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Posted by: oakdalecurtis Mar 5 2017, 05:47 AM

76 2.0, 120k miles, all stock engine parts except for Crane Ignition. Engine runs on after shutdown for 3 to 5 seconds. All engine parts working, thermostat, aux air regulator, no vacuum leaks, motor runs beautifully and pulls hard, engine idles after warmup at about 600 rpm. I tried adding a diode to the lead from the alternator to the generator light, that made no difference to stopping the run on after shutdown. Any other ideas to suggest that might fix it? (besides popping the clutch to stop the engine)

Posted by: rgalla9146 Mar 5 2017, 07:38 AM

timing too advanced ?

Posted by: Shadowfax Mar 5 2017, 08:18 AM

Would running higher octane gas help?

Posted by: bretth Mar 5 2017, 09:36 AM

Did you change your tail lights recently? Using a single filament bulb instead of the correct dual filament can make the engine continue to run.

Edit - Never mind I just reread your post it only runs for '3 to 5 seconds'. I don't think the tail lights would affect this.

Posted by: The Cabinetmaker Mar 5 2017, 10:32 AM

I second timing.

Posted by: oakdalecurtis Mar 5 2017, 11:00 AM

I removed the dizzy recently to install new trigger points. I did not loosen the adjustment bolt, only removed the hold down bolt to get the distributor out. But that may have altered the timing slightly non the less. I am taking the car in to a very good mechanic next week for it's required smog check, so I will ask him to check the timing before running it for smog. Thank you for your suggested solution.

Posted by: Krieger Mar 5 2017, 11:12 AM

Ignition switch.

Posted by: stugray Mar 5 2017, 12:03 PM

I disagree with the timing being the culprit.

If the ignition is OFF then the "sparks" should not be firing and it wouldn't matter where the timing is set.

Another thing that can cause run-on (other than an electrical problem) is if the heads are way too hot.
Do you have a temp sensor to tell you if the engine gets hot?
Does it run-on after a very brief startup or only after a long drive?

Posted by: type2man Mar 5 2017, 12:59 PM

I think I read something here a while back about the same issue and it turned out to be the Crane ignition.

Posted by: oakdalecurtis Mar 5 2017, 01:18 PM

It runs on even after short drives. The temp outside has been cool and I don't think the engine is running hot. Since I removed the rain tray the engine has been running cooler than ever. The cylinder and oil temps seem fine. Will check timing before smog check and go from there.

Posted by: Dave_Darling Mar 5 2017, 02:19 PM

Injected, right? In theory, all fuel should cut off instantly when the key is turned off. That means no run-on from ignition or hot-spots. You need fuel for run-on.

So, either you have a lot of fuel loaded up in the intake, or your FI is continuing to add fuel.

I would suspect the ignition switch. Or maybe something else is feeding back into the ignition circuit?

You'll want to isolate the problem. See if unplugging the trigger points or the four-pin plug at the relay board kills the engine. If so, you've got something continuing to power the fuel injection.

--DD

Posted by: oakdalecurtis Mar 5 2017, 08:10 PM

QUOTE(Dave_Darling @ Mar 5 2017, 12:19 PM)

Posted by: oakdalecurtis Mar 7 2017, 03:36 PM

Here's relay board, pull what?

Posted by: Dave_Darling Mar 7 2017, 03:51 PM

Bottom-right on your photo. (Left-rear as it shows in the car.) Four pins, white wires.

--DD