1990 5.7 tuned port
1 year old new fuel pump

Cranks for about 45 seconds before firing. Pulled the plugs and they were very black. Installed new plugs and wires and no change. Once running seems to be ok.

Tomorrow
1. will by pass oil switch to see if it starts fasterm incase the fuel relay is not working and the ecm is waiting for oil pressure.
2. Will turn the key on and remove vacuum line on the pressure regulator to see if fuel comes out of vacuum indicating fuel regulator defect.
3. Will see if I can rent or buy a fuel pressure guage to determine pressure.

Any suggestions welcome.

 

Dont forget to check the CTS ( coolant temperature sensor).

 

Fuel Pump relay might be bad.

Do you here the pump "humm" when you trun the key on?

 

I have a similar problem. My fuel pump and pressure are fine. I am about to have a new set of injectors put in since mine are the stock multecs that have gotten noisy. If that fixes it I will post it.

 

OHM CHECK THE INJECTORS.. CALL www.FUELINJECTORCONNECTION.COM
GET RID OF THOSE MULTECS, THEY ARE GARBAGE

 

I already checked the resistance of the injectors and they are fine. They also hold pressure fine and don't leak. The resistance can be good but the injectors can still be worn out, hence the noise. I already got my Bosch design 3 22 lbs injectors. They are going in this week, along with a 3 inch stainless steel Magnaflow cat back, and a custom wide band tune. I am excited to see how it all turns out. This has been a project in progress since last February, and it seems like it is going to be at a point soon where I will be happy with what I set out to accomplish with the car.