Idle Increase when coming to a standstill

[dainese]

My car will most of the time increase about 50rpm or so, after i have come to a standstill. I can hear and feel the increase. The fuel consumption metre jumps from the usual 0.9L/100Km to 2.0L/100Km. It increases for a period of about 7-8 seconds and then goes back down to normal.

I think this happened after I cleaned the air filter which was a carbonio with a cone pod filter. Incidently, the filter wasn't changed for 2 years or so.


Any help would be appreciated.

Thanks a lot.

Justin

[McDub]

idle problems can sometimes be the MAF, so hopefully you didn't play around with it like i did...

[dainese]

hehe

Yeah, i read your thread thouroughly!

[Manaz]

Try turning your A/C off and see if it still happens...

[dainese]

it was off.

i don't use it much anyway.

[mikinoz]

At night with the lights on or all the time?

[Golf Loon]

Also try turning the steering lock to lock.
The p/s pump has a switch on it that can adjust the idle.

[dainese]

At night with the lights on or all the time?

all the time!

soemthing to do with electronics, the Air fuel ratio must change when car is idling, and some reason it isn't doing it properly.

Also try turning the steering lock to lock.
The p/s pump has a switch on it that can adjust the idle.

i don't understand how that will be related.
the P/S does have a pressure relief valve... but I am not steering at any angle when this problem occurs.

[Preen59]

The PS pump puts load on the engine, so it has to increase the throttle position to take the extra load and stop the engine from stalling when you turn the wheel if the engine is at idle. If you have a dodgey or sticky switch, it could be staying engaged, hence the increase in RPM..

[graeme86]

Can you hear a sort of whistling fan noise?

Could just be the secondary air pump coming on.

[dainese]

The PS pump puts load on the engine, so it has to increase the throttle position to take the extra load and stop the engine from stalling when you turn the wheel if the engine is at idle. If you have a dodgey or sticky switch, it could be staying engaged, hence the increase in RPM..

ah k, yes of course.

im pretty sure revs do increase when i lock the wheel. will check again.

Thanks

Can you hear a sort of whistling fan noise?

Could just be the secondary air pump coming on.

the air pump i only hear on cold start. and it sounds like a vacuum cleaner.

but now that you mention it. such a slight increase in rpm would not warrant so much noise (that it currently is exhibiting).

hmm.

might need the vagcom thing.
there is no cheap alternative to attaining that piece of gear?

[Treza360]

So I had a quick check today when I got home and the car was at normal operating temperature. Regardless of whether any of the lights were on, air conditioning was on the revs barely changed.

As for VAG-COM you can pick up a V-Checker Pro hand held unit quite cheaply (~$115). Fuzion might still have a couple lying around or you can buy one from ECS or that place that's selling the VAG-Tacho cheap. It doesn't do logging but at least you can view things normally and check for any faults.

Cheers,
Trent

[Andrew_Geo]

Is your foot oon the brake?


Could be a vacuum leak.

[dainese]

So I had a quick check today when I got home and the car was at normal operating temperature. Regardless of whether any of the lights were on, air conditioning was on the revs barely changed.

As for VAG-COM you can pick up a V-Checker Pro hand held unit quite cheaply (~$115). Fuzion might still have a couple lying around or you can buy one from ECS or that place that's selling the VAG-Tacho cheap. It doesn't do logging but at least you can view things normally and check for any faults.

Cheers,
Trent

thanks.

Fuzion is a member here? The handheld units scan for all codes, do they?

Is your foot oon the brake?


Could be a vacuum leak.

yeah, brake is on.

I think we need to scan for codes.

[Treza360]

thanks.
Fuzion is a member here? The handheld units scan for all codes, do they?

Yes and yes. Fuzion has one of the best looking MkIVs in Australia.

http://www.vwwatercooled.org.au/newforum/upload/showthread.php?t=34008

Cheers,
Trent