 miles since new. (I bought the car new)

So at the 5000 mile mark I top it up with half a quart. Then at 10,000 it's time to change the oil anyway.
 

IndigoBlueWagon

TDIClub Enthusiast, Principal IDParts, Vendor , w/
Joined
Aug 16, 2004
Location
South of Boston
TDI
'97 Passat, '99.5 Golf, '02 Jetta Wagon, '15 GSW
If the car has a manual transmission that FE isn't great. I almost never see less than 40 MPG under any conditions. Timing set up wrong can negatively affect FE, but I also wonder if your turbo is boosting properly. A half-quart of of out of the intercooler is significant, and may indicate low boost. If you have access to VCDS you should run a boost log.
 

UhOh

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Dec 24, 2014
Location
PNW
TDI
2000 & 2003 Golf GLS (2005 Mercedes E320 CDI)
BIG sigh of relied that the OP had the presence of mind to drain the IC first thing!

Oil accumulation and how much oil is being pushed through the intake system will differ. With good boost you'll accumulate little oil (as long as the turbo isn't really bad) as it'll be sent to the engine to be burned.

My spare car seems to be going through about 1/2 qt every 3k miles. Recent acquisition and now has about 217k miles on it. Turbo was checked and seemed good. Might be oil rings or valve guides/valve seals, dunno. (maybe one day I'll bother to get to the bottom of it)
 

Stuffing

Active member
Joined
Dec 13, 2017
Location
Seattle
TDI
2003 Golf TDI ALH
Hey guys, back again to address a couple things.

If the timing was far enough out to set that DTC, and retiming the pump corrected it, then the timing belt was almost certainly installed wrong. The engine still runs, so it may not have been installed THAT wrong, but I would still be questioning the whole job.
You could be right, although the PO also replaced the pump a couple years after the last timing belt job (10-20,000 miles later), so I'm guessing that the timing may have been off because of that. The reason why they didn't see something wrong might have been because the car didn't throw the timing code until it reached operating temperature, which could never happen until it sat in heavy traffic for a long time. Maybe the pump and cam are both off... Can this be checked with VCDS? I suppose a timing light isn't going to work here, huh :rolleyes:

If the car has a manual transmission that FE isn't great. I almost never see less than 40 MPG under any conditions. Timing set up wrong can negatively affect FE, but I also wonder if your turbo is boosting properly. A half-quart of of out of the intercooler is significant, and may indicate low boost. If you have access to VCDS you should run a boost log.
I've got VCDS, I'll run a boost log and see what's up. Will an expert need to see that log or is it understandable enough for me to just compare it to a good log?

BIG sigh of relied that the OP had the presence of mind to drain the IC first thing!
Yeah, I'm glad I did a little research before DIYing :eek: You never know what kind of fun quirks a car might have in regards to maintenance...

Also, I'm pretty sure my alternator pulley clutch is bad, which is why the tensioner isn't doing so well. That's getting changed ASAP.
 

BobnOH

not-a-mechanic
Joined
May 29, 2004
Location
central Ohio
TDI
New Beetle 2003 manual
..................You could be right,,,,,,,,,,,,,,,,,,,,,,
Oilhammer is almost always right. You want check mechanical timing. You put the crankshaft at TDC, align the cam (we lock when servicing belt) with #1 camshaft lobes straight up and align the hole in the IP pulley with the hole in the IP. Please see Timing Belt change instructions for more detail. Then it's VCDS time to fine tune.
 

Stuffing

Active member
Joined
Dec 13, 2017
Location
Seattle
TDI
2003 Golf TDI ALH
Yikes. What a crappy day...


So I finally got around to doing my boost log, and during my 3rd gear pull around 3300rpm the engine ran away. I got it turned off within 3-5 seconds and pulled over safely, and the car remains there. I haven't tried starting it again, I didn't want to make things worse.


