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Model specific boards => Golf mk3 => Topic started by: Christo77 on 22 October 2012, 18:27

Title: Annoying off throttle oddness..
Post by: Christo77 on 22 October 2012, 18:27
I have searched around but it is an odd situation admittedly,

That is.. under throttle load, say accelerating up a steady incline.. just as i release accelerator to change gear i get a momentary increase/lurch in engine power! it's become annoying.
Infact if i load the engine on purpose i can carefully lift of the accelerator in the right way and it's like i've got an extra 10bhp or so (for a few moments) ..it's stupid i know!

It's a bit like the engine is only recognizing full power on initial throttle release..
Can only think it might be throttle body/ecu related but i've done all the tricks..
Cleaned TB
Replaced Fuel/Ecu relays.
Replaced T cable

Any ideas welcome!
Title: Re: Annoying off throttle oddness..
Post by: thai-wronghorse on 22 October 2012, 20:30
Have you checked the engine mounts for excess play?
Title: Re: Annoying off throttle oddness..
Post by: Christo77 on 23 October 2012, 09:30
That's a good call.. the one at the front being a usual suspect however, they seem ok and my vw mechanic would have picked up on it i'm sure if that was the case..
Thanks

Christo
Title: Re: Annoying off throttle oddness..
Post by: Len on 24 October 2012, 09:07
Mounts wouldnt give the surge of power he describes.

I would get a Vagcom check done. (diagnostics)
Title: Re: Annoying off throttle oddness..
Post by: javalin on 24 October 2012, 09:56
I had similar (lift off throttle issue) on a Fiesta, when you lift off there is a temporary vacuum created in the intake/engine and draws air/oil/etc into the engine.  The fiesta went rich as it was drawing in hot oil gasses from the crankcase breathers and then stalled....

I would check your engine breathers, particularly the crank case breathers (on the front) and see what you find...  Also the carbon canister.

James
Title: Re: Annoying off throttle oddness..
Post by: Christo77 on 24 October 2012, 14:58
I've been pretty meticulous to all the problems areas with these cars, and yep your right with the breather pipes but done it all, including the bung/spaceship on the top of the cam cover.
Also changed the plugs recently and they looked spot on condition wise, if that's anything to go by.
I guess next time i get to my vw chap i'll ask for a diagnostic, although i have a feeling he'll say there's nothing showing/nothing wrong.. because general running and visual inspections says it's absolutely fine!

It's just you really prefer to have all the engine power with your foot down, not off!  so that's a bit of a strange bugger.

Thanks for the help n suggestions

Title: Re: Annoying off throttle oddness..
Post by: tweed on 24 October 2012, 15:17
Throttle cable
Title: Re: Annoying off throttle oddness..
Post by: thai-wronghorse on 24 October 2012, 18:37
He's replaced it though.  :undecided:
Title: Re: Annoying off throttle oddness..
Post by: Christo77 on 24 October 2012, 20:16
I did yep.. and it was the same with the old cable, infact the old cable was perfectly fine really.. i just replaced throttle and clutch cable at the time for good measure.. and a bit of hope on the matter.
Title: Re: Annoying off throttle oddness..
Post by: VW BUSH on 24 October 2012, 21:24
Reset/check the TB on vagcom, I had a similar issue once worth a try :smiley:
Title: Re: Annoying off throttle oddness..
Post by: Christo77 on 25 October 2012, 14:03
If i had vagcom no doubt i'd have gone straight to it, although as far as i understand there's nothing to reset if there's an ISV circuit in the system.
Disconnecting the battery leads is another shot, have done that many times in the course of everything though.
No worries guys, i guess i'll live with it for now.

Thanks
Christo
Title: Re: Annoying off throttle oddness..
Post by: javalin on 25 October 2012, 14:10
dodgy wiring on the throttle sensor, or a faulty sensor itself?
Title: Re: Annoying off throttle oddness..
Post by: Christo77 on 25 October 2012, 21:34
My feeling is that it's more an electro mechanical type fault than a pure electronic one..
It could be a sensor.. i've done/replaced all i know, it'll just have to wait until i can get a proper diagnostic on the situation, take it from there.

Thanks