Won't start when hot

[Sweedee]

been at this problem for a year. I have changed Injectors, crank sensor, cam sensor and pigtail, ICM and coil, and temp sensor. if I let sit for 45-60 minutes it fires up and runs like a champ. some suggested replace the pigtail on crank sensor which I have on order. Any other suggestions? it's a 88 with 89k on it

[DAVES89]

I would still go with a different ICM. Did you replace with the original square Magnavox coils or change to the round Delco coils?

[Ronnie]

Welcome to the forum!

 

You didn't say if it dies going down the road when it gets hot or if just won't start after you cut it off when it's hot. It would be helpful if you would make that clear.

 

Your first steps should be to determine if you have a fuel problem or an ignition problem that is keeping if from starting. Do you know?

 

I really don't expect a harness would fail when the car gets hot... although it might. There just isn't enough heat in that area. Since you have replaced so many ignition parts I would focus on fuel pressure first. If you want to start there, I wrote a tutorial for thoroughly testing the fuel pump and the fuel pressure regulator.  Fuel Pressure Testing

 

It is in three parts. You should do each one while the engine is hot and won't start.

 

• 1. Pressure Test
  
• 2. Load Test
  
• 3. Leak Down Test
  

Once you know the fuel system is good you can move on to the ignition system and other tests.

[Ronnie]

I have to agree with Dave. The Ignition Control Module is the #1 cause of not starting when hot and starting up again when the engine is cool.

[Sweedee]

starts and runs great have never had a stalling problem bought GM parts for coil and ICM.

[Ronnie]

Has anyone tested the fuel pump as described above? If not it needs to be checked.

[droid5977]

Question: Is this a crank, no start condition, or a no crank, no start condition?