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No start in LA II

2K views 11 replies 5 participants last post by  99c5ls1 
Just remember that voltage doesnt do the work, amperage does, just because the circuit(wires, relay, fuses) can transfer 12.32 volts doesnt mean they can carry the at least 5 amps required to run the pump. Heres the real test.


Make a high cuurent test light out of a sealed beam(or whatever youve got) style headlamp, attach one lead from the lamp to pumps ground supply and the other to the pumps voltage supply(just like the voltmeter)

If the bulb lights at full brilliance then you know the circuits are good enough to run the pump, and youve got either a bad pump or bad pump controls.
 
So youve got a no start now, with good fuel pressure(whats the gauge read?) and spark on more than one plug??

Do you have a noid light you can check for injector control with??
If so check it out if not you can make do with out it.

Check the injector fuses, see if theres power at the fuse with the key in "RUN".

Check to see if theres power at the pink wires in the injector connectors with key in "RUN"(you can use the same headlight testlight trick).

Connect your test light(NOT the headlight one) to BATTERY POSITIVE and touch the probe to the injector control wires(the NOT pink wires :)) and crank the engine the test light should flash/flicker.
 
Okay, another thread :D

Did you try what I suggested here?

I see youve also complained about fuel pressure that wont hold with key off, this is usually related to leaking injectors or failing fuel pressure regualtors, both of these conditions will also lead to the hard starting, strong exhaust, and rough idle you're experiencing.

To check for a bad FPR, block off the return line and check to see if the pressure still drops, if it does its injectors leaking/stuck on or the check valve in the fuel pump module.

When it leaks down with the return line blocked off pull the plugs and see if they are wet to verify if its an injector or check valve issue.


Check all your vacuum hoses and fittings. Try to run the car with the MAF unplugged, see how it runs. if no change, plug it back in and then disconnect the MAP, see how it runs with MAP disconnected. If it runs noticeably better with either of these sensors unplugged then that sensor or its circuits are broken.






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