1981 VW caddy high idle.

[Ryann]

How far down is the plate supposed to drop? It sits right at the bottom of the cone but if I push on it it goes down farther.

Don't push down on it. Right at the bottom of the cone is good. But what's the PLUNGER doing?

[Danny]

I am not sure. But I have found there is no idle adjuster at all, its gone. I can see right through the hole where it should be. Think that's my issue?

[Danny]

Although everything does move very smoothly.

[Ryann]

I am not sure. But I have found there is no idle adjuster at all, its gone. I can see right through the hole where it should be. Think that's my issue?

The idle mixture adjuster in the injection control unit or the idle speed adjustment screw on the throttle body?

If the plunger is gummy and hanging up inside the distributor or some asshole fucked with/lost the idle mixture screw in the injection unit it's possible that they compensated for it by messing with the idle adjuster screw at the throttle body. If you look at the diagram I just put up you'll see that the idle mixture adjustment just plays with the relationship between the airflow arm and the plunger. This does not affect idle speed directly so much as a/f mixture at any given idle speed.

[Danny]

There is no mixture screw in the AFMtypething with the fuel distribution block. Should I even bother putting the one with the missing mixture screw back in or just go grab one with one?

Where is the idle adjustment on the throttle body?

[Ryann]

IIRC the TB idle adjuster is on the back facing the firewall, and may be "tamper proof". By the way, we're assuming here that your throttle plates are in the fully closed position at idle.

[Danny]

Should I even bother putting the fuel distributor/afm thing back in or should I just go pick up a new one?

[Ryann]

Should I even bother putting the fuel distributor/afm thing back in or should I just go pick up a new one?

Good point. Someone's obviously been tampering with it. You could at least obtain a new idle mixture screw from a second hand unit. Then again yours is probably laying in the bottom of the air box somewhere.

[Danny]

No its not, I'll just have to take a trip to the junkyard tomorrow and see what I can find.

[lennon]

Not trying to threadjack, sorry, seems like some people with some CIS knowledge in this thread. I'm working on a Mercedes 560SL at work, anyone know where to get a new fuel distributor diaphragm?

[ansonivan]

Have you located the idle screw on the throttle body yet? I've seen two types: one has a hex head which protrudes from the throttle body, the other uses a flat head screw driver slot and is flush or sunk into the throttle body.

Checked ignition timing? That can cause a high idle as well.

[Danny]

Okay this CIS injection is kicking my ass, any thoughts on doing a carb conversion? I've found kits online to the tune of about 400 bucks.

[OrganicMechanic]

spend it--

[Danny]

Any other insight?

[der affe]

BAM!!!!!

http://badger-5.com/

http://badger-5.com/2001/throttlebodiesdth.html

carbs are a bitch to get all around power from and suck gas like a fat girl on coolwhip.

it can be done, but you wont be entirely happy with the results. also cali will frown on it.

how did the other throttle plate work out?