Socrates75 0 Posted January 23, 2006 I've had a look through all your archieve stuff re this problem, but just want to ask what is the most common cause of this problem. The car has an irratic idle, but it tends to cut out when coming to lights and junctions etc. The car has been in and out of garages with this problem but to no avail, and one is a VW specialist! I've recently had the throttlebody removed and cleaned, it didn't need replacing and the MAF bit has also been cleaned thoroughly. I'm no mechanic, just want to point these muppets in the right(ish) direction! What next! Please help :? Oh yeah, the car is a 1995 VR6, super chipped running a full S/S zorst. Quote Share this post Link to post Share on other sites
Timo. 0 Posted January 23, 2006 idle stablization valve (ISV) probably needs cleaned out with carb cleaner. Its the usual suspect for vr's cutting out. Also the little pot thing that the throttle maechanism rests on when you come off the throttle could be to blame (not the best explaination!) Have a search for "ISV". You'll find loads of threads on it. T. Quote Share this post Link to post Share on other sites
Socrates75 0 Posted January 23, 2006 Nice one, is this ISV something I can do or is it a hard to find fiddly task? Scale out of 10! :D Quote Share this post Link to post Share on other sites
Timo. 0 Posted January 23, 2006 Easy mate. Its a road cylindrical shape electronic gizmo at the back of the vr engine, need to move the back plastic cover and you can quite easily get to it. Either take it off by un doing some pipes and load it full of carburator cleaner or you can blast it whilst still half connected. Personally I would take it off. You should get loads of black crap coming out once you let the carb cleaner do its stuff. It may solve the problem, but may not. A lot of vr's including mine occasionally stall, its another one of those things. Usually happens when you least expect/want it to happen. However if its happening alot a clean out of the ISV may help, otherwise it might need a new one :( T. Quote Share this post Link to post Share on other sites
Timo. 0 Posted January 23, 2006 Oh, 1 out of 10 difficulty rating. In fact its probably 0! :) T. Quote Share this post Link to post Share on other sites
Socrates75 0 Posted January 23, 2006 Sounds good to me! :D Just sick of dealing with it. A yank forum said disconnect it, the idle runs higher but should prevent prob... sounds a little harsh :up: Also perhaps a "Engine Speedo Sensor", ever heard of that? Quote Share this post Link to post Share on other sites
Timo. 0 Posted January 23, 2006 If your 'engine speed sensor' goes it wont run at all. Defo sounds like the ISV to me. Its a really common. T. Quote Share this post Link to post Share on other sites
Socrates75 0 Posted January 23, 2006 Cheers mate much appreciated! :) I'll have a go myself to avoid being killed by partner who hates the amount of coin going on the beast! :D Quote Share this post Link to post Share on other sites
Timo. 0 Posted January 23, 2006 no worries mate. Better keep the wife happy ;) T. Quote Share this post Link to post Share on other sites
fla 9 Posted January 24, 2006 Dont forget to relube the ISV carefully after cleaning it. Carb cleaner removes pretty much everything so you end up with metal against metal, which will deffo bind after a while. Might help to use something like Slick 50 or any other oil additive - thats about the only good use for those types of snake oil IMHO, but for these applications they're pretty good. ONly a few drops, mind you. Quote Share this post Link to post Share on other sites
Aus 0 Posted January 24, 2006 I had the same problem - seems adjusting the "little pot thing that the throttle maechanism rests on when you come off the throttle could be to blame (not the best explaination!) - Timo" did the trick for me! " min job and no cost! Quote Share this post Link to post Share on other sites
Supercharged 2 Posted January 24, 2006 There are 2 'engine speed sensors' but as said above, the crank sensor would not allow the car to run at all but only if completly dead, this also always comes up on VAGCOM if the engine is not running... Clean the Throttle Body and ISV by all means but I would have thought a garage would have checked these, we really need the VAGCOM readout in order to advise otherwise you are just clutching at straws... Quote Share this post Link to post Share on other sites
