1995 s10 No Start

1995 s10 2.2L MPI OBD 1.5

Engine died while driving, felt like it was running out of fuel. Scan tool showed DTC code 54, Low Voltage at Fuel Pump Relay.

Spark is good, jumps a 1/2" gap, strong blue spark. Had fuel injectors tested, two failed impedance test so I replaced all 4 fuel injectors.
Replaced fuel pump, fuel filter and fuel pressure regulator. Still, no start. Fuel pressure tested at 40 PSI when key on to prime. When pump stops prime fuel pressure drops to 38 PSI.
Tested for power and signal at fuel injectors. Power side good at 12V and signal side is getting pulse.
Manual says fuel pressure should be approximately 41 PSI to 47 PSI.
Cleared DTC code and it does not come back.
I am wondering if the New fuel pump is bad, it a Delphi.

Really, after 28 views no response. I would appreciate a replay from Paul (Scanner Danner) to see what he has to say about this issue.

Hey Rick first let's try starting this truck on alternative fuel source such as starting fluid so we know if fuel is why it's not starting if it starts on alternative fuel source then we need to block the return fuel line and see what the fuel pump is capable of putting out (often times it's a regulator issue). After performing these tests let us know what the results are well be glad to walk you through getting this thing running again

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RickBewick wrote: Really, after 28 views no response. I would appreciate a replay from Paul (Scanner Danner) to see what he has to say about this issue.

Sorry it took a couple days for you to get a response on this one. We don't like any questions to unanswered!

Also, thank you for posting the year, make, model and engine size right up top along with not only a code, but a definition for that code!
It makes it much easier to find the right information to help you fix this problem!

Please understand that just because there were 28 views, doesn't mean that anyone had any constructive ideas to give you. Many views could be from guests who don't have a username and can't reply to messages.
Also understand that Paul and the moderators, and the rest of the users here are working full time jobs fixing and diagnosing the cars on our own plates so to speak.

I like Ben's approach here to just verify that the no start is indeed caused by lack of fuel.

You said the relay control side is getting pulse. Does this mean it's being energized for the 2 second prime and then turning off?
I'm not picking on you here, I just want to make sure there's not some pulsing, rapid on-off effect on the control wire.

Sorry for the frustration, I have been working on this for over a year. The pre-1996 OBD is just horrible.

As I stated in the first post, it will run on carburetor cleaner.
I am unable to plug off the fuel return line without removing the bed of the truck and this model does not have a shrader valve.
I removed the fuel filter and tested the fuel pressure before the fuel rail. Results following...

Key on engine off = 50 PSI
Cranking = 60 PSI
Key off after cranking = 68 PSI

Looks like the fuel pump is working correctly but I am getting low pressure in the system while using the fuel pressure regulator.

"You said the relay control side is getting pulse. Does this mean it's being energized for the 2 second prime and then turning off?"
Yes, the 2 second prime does come on and then turn off.

What do you guys think I should do next?

Thanks

Come to find out the issue was bad FUEL. I drained the tank and put in 5 gallons of fresh fuel a it starts right up. Problem solved. Will NEVER buy fuel in Oregon again...