1988porsche928s4

The battery is good, car lights up, clicks but nothing else when I try to start it. I lightly pressed on the brakes, moved the automatic gear selector (for giggles) to neutral and back to park. Now I'm stuck, it will not start. What are the trouble shooting steps? I'm not a mechanic but I can follow good directions particularly when there is a schematic (pics) of what to look for. My mechanic is only in the states 6 months per year (hard to find them for this car). HELP!

Mrmerlin

This is the upper half of the 14 pin connector with the top cover removed. Note the fat yellow wire, #14 this is the furthest forward and the closest to the right fender
NOTE these instructions are for emergency use only
Otherwise trouble shoot then repair the starter system.
NOTE following this procedure should result in the engine starting.

NOTE google Porsche 928 14 pin connector image before proceeding

Put into park,
Set E brake
Turn the key to run .
Open the hood .
Separate the 14 pin connector,
using the upper engine side harness with the pins sticking out,
touch the pin thats closest to the front of the car and closest to the right fender on the hot post,
This is PIN 14 the fat yellow wire its # 50 if you open the back of the connector but not necessary.

This will run the starter, if the starter just clicks and isnt turning over then your starter is bad,
if it starts then replace the starter relay.
If it starts then refit the 14 pin connector being careful to line it up then connect it

The Forgotten On

I had a large voltage drop in my 81 due to faulty wiring done by a PO. Replacing that wire fixed the issue as it would not turn over when the engine was hot.

Use Stan's method and get to your home or garage and check the resistance of the wiring and the voltage coming through that wire. It should be battery voltage when activated. My 81's was half ~7 volts when the wiring was bad.

You can also have someone hold the key all the way to the right and then tap the starter with a tire iron or 2X4 to see if it starts.

gomez123

Ground wire that's between the body and engine corroded or broken off?