Possible Idle Control Adjustment repair related
 

When I picked up my 82/83 euro 500 sec from the shop
I asked if they had noticed the ICV was an airslide not electroniic
They said they had noticed.
So I asked if it would be any problem
& they said it would not be.

I mentioned being concerned as the car in drive was spec 650 rpm but I thought the AC could lower the rpm with possible problems.

My mechanic told me to turn something to increase idle if it was too low.
I thought he meant the air slide valve but now I think it looks like
it could be the yellow valve with a screwdriver indentation on top?

I finally tried the Ac while driving & the 600 rpm drops to almost 500

I should call the mechanic
but obviously he thought me capablr of doing it
& I thought I knew what part he was referring to but now I;m not sure.

Would turning the circled valved increase/decrease idle?

I will have to check but since I got the car back the car is idling lower
sometimes close to 500 esp w AC

It used to idle fine in drive but after the new plugs, wires, thermal vacumn valve switch & acumulator
& possible adjustment of this circled valve
I;ll have to check its curreent position against the pics of the prior valve position & get it back to where it was.

He seemed to know that the idle of a car w a airslide valve was supposed to be higher in park at startup & he didn't mention adjusting the idle down so not sure how the work done lowered the idle.

Would I have to turn it counter clockwise to increaase rpm?
It looks like it was more 10 oclock ish & now its like 11 ish?

Thanks

I'll probably take it back when I get a chance to get it straight but in meantime I would like to know what to do if I run into a probllem...

Thanks

I would not worry which way to turn the idle adjustment screw. Simply do it by ear. I've done it this way with my 110 engine and it works fine. Then just check your tach for verification. I'm a little purplexed though by your 82?83 500 sec not having a change-over valve. My old 77 280e even has one. Aside from retarding the ignition timing for decelaration, it also INCREASES the RPM when the AC compressor is turned on. I would have to guess that your car, much newer than mine, has the same change-over valve. You might want to check into this.

Change over valve

Interesting
More things to look into...

:scream:

Thats the screw to turn though?
Don't want to mess anything up too much

Next time I;m under the hood
I'll check to see if soome one adjusted it
by memory I clocked the current position & its seems to have been adjusted...I'll go back to the original direction.

If it's on the throttle valve housing, it's the correct screw.

Not sure of that
Its right between the air slide idel control valve & cold start valve
in front of the intake...

I don't want to touch anything on the fuel distrib

I don't think he'd tell me to touch that
said something about yellow
thats
but I have the yellow dot on the aior slide valve
& the yellow vlave circled is next to that

Got it...
 

Has to be the plastic yellowed white screw....:D

That should be it.

Thanks...;)

You turn screw clockwise to slow down idle and anti-clockwise to speed up idle. Do it when engine is warm - over 175F on gauge. Should rev at about 700-750 in Park with A/C off. A little faster would be OK if you need it keep smooth idle when you put it in Drive and maybe when you use A/C .

Thanks, I'll increase idle by turning it anticlockwise in increments
to try to get a happy medium bet park & drive idle

IIdle changes so much on the car depending on its temp & if its a cold or warm start

All I know is its ideling lower now

Idle is smooth though
even at close to 500rpm w ac on so its running
just don't want to tax it & drive that low but who knows tack could be not calibrated exactly?

It's always been running hi idle in park.

Starts 1000 goes up slowly as it warms to 1500
then comes down to 1000 900 in park but was running wi spec range in drive...650ish

it has an air slide not electronic ICV which doesn't compensate as well for engine load & conditions

Truthfully I guess if someone saw it running 900 in park
they might be tempted to lower the idle
but I have been watching the idle pattern on it for 2 mo
& in drive it would come down to normal idle.
Thats why I never mentioned the high park idle to them as I didn't consider it a big problem

Maybe it should be looked into
but lowering the idle screw is not going to solve it
Something other than hi idle is working here.

I'll have to mentione\ it
as maybe that will point to whatever else is off.

Someone else mentioned that the car should have a compensation valve to deal w the AC...

I'm doing my best
its an old car
I;m not escpecting it to run like new
just like to make it as good as I reasonably can
with whatever repairs I can reasonably afford.