Korwen

As the title says, my 1982 5-speed isn't starting.

What it's doing is when I try to start it, it sounds like it's going to start, the engine rumbles a little bit, and then dies.

I haven't driven the car in about 3-4 weeks, and last time I drove it I put some gas in it.

The past year or so whenever I've tried to drive the car without having driven it for a couple weeks it would do this for 5 or so times and then fire up, so it has a history of doing this and being hard starting, but the past week i've tried starting it for 30 or so minutes about 3 times, and I've conceded to the fact that something's wrong.

So far I've jumped the fuel pump relay and verified that it's not the issue, and it wasn't. Fuel pump got power when I jumped it, but car didn't start. I've tried hooking the battery up to my beater with some jumper cables in case it didn't have enough juice to kick the car over hard enough, but that didn't work either.

My next steps are going to be to pull a plug tonight and verify it's getting spark, and maybe get some fresh fuel with some seafoam in it into the car on the off chance that the fuel in it has gone south. After that, I'm out of ideas. If it gets spark, and is turning over enough to get the engine almost started I can't help but think it's a fuel issue. If the fuel pump is running, that doesn't mean my injectors are working. How can I diagnose that I'm actually getting fuel in the cylinder, and what are the next steps after this?

I know this is all a result of me talking about selling her. I say "Ebay" once in earshot and all of a sudden she's not starting. Damn sensitive cars.

ThomO

You could try some starting fluid in the through the airbox to see if it is a fuel issue.

I would also check to make sure you are getting spark like you said.

Could be a bad thermo-time sensor that is not allow it to start when cold. There is a simple test for resistance in the WSM to verify.

Good luck with a fix.

Landseer

I'd clean the two ground wires that attach to the passenger cam cover. Its a bit of a project, as at least one is hidden at the top of the "o" in Porsche by the air pump emissions valve and piping. That must be removed first. These represent the grounds for the injector harness and both computers and O2 sensor, believe it or not. I've cleaned-up starting behavior and eliminated random missing by polishing them.

Depending on results, I might then jumper the injector relay XVI using a three-sided jumper, 30 to 87 to 87a (looking at relay for the reference diagram so you know which terminals are which). This takes control voltage out of the equation. And these relays are known to fail on one side. Despite the wiring diagrams, both halves of the XVI relay must engage, else its a no-start. I've had them fail intermittently.

I'd also remove and clean the rotor edge and carefull without scratching cap, the 8 cap electrodes inside.

karl ruiter

If no spark, I would look at the famious green wire coming out of the distributor. If you do have spark, you can buy a 'noid' light that plugs in to the injector connection and lights up when the injector fires.

Landseer

That noid light is a real useful tool.

The green wire is interesting, too, but I'm careful not to mess with the ends, due to fragility, unless I can see some cracking or degradation already beginning, else rest of troubleshooting doesn't work. So its a first place to inspect, but don't start messing with it unless you are committed to replacing it. If its not working right, you won't have spark nor noid light actuation at injectors.

Lisle makes a nice little light, very worth the money, but a 12V bulb can be made to work.

Maleficio

Landseer's right about the grounds.

Your symptoms are exactly what I recently dealt with on my 82.

The ground terminal for the L-Jet computer which fires the injectors is mounted under the air valve Landseer mentioned, it's on the passenger side valve cover. The air valve hides the terminal. The screw which secures the air valve to the valve cover had worked it's way loose, and the grond terminal stopped making contact to ground, so I had no injector pulsing.

I relocated that ground to another spot that's visible and easily accessed. I also added other grounds. I kind of made a ground network crossing the engine and mounting on the other valve cover. I do not want to ever deal with a ground problem again for the injection system. The new grounds are the blue wires in the photo. I added one to the distributor, and that one really smoothed out the running.

Check out my process of madness before I finally found the problem:

http://forums.pelicanparts.com/porsc...hose-guys.html
http://forums.pelicanparts.com/porsc...y-new-pic.html

James Bailey

He said it "rumbles" I assume that means it fires and runs sputters briefly.....if that is so then it has spark ! Perhaps it is firing on the cold start injector BUT the injection brain is not injecting..... Injection relay might be weak.

cpayne

After grounds if problem doesn't go away. You can also turn the ignition on and off x3 without trying to start it. Then on the fourth try see if she fires.
Works on my 81

Maleficio

You should probably replace your switch.