zeitgeist57 Posted November 19, 2012 Report Share Posted November 19, 2012 2000 Passat GLX V6 - 5-speed manual - just turned over 150k miles For the last few weeks, the cold starting has been worse on my Passat than Cleetus. When it sits overnight, starting it up produces a large cloud of blue, wispy smoke, and there is a miss for a few seconds. When it sits for more than a day during the weekend, it will kick and stall once during starting before firing up. For the first time since we've owned it new over 12 years ago, I need to use the gas pedal to get the revvs up at startup. After 10-15 seconds, it idles smoothly and drives very well. It's got various oil leaks - cam seals, VC gaskets (which I recently replaced) - but this smacks to me of valve seals. I'm just surprised at how badly it's deteriorated over a few weeks. Quote Link to comment Share on other sites More sharing options...
Farkas Posted November 19, 2012 Report Share Posted November 19, 2012 Clay, I can't remember if yours is turbo or not. But, what you're describing sounds like valve seals to me. Quote Link to comment Share on other sites More sharing options...
zeitgeist57 Posted November 19, 2012 Author Report Share Posted November 19, 2012 Clay, I can't remember if yours is turbo or not. But, what you're describing sounds like valve seals to me. ATQ 2.8L 30V V6. N/A. Also found in the A4, base A6 from the late '90s-2000s. That's what I'm figuring as well, but with a lot of VAG guys on CR I'd like to see if someone chimes in with the same problem... Quote Link to comment Share on other sites More sharing options...
Patterson Posted November 19, 2012 Report Share Posted November 19, 2012 Valve Seals Quote Link to comment Share on other sites More sharing options...
Aaron Posted November 19, 2012 Report Share Posted November 19, 2012 My guess too. Quote Link to comment Share on other sites More sharing options...
Cordell Posted November 19, 2012 Report Share Posted November 19, 2012 I'd check a couple things like the PCV system for proper operation or oil contamination, but it does sound like valve seals. A couple of the newer GMs are bad about the PCV system sucking oil and causing similar issues. Quote Link to comment Share on other sites More sharing options...
gbracing81 Posted November 19, 2012 Report Share Posted November 19, 2012 Valve seals +/- valve guides Quote Link to comment Share on other sites More sharing options...
ForeverMaker Posted November 19, 2012 Report Share Posted November 19, 2012 What is the cost for a valve seal job? Quote Link to comment Share on other sites More sharing options...
Alfa Turbo Posted November 19, 2012 Report Share Posted November 19, 2012 Blue smoke from burning oil I would not describe as "wispy". Coolant in the combustion chamber will produce a whitish wispy smoke and cause an engine miss until is it cleared out. Has your coolant level been consistent? The head studs are threaded into the Aluminum block and can pull over time allowing coolant (under pressure) to leak into the combustion chamber after sitting a while. As the situation gets worse start ups become more difficult, but generally the engine clears out and runs well after 15-20 seconds. If you are certain it is not coolant related, a clogged PCV could cause the symptoms you are experiencing too. Good luck. Quote Link to comment Share on other sites More sharing options...
6 Speed S4 Posted November 19, 2012 Report Share Posted November 19, 2012 PCV system could be clogged up, but sounds like valve seals to me. Quote Link to comment Share on other sites More sharing options...
zeitgeist57 Posted November 20, 2012 Author Report Share Posted November 20, 2012 Brian, good to hear from you! I see your Alfa around UA...actually, the coolant level drops, but I attribute it to a leak in the secondary coolant pump; it leaves a puddle everywhere it goes. I say wispy, but it's definitely an oil cloud, not a heavy, condensed, SeaFoam-style cloud. I'll research on Passatworld.com to see if anyone's done a valve seal job. I replaced the PCV piping a couple of years ago when I did the clutch job, but I'll research if there is a spot introducing oil back into the engine on the regular now. Thanks, CR! :thumbup: Quote Link to comment Share on other sites More sharing options...
Mr. Jones Posted November 20, 2012 Report Share Posted November 20, 2012 IIRC those have the "pancake" pcv that are notorius for sticking esp when cold. If it was recently disregard of course. Quote Link to comment Share on other sites More sharing options...
slowyota Posted November 26, 2012 Report Share Posted November 26, 2012 ive never seen a case where worn/bad valve seals caused a rough start like that...it would literally take a vwery large amount of oil to make that happen, like more than could ever leak past the seal- deff look into PCV system, also does it rattle at all on cold starts? any CEL's? and as far as valve job, they are pretty expensive since its a 5 valve per cyl setup- the valves are so small that they are usually unable to be "correctly" redone, so replacement is required, though the hillbilly way of lapping may get you by for a while, i would do a compression/leakdown on the motor before you tear it apart..good luck!! Quote Link to comment Share on other sites More sharing options...
slowyota Posted November 26, 2012 Report Share Posted November 26, 2012 The head studs are threaded into the Aluminum block and can pull over time allowing coolant (under pressure) to leak into the combustion chamber after sitting a while. Good luck. the audi 2.8 30v engine is iron block alum head, not saying this situation cannot happen, but much less likely Quote Link to comment Share on other sites More sharing options...
