acceleration issues with 99 vw passat

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rasczak

Lifer
Jan 29, 2005
10,437
23
81
Originally posted by: T2urtle
P0103 MAF or VAF a circuit high input

is caused by you disconnecting it most likely

I should've been a bit more specific. I unplugged the MAF after I got the codes. Since I've only had the problems sparingly at best. (took the car out on a drive and only had the choking twice as opposed to previously when it would happen with a lot more regularity.)
So how did the vac lines look like? anything rotted thru?

Didn't check the vac lines. forgot all about them after above.


here might give you a better idea of what your problem can be as well.. pretty much what i was stating thru out the thread.

http://www.passatworld.com/for...howthread.php?t=166171

 

T2urtle

Diamond Member
Oct 18, 2004
3,432
3
81
MUST CHECK LINES!!!! CHEAPEST and EASIEST to repair. total cost and time to do every single line is say $15 and 1 hour.

well if you got a MAF code and your running rich it points more to either a MAF that is about to blow and/or a boost leak. This is all going to repeat itself but those are the reasons why you might get a combo of those 2 codes. It sounds like an extremely fixable issue that shouldn't cost you too much. More time consuming then physical labor.
 

rasczak

Lifer
Jan 29, 2005
10,437
23
81
Originally posted by: T2urtle
MUST CHECK LINES!!!! CHEAPEST and EASIEST to repair. total cost and time to do every single line is say $15 and 1 hour.

well if you got a MAF code and your running rich it points more to either a MAF that is about to blow and/or a boost leak. This is all going to repeat itself but those are the reasons why you might get a combo of those 2 codes. It sounds like an extremely fixable issue that shouldn't cost you too much. More time consuming then physical labor.

i've got the chilton's book but it's not very descriptive as far as what or where the vac lines are.

joe
 

T2urtle

Diamond Member
Oct 18, 2004
3,432
3
81
if you know what a vac line looks like. Then just simply trace what you can see.. rather then use chilton's because those books aren't 100% correct. yea the make things easier but they aren't exactly correct. Just eye ball things. Unless you find a LOOSE/ broken line then yea..
 

rasczak

Lifer
Jan 29, 2005
10,437
23
81
Originally posted by: T2urtle
if you know what a vac line looks like. Then just simply trace what you can see.. rather then use chilton's because those books aren't 100% correct. yea the make things easier but they aren't exactly correct. Just eye ball things. Unless you find a LOOSE/ broken line then yea..

I replaced all the bad hoses. still having the same issues. even with MAF disconnected. I'm thinking of going at the fuel pump now. Suggestions?
 

alpineranger

Senior member
Feb 3, 2001
701
0
76
A bad fuel pump would give you a lean condition, not a rich one. If you can get ahold of a scantool with live data you can check the short and long term fuel trim values to see what is going on (these will also show you o2 sensor voltage, so you can check if one is really bad). You should also check fuel rail pressure under load spikes to get confirmation of this before you remove the fuel pump. Because it's so expensive and in such an inconvenient place, you wouldn't want to do the job and find out that that's not the issue.

There are a few other things you can do that are low cost and low effort and will help you pin down the problem and eliminate possibilities. Propane enrichment test will check for leaks, not only in the vacuum system, but with compromised gaskets and cracked intake parts. You should try cleaning the MAF too, it's easy and you ought to do it anyways. The coils may be bad. Try checking the resistances - I've seen these things go considerably out of spec without codes before problems like misfiring happen.