I am trying to chase down an intermittent starting problem. I have read many posts on starting problems. So, I will check on the usual suspects (crank position sensor, fuel pump, distributor cap/wire moisture....etc.) But rather than blindly replacing parts and hoping the problem gets fixed, I like to have a better understanding of all the systems.

So far, it happened twice on me (about two weeks apart), each time with different symptoms. First time it would not crank at all. Trying few hours later, it started. I took it for a drive and the car performs normally.

The second time, two weeks later, the engine cranks (strongly) but would not start. Again, few hours later, it started normally as if nothing happened.

The battery is healthy and fully charged. I have a new DME relay. So, I can eliminate these two as the source of the problem.

My question:
If it is a faulty crank position sensor, would the engine crank at all?

 

with a faulty crank sensor would not make the engine not crank. when it does not crank you'll need to check the starting system. If it cranks and don't start you'll need to check for spark and fuel. A faulty ignition switch could coarse this problem. With out seeing it it's just a guess for me.

 

What temp was the engine at during these issues? Hot no start is often a sign the starter motor is on the way out.

 

Both times the engine was cold. I tried first thing in the morning. So, based on what wallra said, there could be two different issues.

There could be another factor at play here. I had to park the car outside for about a week or so. It rained a couple of days during that time. So, it could be moisture as well.

So, what to do, where to start??!!

 

Like others said:

-consider checking starter motor
-consider checking the ignition switch
-also check your car's grounds

That's all I can initially think that would cause in your 964 an intermittent no crank condition.

 

DME relay ?

 

Thanks all. When I get a chance to poke around, I will report back on what I found.

A8KED, the DME relay is new.