Dub newcomer - GTi MkIV

[bert]

your mechanic obviously reset the codes, but you need to reset the basic settings then reteach it. its pretty easy. you need vagcom though. if you have or your mechanic has vagcom ill put up how to do it

Cheers PeDiES.

Quote from the written report:

"Checked engine idle fluctuating. Checked stored computer fault codes and indication of faults in throttle assembly. Removed air intake and cleaned throttle assembly thoroughly. Refit throttle and carried out full engine and throttle adaption reset. Erased stored computer fault codes and roadtest for operation."

Then the fault codes kept returning and the idle is still fluctuating/too high...

Thoughts?

[geoff_gti]

Hey Bert,

Sounds like the guy must have a VAG COM if he's been able to check the codes... (VAG COM is the service interface for recent Dubs & Audis - software on a laptop talks back to the computer in the car - the port is located under the removable panel beneath the stereo if you're curious )

Not too cluey on this stuff either, but sounds like the throttle body sensor is on the way out - that would trigger a faulty reading & then engine goes rough. Don't think the throttle wouldn't have it's own computer as such so making the assumption it's a sensor not reading correctly. Not too uncommon on Mk IV's

There is also a 'reset' process (throttle body alignment) which has to be carried out if the battery has been removed etc or presumably if the tb has been removed. Not sure if this is what the service report is referring to when he says 'adaption reset' ??

If it has been reset & cleaned a few times, then it probably will keep faulting. I don't think it will cause any harm though, it's just annoying. Mine's the same intermittently too.

Link to throttle body alignment info: http://www.ross-tech.com/vag-com/cars/throttlebody.html
Have a look through Ross Tech for all the other stuff you can do with VAG COM too


edit: just saw your wtb thread, hope you find one at a reasonable price

[bert]

Not too cluey on this stuff either, but sounds like the throttle body sensor is on the way out - that would trigger a faulty reading & then engine goes rough. Don't think the throttle wouldn't have it's own computer as such so making the assumption it's a sensor not reading correctly. Not too uncommon on Mk IV's

Cheers Geoff.

Do you know if it is possible to just replace the sensor without replacing the whole throttle body? What would be the VAG part number for this?

EDIT: HAve had a poke around. Would this be the appropriate sensor for a '99 GTI with cruise control:

http://www.autopartswarehouse.com/de...3-1609690.html

[geoff_gti]

Sounds like you're on the right track but I wouldn't take my word for it

[h100vw]

Cheers Geoff.

Do you know if it is possible to just replace the sensor without replacing the whole throttle body? What would be the VAG part number for this?

EDIT: HAve had a poke around. Would this be the appropriate sensor for a '99 GTI with cruise control:

http://www.autopartswarehouse.com/de...3-1609690.html

Not what you need, sorry. I don't know that you can buy individual TB parts for this fix.

Gavin

[bert]

Not what you need, sorry. I don't know that you can buy individual TB parts for this fix.

Gavin

So you think that replacing the whole TB is the go? I don't mind forking out for the whole unit as long as I can be assured that it will fix the problem.

Cheers

[h100vw]

So you think that replacing the whole TB is the go? I don't mind forking out for the whole unit as long as I can be assured that it will fix the problem.

Cheers

That assurance would be based on accurate diagnosis mate.

I know the bit is pretty pricey. Finding someone local that would lend you a good one to try would be one option that I would look into.

If you find that fixes it then green light is on to buy your own. Nothing more demoralising than spending loads on the wrong parts.

Gavin


EDIT I don't suppose you have the codes that your man got from the computer?????

[bert]

EDIT I don't suppose you have the codes that your man got from the computer?????

Not currently but I'll chase it up.

[bert]

Emailed the mechanic and pleasantly surprised that I got the response I was after. I wasn't 100% satisfied with them first time around but after this nice piece of Customer Service I might head back there. Their reply to my request for the fault codes that were appearing was as follows:

"In regards to your query regarding the computer error codes, they were reported to be as follows:
1) throttle control lower limit not reached
2) throttle control module internal fault.
3) codes were unable to be cleared."

Thoughts?

[SpeciP3]

Sound like a sensor mate.
My brother had the same problem with his MkIV, the codes cannot be cleared until the faulty part has been replaced or disconnected, but yes sensors will make it run rough.
He also had to replace the throttle bodies at around the same amount of K's you are at now so could be either.
good luck either way