On my '90 I'd drive for a while and then park after the engine gets hot and can't start the car when the key turns. I have to wait a while before it cools down a bit and then it starts right up. I've seen this before a while back up here and wondering what it is? I've heard it could be a coolant temp switch on the throttle body from some random post I was reading yesterday about the issue elsewhere. Is this possible? The car doesnt shut off when driving or sputter or anything, just no start after shut off until it cools down a bit maybe 10-20 minutes. At first I thought it may be the starter and/or solenoid but theres no hesitation really and she starts up consistently once its cool. I have a vats bypass switch already engaged. I thought it could be the connection wires to the battery terminals or the wires behind the battery which dont look the cleanest they can be but they all look like they're making plenty contact and like I said, it starts consistently a few times one right after the other when its cool. Checked batt, batt was full and fine and alternators fine at about 13.5. What else could this be? TiA

 

I was just reading a site with a similar prob but on TPI F Bodies....could it be the ignition module(Ignition control module) in the distributor?

 

Just so I understand....will it not crank? Or does it crank but won't fire?

 

If by cranking you mean engaging the starter, I turn the key and all I get is the brake light that goes on. You dont hear the engine engage or anything just like it would if the batts out of juice or if the starters fried. Of course cooling down for about 10 to 20 min and she starts right up. This isn't a case of "firing" hesitation or the engine not turning over.

 

more then likely starter or starter seloniod. easy to test to be sure.

 

How would you test for the start or solenoid? It seems to only not start after Ive been driving for a while and the engines extra hot. Why would this more than likely be the starter and not the ICM in the distributor if I stated that the car fires right up continuously after it cools down?

 

The ignition module isn't going to create a no-crank condition. Take your battery down to any parts store and have it load tested. If it passes, ensure all cables are tight, clean, and corrosion free. Inspect all leads on solenoid and ensure the same. If the battery passes, the connections are good, remove the starter and have it tested.

I'm betting starter. Heat produces resistance. If the starter is marginal it may crank the car when cold, but heat soaked it may have too much resistance to turn over the engine.

Should be an easy fix.

 

If I am reading you correctly the car is not cranking over. Like you said almost like the battery is dead. only a few things will cause this most likely as I stated. To test you will need 2 people. On the starter you have 2 terminals one is large and the other is small. On the large term you need at least 12 volts there at all times. The smaller one you need 12 volts when the key is turned to crank. All you need to do to test is. When the car will not start see if you have 12 volts on the large term. Then put your volt meter on the small term have someone turn the key to crank it should have 12 volts if it does you know it is the starter.

 

Another thing you can do is hook up a temp light going to the small term (s term). put one side of the light on the term and one side to ground. Run the car when it acts up look at the light if it is lit up while cranking and the car is not turning over again you know it is starter related.

 

Part of the confusion here is what do you define as a "no crank condition" in laymans terms? Am I supposed to be hearing clicking from the starter or something when I turn the key? As I said all I see is the brake light pop on in the center console as I turn the key and the car doesnt start with no sounds other than the auto fans I have set up to kick on when the keys turned. Since you say the ICM in the distributor malfunctioning wont create a no crank condition, if it was the ICM in the module should I be hearing the starter rapidly click or something as I turn the key to start it?

 

A "no crank" condition is just that- the engine does not turn over. The starter drive turns the flywheel and "turns over" the engine(crankshaft rotation). A no crank means the engine is not turning over. That means a starter or starter solenoid or current delivery to them is the problem. Your ICM in the distributor is vital for ignition, not starter operation. If your ICM is dead, your engine would still turn over by the starter but as Friz says, the ignition would not "fire".

From what you say, the engine does not turn over(the growling noise as you turn the key), and therefore we suspect the starter circuit and it's related parts.

 

Ratdude, I can always count on you to put things so eloquently.

In a nutshell, if you turn the key over and the engine doesn't rotate, the ICM will never come into play. As Ratdude said, you have an issue with battery, cables, connections, solenoid, starter motor, ignition switch, or security system starter interrupt. Since it will crank when cold, I tend to think it isn't the latter. Since it will crank cold, that also (probably) eliminates things such as starter or ring gear teeth broken.

If you turn the key and the engine rotates at full crank speed but won't start, then you have one of three problems: Fuel delivery, compression, or ignition. None of these will cause a "no-crank" condition, only a "no-start" condition.

Make sense?

Process of elimination. Start testing the components I mentioned. One of them WILL be the culprit

 

with Friz. Winnow it down with some troubleshooting.

Just for what it is worth (not much, perhaps) what you describe could be a common symptom of a connection or winding within the starter assembly opening up with heat. And, I'm not certain just what is afoot, but it is also a very common problem with certain AC Delco starters, back in the day. I've experienced several cases just like yours with that older starter type. In fact, There are heat wraps available to cover the starter with to prevent heat soaking from nearby headers.

There are newer "smaller" starters available now that will bolt right up - using a high-speed armature and reduction gears to generate some massive starter torque. Summit can help you with those.

Because I'm a "warrior" and not a "waxer", I have little patience for finicky systems. I want it to work every time I turn the key, and if a system demonstrates a common mode failure...NCRS be damned...its comin' outta there! My point is, if it is that big ol AC/Delco of the period that turns out to be a problem, I'd just replace it with a modern, high-torque one and be forever done with that problem! (But, that's just me.)

FWIW...Your mileage may vary.

P.

 

OK! My 85' is cranking, but not firing. Based off this BRILLIANT info, I'll go check my ICM on the distributor right now. You guys inspire me!

Jeff

 

Switched ICM, with no luck. Pulled plugs and cleaned, new wires, new ICM. I replaced fuel injectors 2 weeks ago, and she was running well. Did not drive for 3 days (rain), and now won't start. There is fuel in the fuel rail...so, should I try another ICM?

Jeff

 

How many lbs of pressure on the rail?

 

My 88 IROC-Z experienced that once. Replaced ignition module to cure.

Had a really confusing one once that would cause the car to stall randomly when hot. Turned out to be a bad coil wire that ohm'd out good when cold but opened up when hot. Found that one while troubleshooting one day and bumped the coil wire with my finger and it stalled.

 

That's known as "passive troubleshooting"

 

lol

 

I'm thinkin it's a pretty likely possibility its the starter like they're saying because you're right I remember there were heat wraps for them and the whole resistance idea out here in tucson it's gotta be insanely hot under a black cars hot engine in already outside 105 + temp heat especially where the starter is. But according to another website the neutral safety switch could give the same exact same symptoms so Im leanin 50 50 here. I had problems with that before and I was trying to reproduce the problem just about 20 minutes ago to no avail. Today I drove around for close to an hour in the heat, parked at home, turned the key and she starts right up. Shut her off and repeated it two times...wtf... I never got the prob reproduced again yet though to try to start her in neutral(Theres supposedly a seldom used link to the starter in neutral to bypass the switch I remember I once used long ago). I agree though 100 percent with the patience deal. I'm a no ********ter "warrior" myself. I don't like treating probs I like ridding of 'em. I'll have to have the starter tested with the meter and if all else fails just replace it. Im still wondering though if it is that damn switch considering I replaced the starter only like 2 or 3 years ago(I know they can still go out) and the starter also never hesitates when it does work...cranks like a champ.