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Model specific boards => Golf mk5 => Topic started by: grmair on 29 November 2008, 20:58

Title: Roaming revs at idle
Post by: grmair on 29 November 2008, 20:58

My Mk 5 GTI has started revving very randomly.  At idle the revs sit at about 1200 then rise to 2000 or 3000 over a few seconds, then returns to about 1200.  I can't be sure but it feels like it's lost some power too.  Any suggestions where to start looking would be appreciated.

Title: Re: Roaming revs at idle
Post by: Komenda on 29 November 2008, 21:06

One or more of the coil packs could be on their way out.

Title: Re: Roaming revs at idle
Post by: grmair on 30 November 2008, 18:48

Thanks Komenda,

It's a long story but i have had problems with them before. I had over-spec'd plugs in and they were burning out the coils.  It's possible that one was damaged at the time i sorted the plugs out and is only now showing the signs after degrading over time.  Is there a simple way to test the coils for damage? As far as i know they're packaged pretty tight. This one's a real annoyance!

Title: Re: Roaming revs at idle
Post by: bacillus on 30 November 2008, 19:01

Quote from: grmair on 30 November 2008, 18:48

Thanks Komenda,

I had over-spec'd plugs in and they were burning out the coils. 

What type of plugs??

Title: Re: Roaming revs at idle
Post by: grmair on 30 November 2008, 19:37

I put Denso Iridium's in.  They claimed to be suitable but they burned at too high temperature and blah blah blah.  I replaced it with proper standard Bosch Platinums and all was fixed.  All i can think of is if you're right, one of the coils was still damaged but has got worse over time.  Maybe it's that or maybe it's a completely new problem.  I'm scratching my head at the minute...

Title: Re: Roaming revs at idle
Post by: bacillus on 30 November 2008, 21:05

hmm, are you saying that your car idles at 1200rpm when warm?

Title: Re: Roaming revs at idle
Post by: Riz on 10 April 2009, 22:17

what was the Fix? i think i have coils

Title: Re: Roaming revs at idle
Post by: DanoGTI on 11 April 2009, 08:16

Just to add to the mix - fwiw, I had the same type of issue with my Scooby.
The MAF (Mass Air Flow) sensor was dirty/failing. Caused the performance to drop off (BIG time) and also the idling was erratic.

Personally, I'd still go the coilpacks, but it might be worth checking the MAF out too :)

HTH & "good luck"

Dan :)