1981 VW caddy high idle.

[Danny]

It idles at right around 2000rpms, I've replace the fuel filter, the lambda sensor and checked all the vacuum lines. I am seriously stumped by this. It has the CIS fuel injection.

I thought it might be the idle adjustment screw in the AFM type thing it has but the screw is stripped and I cannot adjust it. Also, I don't think its injectors because I sprayed fluid all around them and rpms didn't change at all.

Again, I'm stumped, any help?

[e30frosh]

Make that screw work for you. My 81 two door did the same.

[Danny]

wut

[kylekrueger]

if the screw is stripped and you can't adjust it then you may have to get a new fuel distributor. I would try and make the screw work.

[Massive Lee]

Damn K-Jetronic. CIS is very sensitive to adjustments. You may want to look for a proper crew, and get a looooooooooong allen key.

[.cj.]

What kind of condition is the intake boot and throttle body boot in?

Is the meter moving freely?

BTW, the allen is a 3mm and as Lee stated, it needs to be long.

[der affe]

i forgot to tell you about the air flow meter plate. take the boot off and look at the level of it. it should sit level with the narrow part of the taper in the cone. if it is high or low, bend the spring steel clip to make it sit level when the car is off. over time the clip gets bent from it slamming down on it.

also you will probably need to mess with the adjustment screw. you need to look for a BAP/GEON if you can find one in your town (i know that they were in san deigo still years ago) they carry the EMPI brand parts and you can get the t handle allen for around $15 from them. otherwise look on TECHTONICS TUNING's Web site and order one from them ( i think they were the cheapest shop to order them from)

also remember you need to make your adjustment, then rev it and let the air flow plate settle. DO NOT rev it with the allen in the screw as it will change the adjustment.

they also make a CIS specific injecter cleaner. i think it is called Jetronic, it is made by LURBOMOLY. Napa carries it so you should have no problem finding it. i don't know what is so specific about it, but it works really well at breaking up deposits in the fuel distrubtion blocks. they have VERY small passages that pulg easily if the car sat for any length of time.

i don't remember if those cars had an idle air motor, but on the early A-2 cars, the boot that they popped into was prone to tearing and creating leaks.

if you can't get the screw to work for you, and have trouble finding a replacement air flow meter (minus the fuel distubutor) i can see if i can come up with 1 from my friends shop at a decent price.

[Danny]

Yeah look for one for me please, Greg. I've also been reading about the AAR.

[Massive Lee]

Minimum length. I had a Hazet and it was three times as long.

[Danny]

Also I tried the idle screw and it does nothing, but when I pushed down on it the idle went down until I let up on the screw, then it picked back up.

[MonkeyMadness]

Did you check the throttle cable?

[Danny]

Yes throttle cable is fine. All the intake boots are new.

[MonkeyMadness]

Spray carb cleaner around the base of the intake manifold.. you may have a leak?

[Danny]

No easily visible vacuum leaks, as stated in the OP.

[Ryann]

Quit messing with the screw. That's the idle mixture screw. The only way to properly tweak idle speed on a CIS VW is to adjust the throttle stop at the throttle body. You probably either have an auxiliary air valve that is stuck open (it's the cone shaped thing at the rear of the intake manifold that allows air to bypass the throttle plates) or burnt/shrunken injector cups/seals.

If, however, you're dead set on fucking up your idle mixture give me your address and I'll mail you the official Bosch CIS idle mixture adjusting tool.