I'm currently weighing my options right now for what to do next. The runaway was extremely brief, though it reached probably almost 6000rpm, highest shown on the boost log was around 5500rpm (Yes, I have a boost log of my engine during the runaway if anyone's curious). Is it worth trying to fix? I'm guessing the turbo oil seals must have failed, since the intercooler was just drained...



Will a simple compression check + visual inspection of head and cam be enough for me to figure out if the engine is badly damaged? Or do I need a shop to take a closer look?
 

Stuffing

Active member
Joined
Dec 13, 2017
Location
Seattle
TDI
2003 Golf TDI ALH
I ran two compression tests, second time after I charged the battery for a bit (though I got lower numbers?). Keep in mind the engine was totally cold since I didn't want to run it.



Run 1:
Cylinder 1: 455psi
Cylinder 2: 439psi
Cylinder 3: 470psi
Cylinder 4: 510psi

Run 2:
Cylinder 1: 450psi
Cylinder 2: 395psi :eek:

Cylinder 3: 448psi
Cylinder 4: 500psi



I'm assuming these numbers are bad because of cylinder 2... Is it too much to hope for that oilhammer was right and the timing was off? Could that throw the compression numbers off too? I'd like to think that since everything sounded fine when cranking at least.



Oh, another thing to note, there was a bit oil oil mist spraying out of each cylinder (I think more so from #2) when I cranked without the glow plugs in.
 

BobnOH

not-a-mechanic
Joined
May 29, 2004
Location
central Ohio
TDI
New Beetle 2003 manual
........................off? Could that throw the compression numbers off too? I'd like to think that since everything sounded fine when cranking at least.



Oh, another thing to note, there was a bit oil oil mist spraying out of each cylinder (I think more so from #2) when I cranked without the glow plugs in.
No, don't see how the timing would affect compression.
Oil mist? Out the injectors? Clear that up, can only help things.
When you get back to it, hook up a battery charger and run the compression check multiple times until you get consistent numbers.
Side note- If the injectors don't seal and you're checking compression at the glow plug hole, that could affect compression.
 

Stuffing

Active member
Joined
Dec 13, 2017
Location
Seattle
TDI
2003 Golf TDI ALH
No, don't see how the timing would affect compression.
Oil mist? Out the injectors? Clear that up, can only help things.
When you get back to it, hook up a battery charger and run the compression check multiple times until you get consistent numbers.
Side note- If the injectors don't seal and you're checking compression at the glow plug hole, that could affect compression.

I could be imagining this wrong, but if timing were slightly retarded (or advanced, might have them mixed up) couldn't the intake valve for a cylinder open just a little too late on the intake stroke and then close a little too late on the compression stroke, causing the cylinder to not bring in as much air and then lose some air if the valve is still open as the piston begins traveling back up? I guess none of that matters if each cylinder is affected equally, since I'm mostly just looking for deltas between them.

I've got the battery hooked up to the charger again today, I'll run the tests again once it's topped up.
What I meant by oil mist is that the cylinders with no glow plugs were blowing out an oily mist from the glow plug holes. The injection pump was disconnected, so no fuel should have been injected. Maybe leftover oil that caused the runaway?

Could a badly sealed injector give me compression numbers bad enough to look like a bent rod/bent valves/damaged piston?
 

BobnOH

not-a-mechanic
Joined
May 29, 2004
Location
central Ohio
TDI
New Beetle 2003 manual
I'd think the timing would have to be pretty far off to affect the compression test.

The gauge does not take a snapshot, but rather responds to the highest compression achieved. Even so, it would be nice to know where it's timed. Put it at TDC, cam slot aligned (#1 lobes up) and see if the pump hole is close.
 

