High Idle RPM

[Chop 'N' Join]

Hi

I have a 380SEC - 1983 UK Version.

It is revving at about 1000-1100RPM.

The Idle Control Valve is working.
Removed plug, engine speed increased to 1500RPM.
Tested by supplying 12V, engine speed dropped and cut out.

Tested the temperature control valve by bridging the plug terminals, that's working.

Connected a clamped pipe in place of the Idle Control Valve and the engine speed dropped to 700-750RPM.

So, I think it is the Control Unit (Electronic Idle Speed Control).

I need to remove the Idle control unit.

Where is it located?

Can you give me any details as to removal?

How long does it take?

Thank you for any help you can give.

 

[television]

If you have an auxillary air valve make sure it is closed, and that there no vacuam leaks.
You have a throtle posistion swich mounted on the throtle cable, that that tells the main computer that the engine is at idle and siganls the idle relay/ computer to work, the idle control relay signals the idle control valve the correct RPM for idle, if the idle relay is not working, the fail safe is to have a very high idle.

On the 560sel its mounted the relay is mounted in passenger compartment on the fire wall behind a cover, could be the same on yours, most of the faults are bad soldered joints on the relay.

Hope this helps a little. Malcolm

 

[Chop 'N' Join]

Hi Malcolm

Thank you for your help.

There doesn't appear to be any vacuum leaks.

Where exactly is the throttle position switch?

What sort of RPM the fail safe high idle?

I checked the passenger compartment, not there.

Any other ideas?

Can the Control Unit (Electronic Idle Speed Control) be reconditioned or repaired?

 

[Chop 'N' Join]

Hi Malcolm

OK.

Found the location.

You need to be a trapeze artist or contortionist to get to them!

Located TWO UNITS next to steering column, above pedals.

One is black plastic case about the size of a cigarette pack, with small plug.

The other is larger and silver metal case.

Which one is it?

Thank you for your help.

 

[television]

I cant remember when changes took place, but on early cars there are double distributor points, the bottom set trigger the idle relay, on later cars there is a switch on the throtle cable.
the fail safe speed is 1100 RPM

you will get some more info here,use your VIN number and find your car.

http://www.detali.ru/cat/oem_mb0.asp?TP=1


Malcolm

 

[Chop 'N' Join]

Hi Malcolm

Finally got the thing off.

The the head of the screw retaining it to the bracket was impossible to get to.

I will replace it with a nut, bolt and washer set-up when I refit.

Well, I have just got to get it repaired now.

Thank you for all your help

 

[Chop 'N' Join]

Hi Malcolm

The unit I have is a 002 545 07 32.

I saw in one of the threads that you can test and repair these units.

Would you be interested in repairing mine?

 

[television]

Hi Malcolm

The unit I have is a 002 545 07 32.

I saw in one of the threads that you can test and repair these units.

Would you be interested in repairing mine?

I can test 98% of the bits inside, the two eproms I cant check as I do not have the dump code. Email me m.watford@homecall.co.uk for address

Malcolm