high idle-faulty throttle body

[silverdovegti]

hey,

recently on a few seperate occations, i've had my engine idle higher than normal (at around 1400) just randomly even though the engine is already heated up to its optimal operating temperature after 20mins or so of driving. the only way i found to fix the problem was to restart the car at the lights! the accelerator pedal does not seem to be stuck. i've got an 2004 gti (stock). anyone else had this happen to them?

*i know when warming up the engine revs higher (1200) for a few minutes then returns to the normal idle speed of about 800.

at my last service i informed the dealer about the problem and they "carried out basic settings & throttle body clean and checked engine management data". it seemed to have solved the problem but now 3 months after that i'm getting the same problem. any idea what could be wrong?

also another related question. at 4 degrees or cooler when the "snowflake" indicator comes on, does the car automatically rev higher when idle at about 1100 or does it just operate as per normal?

any advice would be appreciated! thanks!

[benissatan]

erm not to sure if its this or not..
but i had the same problem where my car was idling at 2 thousand revs. and it was just in need of a new battery. it was creating power surges. and just making it genually rev over 2 thousand revs...
ohwell possibly could be it.. i donno.

[gpk_gti]

sounds odd,no aircon on?? did the dealer say there was any fault codes? could be a maf failure? mine was going to stall not rev higher,but those dam things could cause anything!
I dont have the snowflake,,I might but it hasnt come on yet.doubt that would be your problem.my car idles higher for only 1 min or less then goes to normal.

[ope126]

http://www.vwwatercooled.org.au/newforum/upload/showthread.php?t=5681

The search button is your friend...:D

Glenn

[silverdovegti]

thanks ben & gpk, yeah a/c wasn't on... battery sounds like a possibility as i'm probably due for a new one soon. will bring the car in sometime next week and see what they say. :)

oh and special mention must go to glenn (ope126) for introducing me to his friend, the search button. just in case you missed it i did mention that this issue is not that of the engine idling higher from a cold start as discussed in the thread you found. you should meet my friend... he's an optometrist. :rolleyes:

[mikinoz]

Try cleaning the MAF (in the intake) with contact cleaner as sometimes this can be fouled over time and give incorrect readings resulting in idle differences, I had this in my MKIV once upon a time.

[ope126]

thanks ben & gpk, yeah a/c wasn't on... battery sounds like a possibility as i'm probably due for a new one soon. will bring the car in sometime next week and see what they say. :)

oh and special mention must go to glenn (ope126) for introducing me to his friend, the search button. just in case you missed it i did mention that this issue is not that of the engine idling higher from a cold start as discussed in the thread you found. you should meet my friend... he's an optometrist. :rolleyes:

Just today I have noticed that at nomal operating temperaure that the idle speed remains quite high (1200 - 1400rpm) for about 5sec, then drops to 900rpm. (say stoping at the traffic lights)

Is this something to do with the Throttle Body Alignment Fault Code?

Has anyone else experienced this?

Mate, the above is an extract from my post. I never once mentioned a "Cold Start" that was never the problem. Here I am trying to give you some helpful advice, maybe you should be contacting OPSM yourself!

Anyway, no hard feeling...
Welcome to the site!!! :D

[ope126]

Also, a mate of mine with an 04' GTI has also experienced similar problems. He was told that it was a faulty Throttle Body, this was also effecting his cruise control. Are you having problems with your cruise control also?

[gpk_gti]

haha,,good one guys..try the maf clean as mikinoz suggested,but it doesnt work iv seen on the net and been told by numerous mechs.I did try it myself but did not help.remember to dry with cold air,,as in blow dryer or compressor. as for the throttle body,there is a set of reset codes that the VAGCOM can do to check that all is fine..I doubt it could be your battery as usually your revs will start to drop,no??

[gpk_gti]

at my last service i informed the dealer about the problem and they "carried out basic settings & throttle body clean and checked engine management data". it seemed to have solved the problem but now 3 months after that i'm getting the same problem. any idea what could be wrong?

!

hmmm,just rereading your original post.sounds like it is associated with the throttle body.bad fuel maybe has left residue in the body somewhere? def id be doing a reset before checking anywhere else.where are you located exactly?

