starting problems
 

So I'm having a starting issue with my 928 this past winter (Nov/Dec). I'm in Ohio so When it gets cold it will not turn over to start. Yet when we had warm spells (over 60 F) it would fire right up. Now though, it will not turn over. I figured before I had it towed to a shop is there some other things i should look for? The following have been replaced:

Fuel filter
Spark plugs & wires
cap & rotor

What year car? What transmission is in the car? How many miles? Have you had the battery tested?
What type and weight oil is in your engine? When you say it won't turn over to start, do you mean it turns over too slow? Or doesn't turn over at all?

None of the replaced parts seem related to the problem, which is not enough power going to the starter motor. Could be the ground strap has internal corrosion, could be weak battery, that is where to start looking.

Also check out (Heck, just replace it) the voltage regulator. Cheap insurance in colder climates. In computer-controlled cars, it is a common, but often overlooked, failure.

If you also have battery drain and mysterious warning lights, and rough running, you might find that replacing it will cure all of them.

Thanks guys I will check those suggestions out and let you know what I find.

Just so you know: the Voltage regulator is built onto the alternator, but is obviously replaceable.

You can "test" your ground strap by using a jumper cable from the negative side of your battery to a good known ground. Easy to hook up and an easy test.

One thing I have encountered twice and what might be an issue for you since I'm thinking cold weather starting problems:

I have had 2 different starters fail to retract the starter shaft completely after attempting a start. When the shaft fails to completely retract, the solenoid will not operate and therefore the starter doesn't function at all. The cause was old grease on the starter shaft. I cleaned and relubed the shaft while it was extended and have not had an issue since on either car. I would think that cold weather might exascerbate the grease issue. YMMV.

Good luck