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Model specific boards => Golf mk2 => Topic started by: maxp on 17 May 2010, 20:06

Title: Very high idle [vid]
Post by: maxp on 17 May 2010, 20:06
Ive tried a few different ISV's but they all seem to be letting far too much air into the engine.

Here is a vid of my engine with the throttle switch disconnected (this tells the ecu that the engine is no longer at idle).

http://www.youtube.com/watch?v=arqmwcY235w

Any clues from anyone as to why it's so high would be helpful.

Ive changed the throttle body, throttle body gasket, isv, and the blue temp sender works.

Cambelt has not been changed but cant see how this would trigger this symptom.

It looks to me like for the first half a second the car is ok, then it just goes into over-rev.
Title: Re: Very high idle [vid]
Post by: raferackstraw on 17 May 2010, 20:17
vacuum hoses? or its letting in air some where? have you cheched intake boot etc for cracks etc?
Title: Re: Very high idle [vid]
Post by: maxp on 17 May 2010, 20:24
vacuum hoses? or its letting in air some where? have you cheched intake boot etc for cracks etc?

Ive replaced the big rubber hose running from the airbox to the intake throttle body, assume thats what you mean?
Ive also renewed the vac hose on the back of the throttle body, the blank one on the throttle body, and the hose running to the t-piece (fuel pressure regulator/airbox).

I think that's all of them?
Title: Re: Very high idle [vid]
Post by: raferackstraw on 17 May 2010, 20:36
im not sure on digifants m8 but does it have an idle screw? if so remove and check o ring is intact and give it and its hole a good clean, you may have to wait for dannyp or rubjohnny to comment
Title: Re: Very high idle [vid]
Post by: Sam on 17 May 2010, 21:05
Loving the classic gti fuel gauge position there
Title: Re: Very high idle [vid]
Post by: maxp on 17 May 2010, 22:52
Loving the classic gti fuel gauge position there
Lower the fuel = the faster the car  :tongue: :tongue: :tongue:
Title: Re: Very high idle [vid]
Post by: rubjonny on 18 May 2010, 08:15
why are you so hung up on what the car does with the idle switch disconnected? high idle is one of the symptoms you may get if the throttle switch is disconnected. what are the symptoms when the idle switch is connected
Title: Re: Very high idle [vid]
Post by: maxp on 18 May 2010, 08:55
why are you so hung up on what the car does with the idle switch disconnected? high idle is one of the symptoms you may get if the throttle switch is disconnected. what are the symptoms when the idle switch is connected
Sorry im aware im being abit annoying with this.
It is fine with the switch connected indeed, but when the accelerator goes past the throttle switch (ie not at idle) it surges rpm massively.

Meaning basically you have to drive everywhere on the clutch til you get past 15mph.
Title: Re: Very high idle [vid]
Post by: sprout99 on 18 May 2010, 09:50
after replacing all the split hoses and vaccuum pipes mine was running at about 1500 rpm
i had to turn the idle right down ......

typically if you have an air leak the revs will be harder to maintain so idle is adjusted to compensate

my prob was that i owund it back too far and found it cut out when stopping for junctions etc
Title: Re: Very high idle [vid]
Post by: rubjonny on 18 May 2010, 12:20
can you take us thru everything you have checked?
has the idle, co and ignition timing been reset as per the digifant faq? is it definitely the correct distributor fitted?  have you made sure there are no airleaks anywhere, and have you reset the throttle stop position as per the haynes? Also if throttle stop adjusted have you rechecked the idle switch and throttle cable adjustment afterwards. have you made sure the vacuum pipes are all correct, the one on the back of the tb and the one on the front, driver side should be capped off, the one on the passenger side of the tb should be connected to the FPR and the warm air feed flap.  Also have you double checked the static timing is correct?
Title: Re: Very high idle [vid]
Post by: Baylez8v on 18 May 2010, 12:41
i had same problem, unpluggin isv solved this..... :grin: bodge it and scarper
Title: Re: Very high idle [vid]
Post by: sprout99 on 18 May 2010, 12:52
i had same problem, unpluggin isv solved this..... :grin: bodge it and scarper

i've tried that....car cuts out  :huh:
Title: Re: Very high idle [vid]
Post by: Baylez8v on 19 May 2010, 10:27
bugger, i clearly have issues else where though so probably best not to listen to me anyway lol
Title: Re: Very high idle [vid]
Post by: maxp on 19 May 2010, 13:13
i had same problem, unpluggin isv solved this..... :grin: bodge it and scarper

i've tried that....car cuts out  :huh:
Mate, if you're looking to bodge it, and the car cuts out when you unplug the isv, you will need to unscrew the idle screw *way* more and you will get there eventually.