94 Suburban no spark, no fuel issue
 

So I've had this 94 Suburban for 6 months or so. its a 94' silverado, 5.7 TBI, 4L60E, 2wd. It is an unmolested truck. Since I've had it I get a check engine light on most trips 15 min of driving or longer. doesn't run bad, doesn't flash, just comes on and sometimes goes off. Last Wednesday I took a trip about an hour away pick up a motorcycle towing a small trailer (5x8) flatbed. Got home, parked. unloaded bike. started burb up backed trailer into back yard and parked it. went to start burb a few hours later. It will crank but nothing. took off air cleaner and smelled fuel. had someone crank it while I watched and nothing squirting, with or without opening the butterflies. checked the injectors and they are getting power but I don't have a noid light. The injectors function correctly when tested. gaskets were brittle so I placed all of them with a rebuild kit and put everything back together. I'm getting fuel to the TBI and the pressure tested @11 PSI. Checked for spark, and no spark either. replaced ignition module, and coil. There is power to the coil (pink wire, black connector) and it slightly dims with a test light when cranking and is at its brightest with just the key on. No spark at the coil with with 1/4"gap.

I got a OBD1 reader to try to pull codes but I guess I had already erased them disconnecting the battery so it flashed 12 as everything is normal. I searched for a crank sensor, even removing the starter but there is nothing there. I even replaced the ECU with a used one (same #) and no difference.

I haven't had any issues with my oil pressure gauge, but I feel my temp gauge reads lower than it should, about 140 most of the time. In fact seems like i remember the gauge spiking to 200 for 20 seconds on the trip home last I drove it but then returned back to its "normal" 140. It doesn't normally spike like that, it stays at 140 once its warm.

I hate to keep throwing parts at it, but thinking I should throw a coolant temp sensor? Oil pressure switch at it? Any help greatly appreciated.....

Re: 94 Suburban no spark, no fuel issue
 

No spark or fuel? That is a weird problem and the two don't sound related on the surface. They are two different systems.

There is a trouble shooting info at the top of the forum. I would do some trouble shooting rather than throw parts at it. New parts are often crap so you could install a bad part and maket troubleshooting even harder.

Here is another I saved. https://easyautodiagnostics.com/gm/main-index

Re: 94 Suburban no spark, no fuel issue
 

Actually they do sound related. The computer needs to receive a distributor reference pulse from the distributor module to trigger the injectors.

Work on the no spark problem.
You already replaced the module so check the pickup coil.
Pickup coil testing:
500 to 1500 ohms between terminals.

Infinite from one terminal to ground.

When testing the pick-up coil resistance, the key should be off, and the pickup coil should be unplugged from the distributor module.

These distributors can also have problems because of loss of magnetism needed for the pickup coil to work.
If the magnetic material on the shaft in the reluctor wheel area is cracked into pieces replace the shaft or the whole distributor. This problem shows up at low RPMs. (& starting)

Re: 94 Suburban no spark, no fuel issue
 

Thank you both for the input. Bad oil pressure sensor was the culprit.