[chevy_girl14]

I have tried to replace countless things over the past couple months and nothing has worked. I will be driving and it will just shut off with no warning and it wont turn on again until it is cold and sat for a couple of hours. I have replaced the fuel pump, ignition coil, tested the oil pressure regulator since its all on the same circuit. I recently put noid lights to the injectors to see if they were bad but the lights stayed lit which means they arent getting a proper signal. So i replaced the ecm and now it wont start at all. Do i have to reprogram the ecm before putting it in or are there other problems that could be causing this issue. Any suggestions will help greatly thanks!

 

[chevy_girl14]

I also put in new distributor and rotor cap and new spark plugs and wires

 

[130195]

There is a memory chip called a PROM, that you have to transfer from the old unit to the new, did you do that? You could always try and put the old ecm back on to see if it will start. Then you would atleast be able to see wether the new ecm is working or not

 

[RayVoy]

I suspect you have a bad ignition switch

 

[chevy_girl14]

I replaced the ignition switch as well. However i did not transfer the PROM over so i will try that. I was unsure if i had to do anything like that so hopefully that will fix the issue! I will keep you posted. Thank you.

 

[chevy_girl14]

There is a memory chip called a PROM, that you have to transfer from the old unit to the new, did you do that? You could always try and put the old ecm back on to see if it will start. Then you would atleast be able to see wether the new ecm is working or not

I put the PROM into the new one and it starts again but stalls after the engine warms up just like it was doing before. Could the PROM be bad and causing it to do this?

 

[Chesters]

Hi, I was just wondering, the ECM that u installed did not come with a prom?

I assume the prom is written on to the individual setup that it was originally installed on? Otherwise why would you have a prom right?

You can't get codes off a model this age or what? Would it throw a code with a defective string?

So you just then need to have the prom re-organized? Hey I am asking here not suggesting!

Phones are out here using a hotspot at the moment.

 

[chevy_girl14]

I suspect you have a bad ignition switch

I bought a new one and replaced it

Hi, I was just wondering, the ECM that u installed did not come with a prom?

I assume the prom is written on to the individual setup that it was originally installed on? Otherwise why would you have a prom right?

You can't get codes off a model this age or what? Would it throw a code with a defective string?

So you just then need to have the prom re-organized? Hey I am asking here not suggesting!

Phones are out here using a hotspot at the moment.

Hello, when you order a new ecm it doesnt come with a new prom so all the old settings are still being transferred over. In a case where the prom does go bad i would have to have it reprogrammed. Also my truck can throw codes but i have no check engine light and since it is old most places dont carry a code reader for it.

 

[Chesters]

I bought a new one and replaced it

Hello, when you order a new ecm it doesnt come with a new prom so all the old settings are still being transferred over. In a case where the prom does go bad i would have to have it reprogrammed. Also my truck can throw codes but i have no check engine light and since it is old most places dont carry a code reader for it.

Thanks, I wondered if it was a new unit or not. Pricy?
So with the PROM in place u are back to sq 1 ? I'm not sure but I'm thinking the program must need attention. Especially not showing a check eng lgt.

 

[chevy_girl14]

Thanks, I wondered if it was a new unit or not. Pricy?
So with the PROM in place u are back to sq 1 ? I'm not sure but I'm thinking the program must need attention. Especially not showing a check eng lgt.

It was $100 bucks for the new unit and i think its over that to reprogram the PROM. so yeah i am back to square 1 unfortunately. Some people mentioned the crank shaft positioning sensor could also be bad..i dont know if you are familiar with those.

 

[RayVoy]

If it stalls after warming, the problem could be with the O2 sensor(s). They aren't used by the PCM when the engine is cold

 

[130195]

my truck can throw codes but i have no check engine light and since it is old most places dont carry a code reader for it.

When you say you don't have a check engine light, is that in the way it that it dosnt light up/throw codes? Because the truck itself does have a check engine light, and you can actually read the codes without a scan tool

Check out this link
http://www.obd-codes.com/faq/read-gm-2-digit-obd-codes-free.php

 

[chevy_girl14]

If it stalls after warming, the problem could be with the O2 sensor(s). They aren't used by the PCM when the engine is cold

Ill have to look into that, i didnt think it would cause a problem like this. Thank you!

 

[chevy_girl14]

When you say you don't have a check engine light, is that in the way it that it dosnt light up/throw codes? Because the truck itself does have a check engine light, and you can actually read the codes without a scan tool

Check out this link
http://www.obd-codes.com/faq/read-gm-2-digit-obd-codes-free.php

My truck does have a check engine light but it isn't lit up when the truck is running. It has come on and off in the past before though and would just go away. My motor does sound strong while running though. I guess it wouldn't hurt just to try it out and see what happens at this point.

 

[130195]

Yeah give it a shot, you ain't got nothing to loose

 

[130195]

Any news ?

 

[Crispyt]

Sounds like your orginal problem is your ignition control module. once it gets hot it stops functioning. You can take it out and have it tested at autozone. make them run the test 8-10times so it gets the module hot and see if fails then.

 

[Crispyt]

When it dies out does it sputter out or just shut right off?

 

[Captn]

I had a very simular problem, i can almost promise its the ICM (ignition control module) located under the dist cap. It wouldnt ever throw a code or anything, had a couple of wise mechanics tell me to do that first but i ended up going other routes and in reality spent a whole lotta money on nothing.

I'm sure you know, but if your working in that area disconnect the battery and be sure to get some good di-electric grease and clean the contact point at the bottom of the sensor.