spooky revving - UPDATE

[STORM 2 0]

hi all

started her up this morning whilst I had a cup of coffee (bloody freezing this morning) but I noticed she started revving up quite harshly of her own accord.

Got in drove away once revs had settled to normal idle, then whenever I was in neutral, she started to rev again of her own doing, up to 3000rpm then settling back down to normal idle.

Later in the day she wouldnt start (engine was warm) ---- would turn over but wouldn't fire!! after several attempts she spluttered into life....

 

Am I looking at a new coilpack here?

 

already done so far:

 

new leads

new plugs

ECU reset done

 

h-e-l-p!

[STORM 2 0]

wot no takers??

[RS VR6 0]

Maybe check the stabilizer idle valve? Could need some cleaning...

[Henny 0]

yup, sounds to me like your ISV has been playing silly beggars, or you have an air leak somewhere... :|

[andy 0]

ISV for sure mate, I had exactly the same symptoms on my old Golf VR6, it was like someone was in it revving it when I was outside looking at the engine, turned out to be a bit of crap from the ISV sound deadner (next to the ISV) had got lodged in the ISV, it did happen once again but it turned out to be a bit of crap in the pipes leading to the ISV, so check them too!

[Adam Darby 0]

is it a 16 v i had a problem like this that took my ages to find. sometimes even whils driving in gear the revs would shoot up and down and sometimes the engine would die and would not start if a went back an hour later it would start fine it turned out to be the distrobutor, it has a kind of crank sensor on it that tells every thin wwhat position the engine is in and when to fire so sometimes it would not work sometimes it would give it wrong info i think it was about £120 exchange from euro parts ??

[STORM 2 0]

is it a 16 v

 

its a VR....

well I cleaned out the ISV as well as biting the bullet and sticking on a new coil pack (GSF / BERU -£115)

the revving seems to have settled but I still have the problem of rough running and jerkiness on acceleration. I also suspect she's running a little rich looking at the trip MPG

changed so far:

 

plugs

leads

coil pack

fuel filter

air filter

tried ECU reset - temp fix only

cleaned out ISV

 

Next step - - (could do with some help on this part!)

 

? lambda sensor

? fuel injectors

? replace fuel pump - - how easy is this considering its sitting in the tank?

 

This is really beginning to get me narked....

[Riley 0]

ok m8,im still learning about raddo's me self...

 

someone please correct me if wrong on the following :!:

 

can you have the lambda checked somehow?

a lambda value type gas anyliser thing??? :oops:

maybe replace to eliminate if cheap enough? anyone?

 

then id be suspecting the injectors,could be dripping fuel overnight,causing normally a bit of a missfire at first then clearing up,but it may be causing it to rev if the piston ring clearances are good and its holding the fuel? would have to leak quite a bit i suppose...

 

sorry if im talking sh1t,im a little drunk too :D

[vr6storm 0]

check yer coolant temp sensors too m8

[STORM 2 0]

check yer coolant temp sensors too m8

 

well done mate, you got it bang on there!!

 

had the coolant temp sender changed and all is well in the land of the Corrado......running sweet as the day she was born!! Better in fact, having spent hundreds replacing various bits and bobs.

 

Cheers!!

[STORM 2 0]

Well my intial enthusiasm turned to sheer bloody frustration a few days later when the same problem recurred with a vengeance :mad:

Anyway I've had a couple of interesting weeks with the car......after the problem came back, I lost all my coolant on the M27 through a 1mm split in the main coolant hose going into the block and had to call the RAC out for some amalgamating tape!

The car was booked into VW for some warranty work and one of the engineers ( a good guy ) had another look at the problem.....VAG-COM was now throwing up the Hall Sender as an intermittent problem. Turns out that VAGCOM doesn't always throw up this fault even if it is present - don't know why.

Anyway Richie in parts (another good guy who's found a VSR inlet for peanuts which he's grafting onto his Golf VR6) finds a Hall sender in Southampton and arranges for me to pick it up on Good Friday which I do (cost £30)

 

Friday I spend most of the day on the car:

 

1. Drain coolant - both by drain plug and by removing upper and lower radiator hoses. Took off expansion tank and scrubbed all the rusty crap out of it. Removed the damaged hose and replaced with new hose (from VW around £35 with CCGB discount).

BTW - if anyone has any trouble with the spring hose clips and doesn't want to fork out £100 for the Hazet pliers that VW use, I found some cheap ones in Halfords with made spring clip removal a doddle - they cost a tenner.

Anyway refilled with G12+ and circulated around the system.

 

2. removed radiator cowl to confirm that my thin V belt attaching powered fan ( on the right) to passive fan (on the left) was missing thus giving me only one fan. I already had this belt so i just put it on-5 minute job- so worth checking if youre running high temps)

 

3. Removed old Hall sensor ( right hand side of the camshaft) very easy to do once youve got the right hand side of the plastic inlet cover off. replaced with new part. Quick job about 15 minutes

 

Well I pleased to report after caning it up to Cardiff today ( for the Wales v Austria match) my efforts seem to have paid off.

 

Oil and water temperatures have remained 5-10 degrees lower (when pushing VERY hard)

 

misfiring has GONE (fingers crossed) and the idle is much smoother

 

power delivery is instant. So much so that having taken everything replaced into account, the car is punching much better than when I bought it.

 

Sorry I seem to have waffled on somewhat - but I hope this helps someone! I know rough running can be bloody frustrating but I think I've got to the bottom of this one finally. The real problem is when you get two or more problems at the same time and having one intermittently makes it more confusing. But I'd advise everyone who's scratching their heads to replace the cheap and easy things anyway - ie coolant sender and Hall sender, fuel filter, plugs and even HT leads.