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1995 S-10 4.3L Vortec "vin W"
Engine cranks but won't start without a shot of carb cleaner in the intake. Key-on-engine-off fuel pressure reads 50 psi and holds pressure after turning the key off. Engine-on fuel pressure is about 53 psi, jumps up to 60 when given throttle, and holds pressure after turning engine off. Any ideas why this thing won't start? Thanks in advance.
Hmmm...
Fuel pressure seems fine, although on the low side of spec.
I assume that also means you're getting the 2 second key on prime, so the pump relay should be OK. (If you're not getting the two second prime, that would explain a lot.)
It keeps running after a shot of carb cleaner, so it doesn't sound like an anti theft issue.
Is there injector pulse during cranking if you don't give it a shot?
I'm split between maybe a failing crank sensor that doesn't trigger the vcm until the engine gets up beyond cranking speed, or a voltage drop on the injector circuit (battery, terminals, crappy relay contact) that is overcome when the alternator is charging.
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