liftedram98 Posted November 26, 2012 Report Share Posted November 26, 2012 ive never seen a case where worn/bad valve seals caused a rough start like that...it would literally take a vwery large amount of oil to make that happen, like more than could ever leak past the seal- deff look into PCV system, also does it rattle at all on cold starts? any CEL's? and as far as valve job, they are pretty expensive since its a 5 valve per cyl setup- the valves are so small that they are usually unable to be "correctly" redone, so replacement is required, though the hillbilly way of lapping may get you by for a while, i would do a compression/leakdown on the motor before you tear it apart..good luck!! I hate you jack :fuuuu::fuuuu::fuuuu::fuuuu: Quote Link to comment Share on other sites More sharing options...
slowyota Posted November 26, 2012 Report Share Posted November 26, 2012 I hate you jack :fuuuu::fuuuu::fuuuu::fuuuu: :fuckyeah: Quote Link to comment Share on other sites More sharing options...
zeitgeist57 Posted November 26, 2012 Author Report Share Posted November 26, 2012 Just got back from Thanksgiving in Georgia...will be leaving for Pittsburgh in the morning for work. Started the Passat just to warm her up and clear out the baffles. It was a good amount of cold cranking to get it running. Blue smoke some moar! No knocks, just missing on a few cylinders until the oil burns away, then smooth again. I'll try to get it over to a shop here soon...just want a second opinion on this and some other wear items... Quote Link to comment Share on other sites More sharing options...
Crossle Posted December 8, 2012 Report Share Posted December 8, 2012 The PCM thought it was -41*C outside. The "whispy" smoke smelled like raw fuel as a result. Of course it's cold enough out now that the exhaust will smoke at start up as a "normal" condition anyway. Quote Link to comment Share on other sites More sharing options...
Trouble Maker Posted December 8, 2012 Report Share Posted December 8, 2012 The PCM thought it was -41*C outside. The "whispy" smoke smelled like raw fuel as a result. Of course it's cold enough out now that the exhaust will smoke at start up as a "normal" condition anyway. So what was the final diagnosis, fix? IAT or some other temp sensor, wiring? Quote Link to comment Share on other sites More sharing options...
Crossle Posted December 8, 2012 Report Share Posted December 8, 2012 G62 ect sensor. Quote Link to comment Share on other sites More sharing options...
Trouble Maker Posted December 9, 2012 Report Share Posted December 9, 2012 What's the logic behind that? If it's been long enough between ignition cycles does it assume external temp=ECT? Then changes cold startup depending on external temp readings? If so, it can't know external temp if it's been a short time between ignition cycles. What does it do in that situation? It seems kind of weird there's no plausibility (compare to another sensor, calculated value) or fail safe check. Why -41C? Just seems like it should have thrown a code... did it but it was a soft code, no lamp was thrown? Just trying to understand the logic/reasoning behind it better. Quote Link to comment Share on other sites More sharing options...
Mr. Jones Posted December 9, 2012 Report Share Posted December 9, 2012 What's the logic behind that? If it's been long enough between ignition cycles does it assume external temp=ECT? Then changes cold startup depending on external temp readings? If so, it can't know external temp if it's been a short time between ignition cycles. What does it do in that situation? It seems kind of weird there's no plausibility (compare to another sensor, calculated value) or fail safe check. Why -41C? Just seems like it should have thrown a code... did it but it was a soft code, no lamp was thrown? Just trying to understand the logic/reasoning behind it better. This is puzzling.... I've personally seen them toss a "Cooling System Performance Malfunction" CEL for when the cooling system fails to reach xxx temp in xx time or fails to reach xx within xx of operation ect. ect. Who knows what happens on that generation, but it seems unlikely that the CTS could see -41 when logically your external temp, or even IAT is above 50 Fahrenheit. Should have tripped some logic. Quote Link to comment Share on other sites More sharing options...
Trouble Maker Posted December 9, 2012 Report Share Posted December 9, 2012 I've personally seen them toss a "Cooling System Performance Malfunction" CEL for when the cooling system fails to reach xxx temp in xx time or fails to reach xx within xx of operation ect. ect. What year/gen of FI ECU was that? A vehicle from m/y 2000 would have FI logic developed in the mid-late 90s.... maybe they just didn't have it 100% figured out by then. It's even possible that with it being an n/a Passatt it was using previous gen FI logic/ECU. Then they saw this, and probably many other issues in the market and added additional fail/safe logic to later systems. Quote Link to comment Share on other sites More sharing options...
Mr. Jones Posted December 9, 2012 Report Share Posted December 9, 2012 What year/gen of FI ECU was that? A vehicle from m/y 2000 would have FI logic developed in the mid-late 90s.... maybe they just didn't have it 100% figured out by then. It's even possible that with it being an n/a Passatt it was using previous gen FI logic/ECU. Then they saw this, and probably many other issues in the market and added additional fail/safe logic to later systems. 06 (Bosch ME9) Quote Link to comment Share on other sites More sharing options...
Trouble Maker Posted December 9, 2012 Report Share Posted December 9, 2012 06 (Bosch ME9) B7 A4 LOL Quote Link to comment Share on other sites More sharing options...
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