runs for 40 minutes, then dies and will not re-start

[Farrar]

After running about about 40 minutes, the engine will not hold an idle and dies. I cannot re-start the engine until it is cold.

Any help would be greatly appreciated.

[Bitsyncmaster]

After running about about 40 minutes, the engine will not hold an idle and dies. I cannot re-start the engine until it is cold.

Any help would be greatly appreciated.

Sounds like a spark problem since it runs for so long. Could be the coil, pickup or ECU. Can you verify there is no spark after that 40 min?

[Farrar]

Sounds like a spark problem since it runs for so long. Could be the coil, pickup or ECU. Can you verify there is no spark after that 40 min?

You may be on to something there, Dave... I was using my tachometer in the engine compartment to monitor engine speed, and noticed the reading fluctuating wildly just before the engine died. The tach receives its signal from the coil's positive terminal. I will go and see if I have spark.

[DeLorean03]

Find the plug on the left side of the engine that connects to the electrical distributor. It's similar to the CSV and WUR/CPR plug - instead of blue or brown, it'll be a yellow color. Then do the following:

Straight from John's site:

This may be the problem when the car won't start until it cools down from being hot or if your car just dies and won't start for no apparent reason. Let it cool down for about 45 minuets and starts up. Should measure about 550 ohms room temp on the wire coming out of the ign distributor. When is gets hot and the car dies, there will be no ohms reading.

He is referring to the pulse coil in the electrical distributor going bad.

From this page:

http://specialtauto.com/delorean-parts/electrical.html

[Farrar]

Thanks. I confirmed plenty of spark while cranking but no start. It had been more than 45 minutes since the engine died.

I found instructions for testing a pickup coil here. If I get the chance, I'll try this tomorrow.

[DMC5180]

Thanks. I confirmed plenty of spark while cranking but no start. It had been more than 45 minutes since the engine died.

I found instructions for testing a pickup coil here. If I get the chance, I'll try this tomorrow.

Your running A Carb aren't you. Plenty of Spark but NO start. What about Fuel supply? What happens if you shoot a little Starting fluid in the Carb?

[Rad Dad]

Thanks. I confirmed plenty of spark while cranking but no start. It had been more than 45 minutes since the engine died.

I found instructions for testing a pickup coil here. If I get the chance, I'll try this tomorrow.

If you know me you know I am not mechanically inclined-- BUT after32 years of ownership, I have learned a few things and even though I am now 80, my memory is pretty goo. SO, you have perfectly described the dreaded "impulse coil" problem .. . . At least as I experienced it.

Dick Ryan, the Rad Dad

[Farrar]

Yes, I'm running a carb. The engine is getting fuel. In fact, unless I turn the key off when the engine dies, the needle valve can't hold the pressure back for very long and the carburetor floods out.

It sounds like the pickup coil might be the culprit. RockAuto has one for $14 shipped. I might as well jump on it.

[David T]

Yes, I'm running a carb. The engine is getting fuel. In fact, unless I turn the key off when the engine dies, the needle valve can't hold the pressure back for very long and the carburetor floods out.

It sounds like the pickup coil might be the culprit. RockAuto has one for $14 shipped. I might as well jump on it.

If it has spark it is NOT the impulse coil. Sounds like it is running too rich and choking on all of that fuel. Or it could be vapor lock. If the fuel going to the carb gets too hot it can turn to vapor in the fuel line or even the carb.

[Silverbullet]

Yes, I'm running a carb. The engine is getting fuel. In fact, unless I turn the key off when the engine dies, the needle valve can't hold the pressure back for very long and the carburetor floods out.

It sounds like the pickup coil might be the culprit. RockAuto has one for $14 shipped. I might as well jump on it.

Ah.... If the carb needle can't hold the fuel back... there is an issue... Did you put a in-line Fuel Pressure Regulator? If not, you should... Carbs don't need that high pressure...

Craig