Stuffing

Active member
Joined
Dec 13, 2017
Location
Seattle
TDI
2003 Golf TDI ALH
Ok, another long post with lots of pictures.
Here were my compression numbers from the freshly charged battery:
Cylinder 1: 455
Cylinder 2: 439
Cylinder 3: 470
Cylinder 4: 510
I tried my best to check the timing. Things looked wrong to me. With cylinder 1's cam lobes pointing up in a V, there was a white mark on the flywheel, but no indentation in the metal:
(Sorry about the paper towel messing with the lighting)
Cam Angles:

Flywheel Mark:


I looked hard on the flywheel for anything that looked more like the marks I've seen in timing belt instruction pages, I only found one that I thought was right and this is where the cam lobes were:
Cam Angles:

Flywheel Mark:

Am I reading this right? It looks WAY off to me.
Based on these numbers, is it worthwhile to continue repairs (and maybe correct timing)?
 

wonneber

Top Post Dawg
Joined
Oct 12, 2011
Location
Monroe, NY, USA
TDI
2014 Jetta Sportwagon,2003 Jetta 261K Sold but not forgotten
Am I reading this right? It looks WAY off to me.
Based on these numbers, is it worthwhile to continue repairs (and maybe correct timing)?
That does look like the TDC mark to me.

If you did have valve contact and the compression numbers do indicate it in the 1st comp test then the low compression cylinder(s) are bent.

Even if you did replace the belt it's generally just a matter of time (10K miles or less) for the valve head to break off and then it's much worse.

Did you see any spider web cracks on the top of the lifters?
Scrutinize the ones for cylinder 2.
 

Stuffing

Active member
Joined
Dec 13, 2017
Location
Seattle
TDI
2003 Golf TDI ALH
Before I go further, I want to thank you all for your help with guiding me through this. It's been a real pain but at least it's kind of fun for me.

I gave the cam and lifters a good look, I don't have a trained eye for this so you'll have to bear with me.

The cam looked like it had a little wear, most notably the cam lobes had two straight black-ish lines across them, don't know what that's from.
The lifters looked OK to me, at the very least not caved in or shattered-looking, but I did see what might have been small lines pointing into/out of the center of the circle. Take that with a grain of salt, it might have just been dirty and I might have just been trying to see what you described.

I've got pictures of the cylinder 2 cam lobes + lifters here(warning, they're real big), I left them uncompressed so you can zoom in all you like.
Is it possibly time to pull off the head and inspect the bottom end for damage?
 

KyleMillione

Veteran Member
Joined
Jan 27, 2017
Location
Yaphank, New York
TDI
02 Jetta, 03 Jetta
I can’t tell from the photos If the cam lobes are both pointed down on the original timing mark. If so the crank is 180 deg out, that happened to me on a tb job before. Idk if the factory messed up or the po. Shouldn’t cause any damage, if you redo the belt you should align it to the factory marks. If you want to check it, remove the glow plug on cyl 1 and see if the piston is at tdc when the cam is facing directly 2 lobes up on cyl 1. Just be careful when you feel for the piston, it has a cup and stuff will get jammed if you leave it in there and rotate. I also don’t know if certain smf flywheels have a timing mark in the wrong spot, because theoretically they’re in the wrong car (gurus chime in here). If I was in your situation, this is how I’d proceed.
 
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Stuffing

Active member
Joined
Dec 13, 2017
Location
Seattle
TDI
2003 Golf TDI ALH
Hey guys! I'm back again with hopefully some good news.
From KyleMillione's suggestion, I checked timing again, this time with a coat hanger in the #1 glow plug hole to check for the piston's maximum height. I must have missed the right mark the first time. Here's what I saw:

Now that 100% looks like the correct flywheel TDC mark to me, the other mark I saw must have been something else. With the flywheel in this location, here's the #1 cam lobes:


That looks MUCH better to me.
I'm almost 100% ready to just go ahead and replace my leaky turbo and get the intake cleaned out. Only thing I'm worried about is that lower compression on #2 being just BARELY in spec. It seems like the engine might be safe to idle as long as I drain any more intake oil out.
Would it be worthwhile to do another compression test at operating temperature and see if it corrects?
 
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