Odd stalling problem

B

Bass Ken

Low Mileage
Before I get out the schematic and multimeter, I'm wondering if someone else has experienced this same problem. My newly acquired '87 X sometimes stalls (engine cuts out immediately) when putting the shifter into reverse, and/or putting on the brakes. This is at idle, it doesn't happen over 2000 rpm. This is accompanied by the parking lights turning on without the switch being activated.

I've gone through and cleaned up all the grounds in the car which didn't help. The next step will be to trace the power through the fuse 8 and 21 circuits. TIA for any ideas!

- Ken
 
Something is wacky in the wiring. This is a first, so I'm curious to discover what is causing this problem.

Look for any previous owner installed or altered wiring that could be the source of this problem.

The EFI wiring harness is separate from the reverse/brake light wiring harness. The only place where they meet is at the fuse/relay box and even then, it's basically power only.

It is also possible some fastener or ? has impaled the wiring harness in question causing the problem. Again, look for previous owner installed items or work repair work done.

Bernice

Bass Ken said:
Before I get out the schematic and multimeter, I'm wondering if someone else has experienced this same problem. My newly acquired '87 X sometimes stalls (engine cuts out immediately) when putting the shifter into reverse, and/or putting on the brakes. This is at idle, it doesn't happen over 2000 rpm. This is accompanied by the parking lights turning on without the switch being activated.

I've gone through and cleaned up all the grounds in the car which didn't help. The next step will be to trace the power through the fuse 8 and 21 circuits. TIA for any ideas!

- Ken
Click to expand...
 
As Bernice says plus another thought...

Pull the fusing for the parking light circuit and see if the problem goes away. If NOT, then the problem is OUTSIDE the parking light circuit and causing the problem in both the ignition circuit and the parking light circuit.

If the problem does go away... the the parking light circuit is indeed CAUSING the problem in both.

In ANY case... yur gonna need your drawings and a VOM most likely...

Good luck and keep us informed...
 
I'm doubt this will help you but I had an issue where turning on lights blew the fuse. I luckily found it easily, the jack and pushed up against the side marker light causing a short. Keeping an eye out for similar "stressed" wiring as you explore might pay off.
 
Ground issue?

First check your taillight grounds, the ring terminals. If they are bad, and hitting the brakes grounds the brakes through the taillights instead (lighting them), it could cause such a large draw as to steal the needed power from the ignition, stalling the engine.

Another possibility is the taillight housings or sockets are corroded or damaged enough that power to the brake or reverse lights shorts to ground. I would normally expect a fuse to blow, check that your fuses are the proper rating. Also remove the taillight lenses and bulbs and inspect the bulb sockets and bulb bases. Check for proper bulb style even (single filament not dual filament).

The brake lights, ignition, reverse light are all powered via the ignition switch (follow the orange wire under the dash). The only thing that connects the brake lights with the reverse lights is the ignition-switched power supply and the grounding method. Mechanically they're quite separate.

Hope this helps!
 
Thanks for the tips, All. I set aside a night last week to work on this and of course that night everything worked perfectly, was not able to replicate the problem. :confuse2: All the wiring looks clean and unmolested, no bad contacts or wrong fuses that I could find. So I helped a friend with his Alfa 164 instead. We'll put some miles on the X and see if it's truly cured itself or just being difficult.

- Ken
 
You must log in or register to reply here.
Back
Top