Starter help - missing wire!
 

A week ago my '83 SCarrera (3.2L Euro engine) stopped starting. In the weeks prior it had some trouble starting - I would turn the key, the starter seemed to engage but it would not have enough juice to turn the engine over. After a few long seconds of cranking it would turn over. Now it won't start at all. Current symptoms are the same, starter seems to engage, fan turns slowly, but engine won't over.

Battery is new so I figured I'd install a hi-torque starter as I crawl under the car and diagnos the problem. According to the installation instructions posted in the tech forum, Step 1 is to remove the 'two yellow wires'. Here is the problem - I only have one yellow wire! One spade connector has nothing attached to it. There doesn't seem to be a stray wire hanging either. It seems like it was never there.

Would the engine have started at all without one yellow wire on the bottom being hooked up? Did this missing wire cause the slow failure over time? What do I do now? Where does this wire go and how do I fabricate a new one?

Here is a picture:

http://forums.pelicanparts.com/uploads/Starter 001.jpg


My ignition system is not stock, not sure if thats a factor. Here is a pic of the set-up:

http://forums.pelicanparts.com/uploads/Omnipak.jpg


I am under the car now - please help!

The solenoid that the two yellow wire just need a connection to the switch and a connection to the ground. If you have an ohmeter disconnect the yellow wire and see if that wire is the ground wire. If it is not the ground wire you can make a wire with a connector to attach to the empty spade connector and ground the other end of the wire.

Before replacing the starter check to see if this fix your problem. It looks like you are not energizing the solenoid.

Looking at the Bentley manual, it looks like one of the yellow wires goes to the ignition switch and the other goes to the cold start injector. It looks as though the cold start injector wire is missing. Are you saying the cold start injector is in the solenoid and the other end is supposed to be grounded?

The solenoid requires two wires for the coil in the solenoid to energize. one wire would come from the ignition switch the other wire would go to chassis ground. When the solenoid is energized it closes two contacts internally. one contact has the heavy battery cable attached to it the second contact connects to the starter. The starter requires battery voltage and a chassis ground for it to operate. It is possible that your solenoid is finding a chassis ground other than the ground terminal on the solenoid. Attached is a basic diagram of the solenoid/starter circuit. In the diagram where the ignition (starter) switch makes contact with the solenoid coil, the coil goes to ground on one side and on the other side the coil is wired to the brush on the comutator of the starter motor. The other brush is tied to ground. So if the solenoid ground wire is missing it is still possible for the solenoid to energize by uing the circuit through the starter brushes to ground. http://forums.pelicanparts.com/uploa...starterckt.gif

http://forums.pelicanparts.com/porsche-911-technical-forum/94629-high-torque-starter-different-connections.html?highlight=starter

I don't believe your car ever had the second yellow wire (only the turbo's did?) I'd clean and check the grounds before going to the trouble of installing the new starter.

I think I understand now. Looking at the Pelican catalog, I only see cold start valves for the 3.0 SC engine and the 930. There is nothing listed for the 3.2 Carrera engine so my car probably never had the second yellow wire.

Should I assume then that the solenoid is receiving a ground from somewhere else or should I try to fabricate a a ground for the second post? I'm guessing I don't need to fabricate a ground wire since it seems it was designed without a ground on that terminal. I now think that second terminal is only used when using the starter in a 3.0 SC engine or 930.

The starter does not have a ground wire per se. The starter establishes it's ground through it's housing which is bolted up to the transmission. There is a ground strap between the transmission and the body which completes the ground path in this area. The battery's ground cable is bolted to the body up front in the trunk area. Therefore, the ground return path is starter housing to transmission housing to transmission ground strap to body (current travels through the steel of the body) to battery ground strap to battery ground (negative) terminal. Check, clean, lightly coat with dielectric silicone grease the contact surfaces and retighten those ground straps. Cheers, Jim