1993 GMC C1500 won't start

1993 GMC C1500
280,000 MILES • V8 • 2WD • MANUAL
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38SLINGER
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truck died several times when i slowed down, won't restart
replaced plugs,wires,cap,rotor,wires,and fuel filter, plenty of spark.
check fuel pump pressure was low at 8 PSI, changed pump, now holding at 13PSI. I get no fuel spray at TBI when i try to start engine, pinched return fuel still no spray and no start. If i use starting fluid the truck will start and run for a while then suddenly stalls you can hear the injector clicking when the engine is running Checked for codes with scanner, none, Could the computer be bad, and is there a way to have it checked?
Thanks Dave
Oct 23, 2009 at 11:26 PM
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MHPAUTOS
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Hi there,

Thank you for the donation,

With the work you have already done, it is apparent the that problem is with the fuel delivery system or air monitoring system, ignition appears not to be an issue, you say that you can hear the injectors click... i would check each injector with a noid light, this will prove power supply, did you check the fuel pressure at the fuel rail? and have you checked the flow rate?
You can contact you local EFI specialist and often they can get known good test ECU to help do this tricky diagnostics, you pay just a nominal fee for the unit to be re bench tested after your trial, see if you can go down this path to prove the ECU.

Mark (mhpautos)
Oct 24, 2009 at 1:51 AM
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38SLINGER
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checked Both injectors with a noid light,shows that they are pulsing and receiving power. I checked the fuel pressure at the TBI inlet holding at 13 PSI Running or at rest. I took out ignition module and went to Advance to have checked,again. It appears to be good on there machine. Ran test 5 times, Ok each time. As it did the first time i had it checked 3 days ago. They suggested I try and new Module, END of problem. How i do hate it went a machine tells you something is good when it's Bad That lead me to look at ever thing else and not the real problem
Oct 24, 2009 at 7:39 PM
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MHPAUTOS
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So it's my fault that there test equipment fails to show the actual fault is it.
Oct 24, 2009 at 8:04 PM
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