89 m20 low idle please help

[Eightynine]

Car runs great after 800rpm
Has a deutche rennsport chip (might be problem)
Sits at like 600 and makes my charging system struggle
Iv replaced everything except icv my engine bay is clean everything is hooked up tight as far as hoses go. Willl take off like a bat out of he'll in overdrive and I'm running a auto tranny
Idle is higher I'm park but drops down 200rpm ish in reverse and drive.

Is there something I'm missing . Car runs great like other m20's I've driven but idle is too low

[e30Villain]

You might need to adjust your ICV.

[Eightynine]

It's the T shaped kind of icv. Also icv vibrates with ignition on. I think only the L shaped icv is adjustable ?

[e30Villain]

It's the T shaped kind of icv. Also icv vibrates with ignition on. I think only the L shaped icv is adjustable ?

Not sure if late model ICV's are adjustable.Pull it out and start shaking it, if you hear clicking then that means your ICV is clean. If you don't hear it then I'd suggest picking up some carb cleaner and see if that helps you out. Thats what i did for my early model and worked wonders on the idle.

[Eightynine]

Parts inside move freely when I hold it upright and give it shake /twist

[TurboJake]

Whenever my M20 has a low idle I just hit it with a hammer and it always comes back up.

I wouldn't recommend this route... And no, I'm actually not joking. But in all seriousness, 9 times out of 10 it's vacuum leaks for these M20s. Dropping of the RPMs while in drive or reverse is normal. You're putting the engine under a slight load, but that is a bit low.

[Thizzelle]

Car runs great after 800rpm
Has a deutche rennsport chip (might be problem)
Sits at like 600 and makes my charging system struggle
Iv replaced everything except icv my engine bay is clean everything is hooked up tight as far as hoses go. Willl take off like a bat out of he'll in overdrive and I'm running a auto tranny
Idle is higher I'm park but drops down 200rpm ish in reverse and drive.

Is there something I'm missing . Car runs great like other m20's I've driven but idle is too low

happens with mine. it drops when you put in gear. Also I took to smog shop and asked what the idle was it was perfect at 750. I must have bumped the needle on cluster when out because it reads 600. Thought my engine was fucked for months. I would recommend to get the rpms read from some shop or what not.

[Eightynine]

Ok I also thought Maybe the needle wasn't accurate. I'm trying to raise my idle because my volt meter shoots to 13.5+ after rpms hit 750 ish below that my alternator struggles with fan and lights on.
If it wasn't for my low charging problem I'd let it stumble at 500 rpm and not even worry a bit. My engines high mileage at 200,000 with broken odometer gears :) drives smooth though gets up to 100mph easily with only a slight rumble

[Eightynine]

I thought vac leaks caused hesitation and high idle I have neither.

My other car is a 1965 dodge polara the idle is adjusted with a screw thank god. The good old days yeah they're gone

[Thizzelle]

vac leaks create high idle, engine stall (had GF call me and say her car keeps dying at stop signs after she put oil in it, Me: check to see if you put oil cap back on. her: O that fixed it, thanks babe) or stumbles not a consistent low idle.

[Eightynine]

My idle seems low but it's smooth like shaft, never had it stall out ever. Will a alternator belt that's not tight enough cause low charge? I'm stumped I changed my voltage reulgator with a pen German part and now my car charges at idle with no lights or fan but turn on the ac, fan and lights and my alternator goes below.

[TurboJake]

My engines high mileage at 200,000 with broken odometer gears :) drives smooth though gets up to 100mph easily with only a slight rumble

That engine is still a baby...

vac leaks create high idle, engine stall (had GF call me and say her car keeps dying at stop signs after she put oil in it, Me: check to see if you put oil cap back on. her: O that fixed it, thanks babe) or stumbles not a consistent low idle.

Yes they can. It's going to be a very small leak, and a pain in the ass to pinpoint without a smoke test.

[Thizzelle]

check the voltage regulator in the back of the alternator it might need replacing.
http://www.pelicanparts.com/catalog/..._pg1.htm#item0

[Eightynine]

Well iv been driving it for like 5 years it's been around. But compared to my bullet proof vintage steel yes it's a baby.

[TurboJake]

\/ 513k, unopened, and still a baby engine wrapped with a shitty winter driven body \/ M20's are tanks.