Narrowed down intermittent no-start, help please

[2ndwind]

Hi Folks, '82 FI
I've had an intermittent no-start problem since I bought this car three years ago. It used to just click. I put in the recommended starter relay and it has been cranking over every time for a year. However, occasionally, it will not fire off. This even happened at the mechanic's shop. We cranked the engine many times with breaks in between. The only thing they could find was no power to the (aftermarket) electronic ignition and coil. While investigating, and periodically cranking, it suddenly started. I left it there for 2 days. They could not duplicate the problem even after seeing it happen. Wiggling and pulling on wires did not make the problem reappear.

Recently I noticed that when it does not start, the brake warning light and seat belt light at the center panel have not lit during cranking. If I wait a few seconds with the key in on position, I hear a click somewhere and the warning lights come on, then it fires right up and the warning lights go off. Works repeatedly afterwards. Then suddenly does it again. What is going on here?

Only once has another thing happened (probably unrelated). When the car was cold and idling very low, each time I put it into reverse with the clutch pushed to the floor, it killed it immediately, no elec. power, clutch not released AT ALL. After the third time, I revved the engine before putting it into reverse and it didn't kill it. Hasn't repeated this since. I can only think shifting into reverse somehow shorted something (reverse lights?) killing the engine. But nothing similar since.

Thanks in advance for any insight.

[vandor]

My guess would be that the ignition switch is intermittently not energizing one of the circuits.

[divace73]

My guess would be that the ignition switch is intermittently not energizing one of the circuits.

I'd second that..

[maytag]

My guess would be that the ignition switch is intermittently not energizing one of the circuits.

I'd second that..

yeah, me too.
As for confirming that, I'd recommend you check the wiring connections on the back of the switch. cross your fingers you find something making a poor connection and you fix the problem. and then (while it is working correctly) put a test-light on it and map it out.
Next time the issue occurs, put your test light back on it and see if it still maps out the same.

These switches are now OLD (if original equipment) and are quite prone to failure.

[2ndwind]

Thanks Guys,

My suspicions exactly. Maytag, I have checked, FOUND, and fixed poor connections behind the ignition in the past. I will map it out as you say and keep my tester with me when out.

I am aware that the new switches are both, cheap and poor reproductions. I guess I'll have to try a used one until it fails. I'll also look for the rebuild instructions I saw on here a while back.

[spider2081]

Power for the ignition switch originates at the alternator output terminal. The smaller wire on the alternator output connects directly to fuse 10. This end of Fuse 10 is jumped at the fuse block to fuse 9. Fuse 9 has 2 black wires coming off of it. Note these connections are not the fused side of the fuses but the unprotected side of the fuses. One of those black wires feeds C31 the ignition switch terminal 30-1. When the ignition switch is in the run or start position the switch connects ignition switch terminals 30-1 to 15-64 or the black wire to the pink wire at the ignition switch connector. The pink wire powers the warning lights and the ignition. I think the connector behind the ignition switch is the most common cause of your problem. How ever I would certainly check the connections on fuses 9 and 10 and the connections on the alternator output terminal.