Socrates75 0 Posted January 24, 2006 Cheers :up: It's been on a computer and shown no faults across the sensors. I believe this ISV thing is potentially at fault. So, on Thurs, me, myself and I is gonna have a go. :D I'd be grateful of decent description of exactly what and where ISV is and where this pot like thing is and what to do with it :up: NICE ONE :D Quote Share this post Link to post Share on other sites
Socrates75 0 Posted January 24, 2006 The mobile in question :) Love it and hate it :D Quote Share this post Link to post Share on other sites
edd 0 Posted March 23, 2006 Did this get sorted?? Quote Share this post Link to post Share on other sites
Socrates75 0 Posted March 23, 2006 I bought an ISV and then the car decided to behave so it's been sat in my boot... But funnily enough the thing has started to play up today. I'm not wholey convinced that the ISV is at fault and if it isn't some fuel related problem... I mean, why sometimes does it run sweet as then other times lumpy as fcuk. I thought it could be when you're getting the dregs from the garages pumps in the tank. Surely that would be the equiv of running the car down to no fuel and dragging all the shit through the system? I've found it behave's a little better after a a real good twatting, when you take it to the max, then when back at lower revs it goes normal. I'll whack this ISV on and see what happens... I'd be grateful of any other suggestions... It has no sensor faults from a VAG comp for your info. :wink: Quote Share this post Link to post Share on other sites
edd 0 Posted March 24, 2006 Cheers for the update - just going through the exactly same issues! but refuse point blank to change a few items costing in excess off £600 from VAG on the off chance that they might solve the problem. Gave everything a real good clean with carb cleaner and then an light oil last night. all seems fine for the mo. Ill let you know how i get on though. EH Quote Share this post Link to post Share on other sites
Socrates75 0 Posted March 30, 2006 Put replacement ISV on today. Idle now normal and not cutting out, so I guess that was it! Now to sort erratic reverse lights :) Quote Share this post Link to post Share on other sites
dr_mat 0 Posted March 31, 2006 Don't hold your breath. One day's good behaviour might not indicate anything.. These old cars are awkward little gits, when they want to be... Quote Share this post Link to post Share on other sites
craigowl 0 Posted March 31, 2006 Possibly a good idea to replace fuel filter if it has been on for an unknown length of time? Quote Share this post Link to post Share on other sites
Socrates75 0 Posted April 3, 2006 Right... It's doing it again. At virtually every junction or stopping point. When sat in traffic the idle is unsteady and very low, keeps dipping to a point where the battery light flashes and sometimes it will catch itself and send the idle up and others it will just stall. I just don't know what to do next... I am beginnig to hate my car :( Any suggestions, apart from driving it into a wall... Which at the moment is very appealling. Cheers, Martin. Quote Share this post Link to post Share on other sites
fla 9 Posted April 4, 2006 Try moving the dashpot up a little bit - its the yellow bellows under the throttle cam which catches the cam on its way down. You need to loosen the fixing nut (8mm iirc) and unsrcew the the dashpot a few turns so it catches the cam sooner. Check it anyway by opening the throttle by hand and seeing if the dashpot damps its movement on the way down. HTH Quote Share this post Link to post Share on other sites
edd 0 Posted April 4, 2006 Give the MAF and f-ing good spray with Carb cleaner im convinced thats what sorted mine. I.e take it off and give the element a real good spray (just dont break it!!! £££££!) A few other things i did at the same time that could have resolved the issues i had (which were the same as yours) are: moved dashpot as above Cleaned and lubed ISV (as its new just give it a lube in your case) Went to clean out ISV noise damper but bust it so now its been binned and bypassed Cleaned and lubed throttle body Twisted MAF position on its longitudinal axis. Basically ensuring the connector isn't knocking against anything with the movement of the engine check all air pipes for splits Resolved my issues Hope this helps Edd Otherwise my guess is a non fully operational MAF Quote Share this post Link to post Share on other sites
Socrates75 0 Posted April 4, 2006 Cheers guys. I've booked it into Volkswerks... I'm no mechanic and this thing is really getting my goat. I don't know what is worse, the car cutting out or the continual nag from my other half about "my useless old skip". Hopefully this will spell the end of it. Martin. Quote Share this post Link to post Share on other sites