[gtimk5]

Its a regular service thing to clean out the throttle body by taking off the intake pipe and cleaning around the butterfly area with something like "Wynns throttle body cleaner" in a spray can and using compressed air. A soft rag while holding the butterfly open aids this as well but be careful not to damage anything in there!
Also, check for any air leaks.,...
Get it checked for fault codes is a neccesity.
Cheers, Andrew :)

[silverdovegti]

thing is this doesn't happen all the time. it happened yesterday and before that it was 2 weeks ago. i fear that when i bring the car in (probably monday) she will start behaving and the mechs won't be able to see anything wrong with it?!

ope126: don't really use cruise control so not sure, will give it a go and let you know. yeah no hard feelings mate.

gpk: engine works as it should (revs drop after a minute) most of the time. the car has always run on 98 ron, i assume bad fuel can't be the problem? very particular with fuel so only use bp ultimate or vortex. i'm a complete novice when it comes to working with engine related issues, should i try to clean the throttle body myself or is it safer to bring it in? re the vagcom check, would there be a charge to get that done? i'm in the eastern suburns melbourne, i service at barlowworld glen waverly. :)

[silverdovegti]

turns out it was a faulty throttle body. the car was a few months out of warranty but the dealer replaced the part free of charge. just fyi... :)

[gpk_gti]

thanks silverdovegti!!!! we will be stickying this thread!!! did they say the TB was reset or changed??

[ope126]

Well done if that is the case...
I was told that these are $1500 parts (throttle body) :D

Glenn

[silverdovegti]

gpk: when i initially told them about the problem at my last service they reset and cleaned the throttle body, but since then the problem recurred (after being ok for about 3 months) so they replaced the faulty TB this time round. :)

[Golf Loon]

I have a couple of mates at the main dealer and apparrently VW usually change em under warranty, but often if cleaned they are still operational.
I`d definately try that first as they are dear.

[mikinoz]

thanks silverdovegti!!!! we will be stickying this thread!!! did they say the TB was reset or changed??

Added to FAQ and DIY!

[h100vw]

Is the snowflake not a warning of possible icing conditions. Used to get one on my Passat in the UK for that reason. I bet it would mention it in the car handbook.

Gavin

[NGOLF.U]

happend to me but it was just a vacuum leak

[geoff_gti]

yeah i've had the same problem with the revs jumping around between 1200 and 1400. my mechanic did clean out the throttle body etc and said if it continued to reoccur i would need to get a new TB which isn't cheap. when ever it happens my cruise control won't work either, only quick fix is to cut the engine and restart i've found

[bert]

Exactly whats happening to me right now (including cruise control not working), however happens all the time and revs really lurching around between 1200-1600 RPM at idle and car hops around whilst driving at very slow speed.

Diagnostics returned error codes:

1) throttle control lower limit not reached
2) throttle control module internal fault

In the process of sourcing a new TB.

[geoff_gti]

Good ol' TBs!
I often feel when my goes on the blink too - I'll be sitting at the lights with my foot on the brake, the pedal drops a little bit under my foot & then the idle start going up... lol. Not always but I have noticed it sometimes. (PS brakes continue to work fine after, must just be a slight dip in the pressure fot that instant...)

[datracer99]

happend to me but it was just a vacuum leak

Hi
Sorry to bring back an old thread, but I've just started having idle issues with my 2007 MkV GTI.
Vagcom indicates an air leak, so possibly same issue as NGOLF.U
Just wondering if I can get any ideas on where to look for the air leak. Are there any common pipes which fail early?

Thanks
David

[Morry]

Mines doing the exact same thing (2000 MK4 Golf 2L 5spd) so ill be looking at cleaning the TB soon and hoping its a small air leak after the MAF.

[JustCruisn]

The air leak is likely to be in a vac line not the intake air flow.
Check all lines near the throttle body and brake booster.

[karmen]

what fuel and how many k's on it may be a lead (leed not lead metal)

[h100vw]

what fuel and how many k's on it may be a lead (leed not lead metal)

Did you intend to reply to a post that's 7 years old??

[karmen]

did not see that but others can benefit
guess that's why we keep the threads that long almost as long as the ole cars, cheers, K