Engine fires, runs, then quits immediately

[David T]

If you can keep it running but it runs badly, either you have bad, dirty injectors or the mixture is way off. Check the flow patterns on the injectors and if they look OK tweak the mixture screw a little richer.

[Ron]

Ron, the CSV washer I was talking about was a copper washer that was laying flat on the bottom of the intake under the brass pipe and the long screw went through it. Made no sense and didn't see it in the parts book.

Maybe I'm not following you... There needs to be a seal there. (I've seen copper and rubber there.) Its #9 in the link I gave you above.

Hi Ron,

In RUN, I am getting +12V to white/yellow at the coil but only if I remove the wire from the dual spade (which is shared with a noise suppressor yellow wire) and test it by itself. But then, if I plug the white/yellow wire back into the coil (key still in RUN), and I measure the coil terminal that I just plugged it into, I am getting 5.8V. Does that sound right?

In RUN, power (12V) has to go through 2 resistors in the block. While cranking, it goes through one resistor. So, there shouldn't be 12V on the white/yellow at any time.
ResistorConnections-3.jpg

So I was just reading this thread -

http://dmctalk.org/showthread.php?12...uestions/page2

In it, Dave M says white/yellow should go to + terminal on Accel coils. Mine has been wired up opposite that for probably 15 years. Is that a thing? I've never had ignition problems until now so I'm not sure I should swap it....

Swap it!

[Helirich]

If you can keep it running but it runs badly, either you have bad, dirty injectors or the mixture is way off. Check the flow patterns on the injectors and if they look OK tweak the mixture screw a little richer.

This would be my guess. It doesnt take much on that screw to make it run like crap.

[82DMC12]

Hi Ron,

OK I'll try to explain better.

For the CSV, I have, in order, Bolt head, washer, brass pipe, o-ring, manifold. Just like it shows in the parts diagram https://store.delorean.com/parts/fue...me-switch.html

What I found on disassembly, laying in the hole in the manifold that the CSV sprays into, in the casing, there was a copper washer on the floor of the port in there, which the screw ran through and then threaded into the manifold. But that makes no sense to me because the bolt does not need to be sealed there and there is no force downward onto the washer. So I think it was someone's mistake in the past. The washer is not found in the parts book for either the link above or the Induction system page. Does that make better sense?

Regarding the ignition coil, I will definitely do some continuity checks tonight but here is what I have -

• + side of the coil has a white (maybe it's white/slate) wire going to it and that's it
• - side of the coil has a white/yellow wire going to it as well as a noise suppressor mounted on the firewall. These two wires are connected on a piggy back connector and then pushed onto the coil spade.
• If I remove the white/yellow wire from the piggyback terminal and test it alone with a meter (stick a probe into the wire connector) I am getting 12V with the key in RUN position (red probe on wire, black probe on engine)
• If I put the wire back onto the terminal and then test the terminal itself, I get just under 6V with the key in the RUN position (red probe on terminal, black probe on engine)

How can the voltage drop just because the wire is plugged into the coil? I have not tried to check the voltage during cranking yet.

I'm trying to read your diagram. I'm using this one but it doesn't have the relay in it.

coil circuit.jpg

Looking at this diagram, all the wires look correct with the exception of my coil terminals are apparently reversed and I have two white wires going to the top right ballast resistor terminal.

Looking at your diagram, is the flag-looking thing on the bottom supposed to be the coil? If so, it seems to show UY going to one side of the coil, and a WY+ W going to the other side? Am I reading this right?

Could I have a problem with the ballast resistor relay? I have a number of relays laying around if I know what type I can swap it with.

A lot of people think these Super Stock coils are trouble. How can I test it with my meter?

Maybe I should switch back to a standard Bosch coil like this one
https://www.rockauto.com/en/moreinfo...t=7060&jsn=302

Additional photos for reference -

PXL_20220111_133013089.jpg
PXL_20220111_133024702.jpg

[82DMC12]

This would be my guess. It doesnt take much on that screw to make it run like crap.

I am going to get some more mason jars and go through this process again once I rule out ignition coil/ ballast

[Helirich]

I am going to get some more mason jars and go through this process again once I rule out ignition coil/ ballast

The mason jars test is to check balance across the injectors. It’s a good idea and I need to do it, but in your case, just pulling one injector and making sure it is spraying the minute you push the plate down might be the answer.

[82DMC12]

The mason jars test is to check balance across the injectors. It’s a good idea and I need to do it, but in your case, just pulling one injector and making sure it is spraying the minute you push the plate down might be the answer.

