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So I have a 1993 camaro z28, I’ve replaced the coil and ICM and the car ran fine and still does but now out of nowhere when the car get hot it dies but it starts right back after a couple of minutes and drives, why can the car be dying?
 

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When you replaced the icm, did you put heat sink compound on back of icm & it's heat sink?

Because you have a 93, you can use a paperclip to short the aldl leads together and read codes. Dtc 41 & 42 are icm codes and they don't light the cel.
 

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Yes we put heat sink on the icm and I switched it out with my old icm also and same thing happened. Could it possibly be the Optispark? But I’m gonna try the paper clip today and read codes
 

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Yes, problem could be opti. When you read codes see if you also have dtc 16, & 36 which are opti codes.

I suggest you download the 93 service manual at the following link. It will have all trouble codes fully explained. As well as trouble shooting, & wiring diagrams www.mediafire.com/?40mfgeoe4ctti
 

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Okay thank you so much! Me and my grandfather are gonna try and tackle it today and see how it goes and I’ll get back to if I find the problem
 

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Well we replaced the Optispark and now the car doesn’t die anymore but just another question, I was just wondering how come when I go to start the car in the mornings it seems the car doesn’t want to start but after a couple of times of trying to start it it finally turns over and stays on but if I give it a little gas it acts like it wants to die until it’s fully warm then it acts normal? Is this normal? Especially with it being colder outside
 

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You need to put a fuel pressure tester on the schrader valve on fuel rail. Do a key on prime. You should have around 43 psi. If fuel pressure doesn't get to 43 psi on first key on prime, turn key off. Then repeat key on prime. See iff fuel pressure goes up with multiple key on primes.

Start engine and let idle. Pressure should be at least mid 30's. Tape gauge to windshield and take a drive. Except for idle, all driving conditions should have around 40 psi. See if fuel pressure goes down when engine doesn't perform up to par.

Another thing to think about. If engine doesn't run well when cold. Then gets better when engine warms up, you could have a problem when engine is in open loop operation. Open loop is when engine is cold, & warming up. Closed loop is when engine has reached operating temp.

Most people have cars that run fine cold. Then give grief when they go into closed loop. A code reading would be helpful, as many codes don't light the cel. And a running sensor scan might shed some light on why your engine is temperamental.

One of the sensors that would be read with a running sensor scan with an obd 1 scanner is the coolant temp sensor (CTS) If sensor is reporting coolant temp being higher than actual coolant temp, ECM would command less fuel. Thus the hard start & sluggish performance.

With CTS reporting too low of a coolant temp, ECM would over fuel the engine when cold. Again this can cause a no start condition. And if car starts, it would run badly. There's a whole bunch od sensors that must report accurate data fror engine to run, or run correctly, if it does start.
 
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