Help please

[VR4Kaos]

my vr4 is seems to play up sometimes if i have a play :guitarist especily if i use the tiptronic :uhoh: it happens afterwards when i start up it willl run a lil lumpy almost as if it was gonna stall but dosen't then after a few seconds resumes to normal but may i also add the revs seem a lil low on idel was wondering if this is the problem ? :uhoh:

[peter thomson]

The stepper motor probably needs a clean but a vta can cause the same thing if fitted on restart

[VR4Kaos]

whats thestepper motor and vta m8 im not a mechanic so a bit thick in this area sorry

[peter thomson]

The stepper motor controls the idle and there is a guide on cleaning it. VTA - vent to atmosphere blow off valve. Do you still have the standard one fitted

[VR4Kaos]

yes i think it standard i aint had chance do do any upgrdes yet m8

[elnevio]

Not uncommon, this. Sometimes cleaning the stepper motor doesn't cure it.

I bet it happens about half an hour after you last drove it?

[raph]

If the stepper motor looks like the typical mitsi jobbies of that era,then ive got a link :

http://www.dsmisc.com/dsmweb-dw/index.html

[WizardKing]

VTA - vent to atmosphere blow off valve. Do you still have the standard one fitted


Thanks Peter.
I had concluded that occasional lumpy idling was down to my dump-valve. It has been so intermittent, though, I wasn't certain.

Thankfully, diagnosis is a lot less hassle with a GFB hybrid valve fitted. [Setting it up with a good return-flow to sound-effect ratio was fun, too. Every set of traffic-lights saw me dive out of the car and stick an arm underneath the nearside headlamp !!]

[VR4Kaos]

Not uncommon, this. Sometimes cleaning the stepper motor doesn't cure it.

I bet it happens about half an hour after you last drove it?
yes it does how you guess

[Turbo_Steve]

Cos we've all had it! LOL

Get the idle control stepper off and clean it all out. Mine needed a touch of dremmeling off the barrel, which moved the motor away from the "dead spot", and onto another one for the same given idle.

The car learns the idle, so re-profile the motor nub a few mm, refit it, and when you first restart it'll idle very high. Leave it running and it will gradually come down.

Mine hasn't been a problem since.

[VR4Kaos]

wow all souds a bit technacal for me shall i seek a profesional to tacklethis one ?

[Eurospec]

No mate, you can do that DIY no problem.

Just take the stepper out and have a go at it. You will be fine. If you get stuck, just ask!

You remove the black inlet tube where it goes into the throttle body. You will then see the stepper sticking out of the side of the throttle body below where the intake went on. Unplug the multi plug and then remove the 2 x 8mm bolts that hold it on. Now just remove the stepper motor taking care not to lose the rubber o ring.

Clean it up as steve described and refit.

Start the car and let it idle for 10 mins or so with all electrical loads switched off, and you should be fine.

Cheers,

Ben.

[VR4Kaos]

ok will give it a try but i am scared lol

[VR4Kaos]

ive removed the inltet tube from the motor body bit cant see the stepper

[Turbo_Steve]

It's the blobby electrical piece underneath the pipe!

It's the only bit directly under that big pipe with wires going to it :)

[Turbo_Steve]

In fact, I just typrfed "Stepper Motor" into the search function, and got this:
http://www.clubvr4.com/forum/showthread.php?t=41123&highlight=stepper+motor

the stepper motor is the black bit!

Yours may not be EXCATLY the same (it changes around 1997-1998 somewhere) but they're all pretty similar.