Re: [DML] no start problem

[DMCVegas@xxxx]

If your having a problem with the Idle Speed Circuit, there is one 
easy way to find out. Hold the gas pedal about ½ way down, and start 
the car. The engine should fire up. But when you take your foot off 
the pedal, the RPM's fall at a normal rate. Only now they will drop 
down to 0 and kill the engine.

It sounds to me like you have a bad ground connection. I did have a 
problem with a wire that went bad in the circuit. But I don't think 
you are having the same problem that I did. You said before that you 
grounded the connection, and everything worked ok after that. So this 
sounds like you had the problem already diagnosed/cured. I am curious 
though as to where you grounded the connection at (I'll explaine why).

Now, there is one more thing. The microswith doesn't just turn the 
Idle Speed Circuit on. It also activates a small solenoid on the back 
of the engine. That's why there is an inline diode to prevent 
feedback (section D:05:02). What is tied into this circuit is a 
vaccum solenoid. The EXACT operation of this solenoid and it purpose, 
I'm honestly not 100% sure. I think that it kills that vaccum 
connection between the distributor, and the thermal switch to prevent 
enrichment of the fuel durring idle. In other words it kills the 
vaccum to the Control Pressure Regulator. Although the lines do also 
conect up to the engine. But since it is tied in a way to both your 
problems (vaccum/engine performance & idle speed electrical 
connection), it is something that you will want to investigate. I 
would reccomend that you first call your friendly DeLorean vendor for 
a complete explanation of the circuit, as well as a diagnosis. 
Perhaps the 2-prong connection on the back is dirty, and just needs 
to be cleaned.

I hope this helps you track down your problem by shedding a little 
more light on the subject w/a differant angle on things.

-Robert
vin 6585