Lug_Nut
TDIClub Enthusiast, Pre-Forum Veteran Member
- Joined
- Jun 20, 1998
- Location
- Sterling, Massachusetts. USA
- TDI
- idi: 1988 Bolens DGT1700H, the other oil burner: 1967 Saab Sonett II two stroke
(Cause has been identified, see post 64)
2002 Jetta starts easily, idles smoothly, but revs only to 1800 and lots of smoke. I'm out of ideas looking for advice on next steps.
I bought a well priced 02 Jetta with the thought of making it a replacement for the B5.5. It needed work but I thought it was well within my abilities.
Here's a link to the prior owner's post on the same problems:
http://forums.tdiclub.com/showthread.php?t=340942
The summary of advice from that thread:
Turbo replaced (not by the poster, but allegedly by the owner from whom HE bought the car), tried with MAF disconnected, vacuum lines replaced, vacuum valves checked, confirmed cat not blocked-up, intake piping all connected, timing checked, intake is clear, vacuum hose routing confirmed, vacuum retention (leak test) confirmed, snow screen clear, anti shudder valve functioning correctly.
last advice to that owner was to check the quantity adjuster, the EGR, ECU, and compression. The owner was intending to swap in a known good pump, but the thread ended there and a car for sale thread was started.
So I bought it, and have gone through much of the same.
Heavy smoke?
Note the size of the ash chunks that came out after the car was trailered home.
Maybe the cam and followers are worn such that the valve timing is off, so I pulled the valve cover. YeOW! Sludge city!
I can't see well enough to examine the cam and followers. I drained the sump and this is the viscosity. note the angle of the pan relative to the plywood flat on the ground.
Buttoned it back up and ran a few quarts of sludge thinner through a new filter to clean things. Cam has slight wear showing at the lobe tips and a slight dish of the followers, but nothing I haven't seen before on other engines that run well. The oil flush didn't change the symptoms though.
All four injectors were swapped out for a spare set, no different. VCDS shows the injector balance is +-.5 (+-2.0 is limit)
Down pipe removed (eliminating a blocked cat / exhaust as a cause), no different.
Intake piping removed at anti shudder valve, no boost, but also eliminated the intake /intercooler restriction question, no different.
Pulled the head. Cross hatching is still visible on the walls and only a very slight ridge at the cylinder top. Valve seats look good. New head gasket, bolts, water pump, 100k belt kit, serp tensioner installed, no different. Still starts easily, idles smoothly, but can't exceed 1800 rpm even at no load and copious amounts of grey smoke. Compression is a bit low, but for 250k miles it isn't bad at 330, 345, 345, 330. Timing is just slightly advanced, QA is about 5.
All appears to be normal, so I get permission to use her Golf as a known parts supply.
ECU from her Golf (RC3, EGR delete, immobilizer delete) runs exactly the same in my Jetta as the stock Jetta ECU does, nothing over 1800 rpm is possible. My Jetta ECU runs her engine for a second or two, enough time to get up to 3k+ rpm, before the immobilizer kills operation. Doesn't sound like the ECU.
Swapped in her 11 mm fuel pump, no different.
Swapped in her MAF, no different.
I removed the (allegedly new) turbo as it doesn't spin as freely as I thought it should, possibly from bearing damage due to sludged oil. The vanes look to be in pretty good shape with no play in the bearings, nonetheless I pulled it apart.
Maybe this turbo bearing oil by-pass is the source of the "excess fuel" smoke? A pending run-away? More oil pressure at higher-than-idle rpm pumping more oil into the intake air? Compression causing ignition prior to TDC and holding back the rpm? The turbo needs to be replaced anyway to I blocked off the oil supply for a trial. No different. Same amount of smoke, same limit of 1800 rpm at no load.
VCDS shows no faults.
So I've cleaned and restored full function to the turbo (bearings are still bad and will need to be replaced, but first things first), oil sludge has been cleaned up well enough for now, ECU, injector pump, injectors, MAF have been swapped out with known good substitutes, vacuum hose integrity has been confirmed, solenoid valves operate correctly and properly control vacuum actuators for VNT, EGR and anti-shudder, timing and IQ are within limits. Compression is good enough. The engine starts an idles fine, begins to run raggedly at about 1400 rpm and can't get over 1800~2000 and bellows clouds of smoke.