Good point. I literally just checked flow with six jars in like, September, so I'm sure it all has to be good in terms of pattern and volume. Even if it wasn't, it would still run, just crappy. I can't even get it to idle right now.

Am I correct in that I can get a baseline CO by pulling an injector, placing it in a jar, jump the RPM relay, then check for spray. Turn the CO screw clockwise (richer) until I get a spray, then back off until it just stops? I already know I'm not flooding because I had all six injectors out when reinstalling the whole fuel injection and I did do a quick RPM relay jump to make sure I was leak-free before putting the injectors back into the ports.

[Ron]

Hi Ron,

OK I'll try to explain better.

For the CSV, I have, in order, Bolt head, washer, brass pipe, o-ring, manifold. Just like it shows in the parts diagram https://store.delorean.com/parts/fue...me-switch.html

What I found on disassembly, laying in the hole in the manifold that the CSV sprays into, in the casing, there was a copper washer on the floor of the port in there, which the screw ran through and then threaded into the manifold. But that makes no sense to me because the bolt does not need to be sealed there and there is no force downward onto the washer. So I think it was someone's mistake in the past. The washer is not found in the parts book for either the link above or the Induction system page. Does that make better sense?

Regarding the ignition coil, I will definitely do some continuity checks tonight but here is what I have -

• + side of the coil has a white (maybe it's white/slate) wire going to it and that's it
• - side of the coil has a white/yellow wire going to it as well as a noise suppressor mounted on the firewall. These two wires are connected on a piggy back connector and then pushed onto the coil spade.
• If I remove the white/yellow wire from the piggyback terminal and test it alone with a meter (stick a probe into the wire connector) I am getting 12V with the key in RUN position (red probe on wire, black probe on engine)
• If I put the wire back onto the terminal and then test the terminal itself, I get just under 6V with the key in the RUN position (red probe on terminal, black probe on engine)

How can the voltage drop just because the wire is plugged into the coil? I have not tried to check the voltage during cranking yet.

I'm trying to read your diagram. I'm using this one but it doesn't have the relay in it.



Looking at this diagram, all the wires look correct with the exception of my coil terminals are apparently reversed and I have two white wires going to the top right ballast resistor terminal.

Looking at your diagram, is the flag-looking thing on the bottom supposed to be the coil? If so, it seems to show UY going to one side of the coil, and a WY+ W going to the other side? Am I reading this right?

Could I have a problem with the ballast resistor relay? I have a number of relays laying around if I know what type I can swap it with.

A lot of people think these Super Stock coils are trouble. How can I test it with my meter?

Maybe I should switch back to a standard Bosch coil like this one
https://www.rockauto.com/en/moreinfo...t=7060&jsn=302

Yes, clearer...I was not getting you had an o-ring AND and the "extra" copper washer between the pipe and manifold.

The flag looking thing is the wire harness (each wire is labeled where it goes to...).

The voltage can (will) drop when the wire is connected to the coil because the coil is a load (resistor)...
The White wire from the aux. solenoid brings 12v to the resistor block. In RUN it goes through 2 resistors, reducing the voltage "a lot". In START, the relay bypasses one resistor, reducing the voltage "a little". (This is just for hotter spark during cranking...and to keep the coil from overheating etc.)
You do not want anything but the white/slate wire connected to the (-) side of the coil, because anything else will interfere with the ignition signal.

From manual, with relay:
Image2.jpg

[82DMC12]

Yes, clearer...I was not getting you had an o-ring AND and the "extra" copper washer between the pipe and manifold.

The flag looking thing is the wire harness (each wire is labeled where it goes to...).

The voltage can (will) drop when the wire is connected to the coil because the coil is a load (resistor)...
The White wire from the aux. solenoid brings 12v to the resistor block. In RUN it goes through 2 resistors, reducing the voltage "a lot". In START, the relay bypasses one resistor, reducing the voltage "a little". (This is just for hotter spark during cranking...and to keep the coil from overheating etc.)
You do not want anything but the white/slate wire connected to the (-) side of the coil, because anything else will interfere with the ignition signal.

From manual, with relay:
Image2.jpg

OK so it sounds like my meter readings are normal then. I think the best thing to do next is to try to test the coil to make sure it's not burned out or something (how do I do that?), reverse the wiring on it so it's correct, and then do a CO check.

[Ron]

OK so it sounds like my meter readings are normal then. I think the best thing to do next is to try to test the coil to make sure it's not burned out or something (how do I do that?), reverse the wiring on it so it's correct, and then do a CO check.

...except you shouldn't be showing 12V on the white/yellow wire, ever. You can put 12V on the coil (+) as a test, but don't leave it that way...