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Model specific boards => Golf mk2 => Topic started by: james_16v on 26 March 2009, 18:33

Title: Valver revs go crazy at warm idle
Post by: james_16v on 26 March 2009, 18:33
Just when I thought I sorted my idle troubles the past 2 days its developed an embarrassing new problem. When up to temperature and I dip the clutch the revs often stick then start bouncing around very erratically. Sometimes it will idle steadily (1000rpm) then increase to 3000rpm then randomly up and down from with the rev counter needle going mental.
The rev counter also show revs dipping to 0 although it has never cut out whilst doing it.
I have no clue what to try next ISV is fine, 3 temp senders are fine microswitch clicks when off throttle, cable not sticking etc.
Anybody have any suggestions?
Title: Re: Valver revs go crazy at warm idle
Post by: monzablue16v on 26 March 2009, 23:55
Bad earth I would say buddy, check all the earth straps and mounting points for breaks and rusty bolts etc. Temp sensors was my first though but not with the rev counter. Could be a faulty coil I suppose or Hall sender?
Title: Re: Valver revs go crazy at warm idle
Post by: james_16v on 27 March 2009, 11:09
Had a nose around this morning and one of the temp sensor heads fell off when checking the connections. I have 3 new GSF senders in the house but didn’t have time to fit them as I had to get to work, so just swapped it for the temp gauge sender. This didn’t cure it though.
The main earth on the gearbox is looking pretty grimy and the wiring to the temp senders and hall sender have seen better days (lots of frayed wires).
Ill clean up all earths, fit a new temp sensor, sort out the exposed wiring and crimp on a few fresh connectors on the weekend and see where that gets me.
Thanks for the suggestions monza  :smiley:
Title: Re: Valver revs go crazy at warm idle
Post by: monzablue16v on 27 March 2009, 11:57
No worries, let me know how you get on with it as I chased a similar fault for ages, changed the ecu, ISV box, Ignition amp, ISV allsorts. Changed the temp sensors and it never happened again :tongue:
Title: Re: Valver revs go crazy at warm idle
Post by: james_16v on 27 March 2009, 13:21
Will do fella
Must be a common fault with these monza blues eh??  :grin:
Title: Re: Valver revs go crazy at warm idle
Post by: monzablue16v on 27 March 2009, 13:22
It's because they are so awesome!
Title: Re: Valver revs go crazy at warm idle
Post by: james_16v on 27 March 2009, 13:33
Update - Just had a look at the coil and there seems to be a missing wire???
(http://i608.photobucket.com/albums/tt161/james_16v/DSC00229.jpg)
Worst part is I cant see any trailing wire to reconnect to :sad:
Anyone know where this should connect to???
Title: Re: Valver revs go crazy at warm idle
Post by: maxp on 27 March 2009, 14:55
Had a nose around this morning and one of the temp sensor heads fell off when checking the connections. I have 3 new GSF senders in the house but didn’t have time to fit them as I had to get to work, so just swapped it for the temp gauge sender. This didn’t cure it though. ...

I dont think they are supposed to be interchangable?
Title: Re: Valver revs go crazy at warm idle
Post by: james_16v on 27 March 2009, 20:09
Im pretty sure all 3 on the side of the head are the same part & resistance so are interchangeable.
I swapped them around this morning and it ran exactly as it did before (albeit without my temp gauge working!) so I think my fault lies somewhere else.
Ill investigate further tomorrow  :smiley:
Title: Re: Valver revs go crazy at warm idle
Post by: rubjonny on 30 March 2009, 10:30
that plug on coil is supposed to look like that, it is there to stop the coil terminal earthing out, as it is live with the ign. you are correct all 3 sensors on side o head are (should be!) the same :)

check your idle switch clicks, and the wires to it are ok
Title: Re: Valver revs go crazy at warm idle
Post by: james_16v on 31 March 2009, 13:38
All sorted!
Cleaned up and vaselined the main gearbox earth, replaced two of the temp sensors (left the coolant temp as its fairly accurate), fresh connections on all and used some heat shrink to cover the exposed wires and all is good. Not sure what out of that list actually cured it but it all needed doing so am happy again.
Glad to hear theres nothing wrong with my coil either, got a little stressed trying to find a trailing wire in the bay for!
Cheers to all who helped priceless info as usual.
Title: Re: Valver revs go crazy at warm idle
Post by: monzablue16v on 31 March 2009, 19:37
Nice one :)