Mechanics

CHEVROLET TRUCK GAS PROBLEM

1990 Chevrolet Truck • 130,000 miles

My 1990 c1500 5.7 TBI wont start unless I squirt gas in the bowls then it starts right up once started it runs fine and it never dies I can hear the fuel pump come on and onces its runing I can see a fuel comes out the injectors but when cracking there's no fuel from injectors but I took of the gas line when cracking and gas came the fuel pressure regulator is new I'm leaning towards the injectors or maybe a relay but i'm really not sure if you guys could please help me with what you guys think is wrong with it I would greatly appreciate it thanks Matt
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Matttyw20
December 20, 2012.




Check fuel pressure. Check voltage and ground at the injectors, engine cranking. Any applicable mil codes?
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JDL
Dec 20, 2012.
Just to add, engine cranking, the systems get battery voltage. Engine running, the systems get alternator voltage. The alternator voltage is higher, maybe three to four volts higher.

JDL
Dec 20, 2012.
Nope no codes when I squirt gas in the bowls it fires right up I noid tested the wires today and it flashed on both sides but no fuels comen out either injector when cracking but when I took the gas line off and cracked gas came out the fuel line and I know fuel regulators fine but once I start it by puttin gas in the bowls I look and the injectors are doppin fuel is it possible for the injectors to still be bad?

Tiny
Matttyw20
Dec 20, 2012.
And I ohm tested the injectors and I got 1.3 dont know if that good or not

Tiny
Matttyw20
Dec 20, 2012.
On both

Tiny
Matttyw20
Dec 20, 2012.
I'd still want to check fuel pressure, key on engine off.

I wouldn't think both injectors would go faulty at the same time? Unplug one injector, then crank, see if other one would spray. Then the other one.

The only difference, I can see, between cranking and running, is voltage and rpms.

I don't know where to go from here?

JDL
Dec 20, 2012.

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