I'm out of ideas, frustrated, and ready to eat humble pie.
What are your suggestions I try?
2002 Jetta starts easily, idles smoothly, but revs only to 1800 and lots of smoke. I'm out of ideas looking for advice on next steps.
I bought a well priced 02 Jetta with the thought of making it a replacement for the B5.5. It needed work but I thought it was well within my abilities.
Here's a link to the prior owner's post on the same problems:
http://forums.tdiclub.com/showthread.php?t=340942
The summary of advice from that thread:
Turbo replaced (not by the poster, but allegedly by the owner from whom HE bought the car), tried with MAF disconnected, vacuum lines replaced, vacuum valves checked, confirmed cat not blocked-up, intake piping all connected, timing checked, intake is clear, vacuum hose routing confirmed, vacuum retention (leak test) confirmed, snow screen clear, anti shudder valve functioning correctly.
last advice to that owner was to check the quantity adjuster, the EGR, ECU, and compression. The owner was intending to swap in a known good pump, but the thread ended there and a car for sale thread was started.
So I bought it, and have gone through much of the same.
Heavy smoke?
Note the size of the ash chunks that came out after the car was trailered home.
Maybe the cam and followers are worn such that the valve timing is off, so I pulled the valve cover. YeOW! Sludge city!
I can't see well enough to examine the cam and followers. I drained the sump and this is the viscosity. note the angle of the pan relative to the plywood flat on the ground.
Buttoned it back up and ran a few quarts of sludge thinner through a new filter to clean things. Cam has slight wear showing at the lobe tips and a slight dish of the followers, but nothing I haven't seen before on other engines that run well. The oil flush didn't change the symptoms though.
All four injectors were swapped out for a spare set, no different. VCDS shows the injector balance is +-.5 (+-2.0 is limit)
Down pipe removed (eliminating a blocked cat / exhaust as a cause), no different.
Intake piping removed at anti shudder valve, no boost, but also eliminated the intake /intercooler restriction question, no different.
Pulled the head. Cross hatching is still visible on the walls and only a very slight ridge at the cylinder top. Valve seats look good. New head gasket, bolts, water pump, 100k belt kit, serp tensioner installed, no different. Still starts easily, idles smoothly, but can't exceed 1800 rpm even at no load and copious amounts of grey smoke. Compression is a bit low, but for 250k miles it isn't bad at 330, 345, 345, 330. Timing is just slightly advanced, QA is about 5.
All appears to be normal, so I get permission to use her Golf as a known parts supply.
ECU from her Golf (RC3, EGR delete, immobilizer delete) runs exactly the same in my Jetta as the stock Jetta ECU does, nothing over 1800 rpm is possible. My Jetta ECU runs her engine for a second or two, enough time to get up to 3k+ rpm, before the immobilizer kills operation. Doesn't sound like the ECU.
Swapped in her 11 mm fuel pump, no different.
Swapped in her MAF, no different.
I removed the (allegedly new) turbo as it doesn't spin as freely as I thought it should, possibly from bearing damage due to sludged oil. The vanes look to be in pretty good shape with no play in the bearings, nonetheless I pulled it apart.
Maybe this turbo bearing oil by-pass is the source of the "excess fuel" smoke? A pending run-away? More oil pressure at higher-than-idle rpm pumping more oil into the intake air? Compression causing ignition prior to TDC and holding back the rpm? The turbo needs to be replaced anyway to I blocked off the oil supply for a trial. No different. Same amount of smoke, same limit of 1800 rpm at no load.
VCDS shows no faults.
So I've cleaned and restored full function to the turbo (bearings are still bad and will need to be replaced, but first things first), oil sludge has been cleaned up well enough for now, ECU, injector pump, injectors, MAF have been swapped out with known good substitutes, vacuum hose integrity has been confirmed, solenoid valves operate correctly and properly control vacuum actuators for VNT, EGR and anti-shudder, timing and IQ are within limits. Compression is good enough. The engine starts an idles fine, begins to run raggedly at about 1400 rpm and can't get over 1800~2000 and bellows clouds of smoke.
I'm out of ideas, frustrated, and ready to eat humble pie.
What are your suggestions I try?
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