gronkX

I have an '86.5 5-speed, which I have owned for close to 20 years. Car has about 140,000 miles on it. I'm the 2nd owner, but if I can't figure out how to get it running reliably it might soon have a 3rd owner


Symptoms: Car will start and run fine, sometimes for a couple weeks, then it just dies. It might not start for an hour or a week, but if I do nothing at some point it will start running again. After a few rides on a tow truck, I would really like to get this problem fixed this year.

What I've done over the last two year:

- I have cleaned all of the grounds, even the ones in the V of engine. A couple of these looked questionable, so were fixed.

- all the '53 relays are new, and I have checked each of them in the horn position to verify that they're good.

- the CPS was replaced

- all ignition wires, distributors and rotors were replaced

- at one point, my mechanic found a short in one of the fuel injector connectors. When it was shorted, the car would not start - when it wasn't, it would start fine. I was hopeful that we had the problem fixed, but a couple weeks later it was doing the same thing again.


Now, I just tried starting if for the first time this year, and it won't start at all now. It cranks fine though.

- when I turn the key on, I sometimes (but not always) hear the fuel pump running. When I jump the fuel pump relay, it still won't start.

- I checked the voltage going to the ECU - I was seeing 12v across pins 12 and 25 of the ECU connector when the ignition was on

- I put a timing light on one of the spark plug wires, and was not seeing any spark when the engine was cranking.

- I don't have a scope, so I can't verify that the CPS is actually working, but I cut off the end of an old one and verified that the continuity is good between the female connector and pins 7, 19 and 20 of the ECU connector. I'm assuming that the CPS isn't the problem since I have replaced it with a new one and an still seeing the problem.


So, what else can I look at?

bureau13

Well I was having what sounds like the identical problem, and it turned out to be the "extra" wire coming connected to the positive battery terminal. Apparently that runs the fuel pump...it was loose and a little bit oxidized, so sometimes the fuel pump got power, and sometimes it didn't. That would not explain your lack of spark, however...

Barry Chan

Ignition switch, Fuel pump fuse changed? I had intermittent no start and it was the fuse, hope its something simple.

gronkX

I checked the #42 fuse (it's good), cleaned off the connections on smaller wire going to the positive terminal, but there's no difference. Because the fuel pump runs when the relay is jumped, I don't think that's the problem, but at this point I'll try pretty much anything.

M. Requin

What was done to correct the FI wiring problem?

gronkX

Is a way to test the ignition switch? There was an alarm installed in the car at one point. There's a small yellow wire coming off the ignition switch that has been cut & spliced, but the car does still crank & all of the interior lights work when I turn on the ignition.

gronkX

He replaced the connector & boot, wired it into the harness a couple of inches back. The original problem he found was inside the boot.

depami

Did he do just one, or all of them?

If just one, the others could have same problem but that wouldn't explain no spark.

worf928

This! X 10.

If another bad injector line found, a new or good-used injection harness might be the ticket here.

gronkX

Just one of them, but when the injector was shorting out, the engine would not run - I don't know if there was spark or not, but that could explain the problem.

gronkX

I'm thinking a new injector harness is probably the next step - the problem is finding one. I know Carl sells rebuilds, but at this point spending $2k+ on a guess isn't in the budget, so I'd need to find a good quality used one.

depami

I have a used one but I wouldn't say it's good quality.

I am in the process of replacing it for issues similar to yours. I was chasing my tail between no spark and no fuel.

I was extremely lucky to score a new one for $400 something.

gronkX

I don't suppose there's another one available from the same source?

What do you want for the used one?

depami

I got the new one off ebay.

My old one is hard and brittle. All the ends would need to be replaced. It is likely no better than the one you have.

Check >>> this <<< out.

gronkX

I've been thinking of attempting a rebuild, and having a donor would mean I don't need to pull mine out first.