Sometimes when I turn the key nothing happens.

[dietrich]

Hello all,
My 944 has developed a starting issue. About 40-60% of the time when I turn the ignition key all I hear is a click and nothing happens. Other times it starts right up and runs perfectly. It has three months on the battery and the cables look fine. I've looked through the other threads to see if this is specifically what happens when the DME relay goes bad. Any ideas would be very helpfull. Regards Dietrich

[jmd_forest]

Dietrich,

I am assuming by "click" what you are hearing is the starter solenoid and the starter motor does not engage? Regardless, the DME Relay does not control the starter motor and the starter motor should operate even with a defective DME relay.

Assuming the click IS the starter solenoid and the starter motor is not engaging, you probably have a problem in the starter circuit. Possible common issues are:

1) Bad ignition switch
2) Bad ground connections
3) Bad battery connections
4) Corroded battery cables (hot or ground cable could be corroded inside the cable sheathing causing a voltage drop over the length of the cable)
5) Bad or corroded connections at the starter motor/solenoid
6) Bad solenoid
7) Bad starter motor.

I would start with (in order of easy to hard and cheap to expensive, in my opinion):
1) Cleaning up the battery terminals and battery cable connections. Use fine sandpaper to clean up the battery posts and the inside of the cable connectors.
2) Cleaning up the ground connections
3) Cleaning the solenoid connections
4) Cleaning up the actual solenoid: Remove starter, remove solenoid from starter, use fine sandpaper to clean up any rust/corrosion off of solenoid plunger and plunger cavity, giveplunger a shot of WD-40 and reassemble. Clean up the mating surfaces of the solenoid to starter and starter to block while you're at it. Not a bad idea to test the starter while off the car either. If the starter or solenoid is bad, replace it before reinstalling
5) Test and replace cables, if necessary (Use a DVM to test resistance of cables. They should have essentially zero resistance. Disconnect both ends before testing)
6) Replace ignition switch

jmd_forest

[Eldorado]

my vote is for a faulty ignition switch.

if you dont hear the starter, or *anything*... then i'd say the switch was bad.

dont buy the porsche one... go to volkswagon and it's only about $13.

[hpservertech]

I would say it's the ignition switch. Replace it and then go from there. Next would be the starter, but I bet it's the switch.

[Eldorado]

put a volt meter on the starter... if you turn the key and see no voltage, then you know its the switch.

[Razorback1980]

A "click" usually means weak voltage to the starter solenoid. The hard part here is waiting for the car to be in that condition so you can test it. Of course you can test it any time and the voltage will still show a degradation but not to the point where it's causing a problem.

It's probably going to turn out to be the battery cables or thier connection points. Get a volt meter. Check the voltage on the battery terminals. You should have the same voltage on the large post of the starter solenoid. If not, then change your meter to ohms and check the ohms between the negative post of the battery and then engine block. Should read infinite. If not, then the negative battery cable is bad or needs to be cleaned on each end and reconnected. If the ohms check good, then your positive battery cable needs cleaned or is going bad. Clean and/or replace. The small wire on the starter should have 12V to it while the switch key is in the start position. If it doesn't then look to the switch key.

[jmd_forest]

Razorback,

Don't you mean the ohms should read zero. If it reads infinite between the block and the negative post it means the negative cable is disconnected or you've got one hell of a corrosion problem.

jmd_forest

[Razorback1980]

I hate it when that happens....you are correct. Look for a zero reading. Thanks.