00_Passat Check Engine Light

[Reg151]

Hey my check engine light came on w/ the dash message reading "emissions workshop". . . any idea on what the problem might be? 0-2 sensor maybe? Thanks!

[jesira]

The same thing just happened with my 2000 Passat. Brought it to my mechanic (not VW), and he found nothing wrong with the car after extensive diagnostics. Reset the computer, the light disappeared, then reappeared on the same day.

Mechanic said to take it to VW, and now I have to go through the whole thing again with them trying to diagnose the issue and spend more money.

My mechanic said this is an ongoing issue with the Passats, a thorn in VW's side, and that b/c it's related to emissions, the work is covered under a broader legislative (i.e., not VW) warranty of 50k/5 years. VW denied it, saying that the problem could be anything, not necessarily related to emissions and hence, not necessarily covered under warranty.

Anyone have anymore experiences/advice to share???

[hutchsn]

I have a '00 Passat 1.8T which had the same problem... At first the problem was intermittent and the VW dealership would reset the code and it would happen again after a few days.
Eventually it got much worse and I noticed some hesitation when accelerating. A private mechanic (ex VW) ran diagnostics on it and recorded a 'misfire error code' which points to the ignition coils. I replaced #2 and it has been fine.
Note: There is a known issue with these ignition coils and they might be replaced under warranty if your serial number falls within the proper range. Otherwise they sell for around $100Cdn each + labour to install

[wagonboy]

ok, i have the same "emmissions workshop" light.

- one dealer, while repairing the fuel pump thing in the gas tank, found a bad sensor. they said it was not the O2 sensor, but did not specify other than that, and beat around the bush when i asked what it did. he said it was not urgent to replace, but would cost about $350. plus, he said that he couldn't be sure that the bad sensor was the cause of the "check engine" light. i decided to wait.

- about half a year later i had a 40k check at a diffferent dealer and she said the engine was running lean, but did not know the cause. she recommended cleaning the fuel injectors and throttle body (something like $250). again, she did not know if this was the cause of the light.

- about a month after that, i went to a shop for a smog check. it failed because of the engine light (don't ask why the mechanic went ahead with the check when he knew it wouldn't pass). his diagnostic machine gave a fault code of P1137. he wanted to charge me to find out what it meant. i declined.

so here i am, not knowing who to trust, and needing to pass the smog check because my registration is up.

any input welcome!

[boschmann]

P1137 is for the long term fuel trim being too rich for bank one, was there a P1139 also (same for bank 2)? If it's only the one code I'd suspect the pre-cat bank 1 O2 sensor is bad, but you should let someone familiar with VW's diagnose it properly.

[drivingvw]

go to ross-tech.com. everything you ever wanted to know about vw/audi diagnostics codes. They also sell an interface that lets you use your own PC as a diagnostic tool. Also check out vwvortex.com-great forum for all things vw/audi!

[wagonboy]

I finally just took it to a dealer expecting to pay $300-400 for a fix. The problem was a bad "air flow sensor." Amazingly, it was somehow under warranty (this is a 2000 model).

The engine now runs noticibly smoother, and I'm getting about an extra 50 miles per tank of gas.

[mbogosia]

That is so typical of a vw. How does a Mass Air flow sensor go bad on a 2000 model car! Absolutley insane.

[Morivard]

Originally Posted by boschmann

P1137 is for the long term fuel trim being too rich for bank one, was there a P1139 also (same for bank 2)? If it's only the one code I'd suspect the pre-cat bank 1 O2 sensor is bad, but you should let someone familiar with VW's diagnose it properly.

Never used forum before so I hope this works. I have the same light. VW says I need a new catalytic converter at a cost of $2000! WHat's the worst thing that can happen if I just ignore the light?

[boschmann]

The same light is used for alot of things, did they tell you any codes they pulled? If you're less than 80K miles the cat is under federal warranty. Driving with an inefficient cat isn't that bad, but there may be a reason the cat went bad that should be addressed.

[Morivard]

Originally Posted by boschmann

The same light is used for alot of things, did they tell you any codes they pulled? If you're less than 80K miles the cat is under federal warranty. Driving with an inefficient cat isn't that bad, but there may be a reason the cat went bad that should be addressed.

They said the light might be on because I need both cats changed (3000 total) or purge valve (400). Or they said they could "clear the codes", which is what my husband told them to do. Yet the light has now reappeared (less than 1 day after the service. I found 2900 "hits" on google for Passat check engine light problems. Sounds like people bring their cars in multiple times and in many cases get repair after repair and the light reappears. ALso seems VW will take no responsibility and my car is over 80k unfortunately. I'm afraid to have them change the purge valve and then there will be something else! I sure appreciate your guidance. What many peoople on the sites seem to be doing is getting the light successfully turned off and unloading the car. Seems unethical but I feel like I'm being forced into something like that...... Thanks! Marianne

[boschmann]

Most Autozone and some Advanced Auto Parts stores keep generic scanners that can get the trouble codes read for you for free. Post them & I can try to interpret. Yes, check engine lights on VW's is a pretty common thing.

[Morivard]

Thank you Mr. Boschmann. I will do just that!

[wwh975]

I was reading on another forum that there might be a 50 amp fuse/relay that might need cleaning. The people on this forum were talking about a little older car (1996-97) than a 2000. The gave a description of where to find this fuse inside the engine compartment, but I am not sure if it is in the same location for a 2000. I looked in mine and could not find a fuse. I am pretty sure it is because I have no clue about engines. Could someone shed some light as to where this fuse might be located in a 2000 passat. I would much rather try this fix than take it to a dealer to get it fixed. Thanks.