Engine Dies while Driving

[davidc89]

Did you have the air conditioning on?

[Jimmycxc]

Previously, I had driven about an hour and a half, stopped for a few hours, then drove back home and everything was fine. On Monday, I drove maybe 25 minutes, stopped for about an hour, then drove home and that's when it happened.

I did have the AC on.

[davidc89]

Mine will do that from time to time if I have the a/c running.

[David T]

For those who suggested checking the impulse coil, they typically fail when they get hot. For example, you start and drive normally but after about 20 minutes the engine dies and won't restart til it cools. Also seems to be very repeatable. They can fail in other ways too but that is less likely. I just had a car that was running fine and then suddenly developed a no-start. It was the connection where the wire plugs into the distributor (and the coil). Cleaned it up and now it starts every time. The way to troubleshoot is to first try to figure out if it is the fuel system or the ignition system. Two very different causes. Once you can rule out either system the possibilities narrow down considerably. The next time it dies check for spark or fuel immediately. Whichever is not present is the problem. More often than not the root problem is electrical in nature, especially if it is ignition. To do a quick check for fuel press on the air sensor plate and see if there is any back-pressure. If none, then you don't have fuel. Another quick test is a shot of Ether. If that doesn't do it you don't have spark. Or you can pull a spark plug wire and see if you have any spark while cranking. Important to do it as soon as you can after it dies while the motor is still hot.

[Jimmycxc]

So it's not an engine warming issue. I wanted to move the car to another garage that had more room. I started it up, backed up, and drove the 300 feet to the end of my street. When I pushed in the clutch to stop, so did the engine. Would not start up again. Pushed the car to my driveway, got mad, gave it full throttle as I turned the key and it fired right up. Put it back in my garage and closed the door.

I did notice that my new fuel pump was making a slightly different tune than the normal hum I've come to love when it's priming. I also realized the car shut off when there is a sudden drop in rpms, like when pushing in the clutch. I'm wondering if my pump could be acting up again, but it is a brand new pump. Will have to check the volts again.

[MML]

I'm no mechanic, but what about a collapsing rubber fuel pickup hose? Just throwing it out there.

[Bitsyncmaster]

Does your idle hold 775 RPM at normal idle?

Sounds like you have a problem with the idle circuit since it started wide open.

[David T]

I'm no mechanic, but what about a collapsing rubber fuel pickup hose? Just throwing it out there.

That is certainly a possibility but before guessing at the cause it is helpful to determine if it is a fuel or ignition problem. Also we don't know if he has the original style fuel pick-up or the newer one that wouldn't have the hose.

[Jimmycxc]

That is certainly a possibility but before guessing at the cause it is helpful to determine if it is a fuel or ignition problem. Also we don't know if he has the original style fuel pick-up or the newer one that wouldn't have the hose.

I do have the old style with the hose. Dave, do you happen to have a picture of the plug for the distributor and coil? I am on an anniversary vacation, but will be working on the car this weekend. Thanks!

[Jonathan]

I do have the old style with the hose. Dave, do you happen to have a picture of the plug for the distributor and coil? I am on an anniversary vacation, but will be working on the car this weekend. Thanks!

The wire that goes between the ignition coil and distributor is here:

http://store.delorean.com/p-6871-wire-ign-coil.aspx

I believe both ends of this wire have the same style plug. That plug is similar to the distributor end of the spark plug wires (but unlike the end that connects to the spark plug itself).

It is the red wire in this photo:

IMG_4566.jpg

The replacement coil wire may come in black, as I believe those were improved quality over the red ones.

When you push down on any of those plug end connections, at the distributor or the top of the coil, you should be able to feel it snug into place. You should not be able to lightly pull up on it from the wire and have the plug come off, it is much more firm of a connection than that. If it does come off loose, it isn't on all the way or something is out of sorts with the connection on the wire or the coil or distributor.