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He needs to check for code 11 first in the computer. If there is a Crank or Cam position sensor problem this will drop the ASD/Fuel Pump relays and cut off power to parts of the igniton system and fuel pump, thus cranking and checking for voltage will show 0 after about 3 seconds. The fuel pump will not run if the computer does not see pulses from BOTH sensors.





Overcomplicated, all you have to do is check for power at the pump and if there is no power work toward the front. Chances are he will have power and need a pump. If he was a tech and had a scanner, voltmeter and service manual the other way would be the way to go.






There wont be any power at the pump after 2 to 3 seconds after turning the key to on!! The electric pump does not recieve power all the time, if it did and you had an accident then it would spill gas all over the place and cause a fire. Checking for codes is simple and the first part of diagnostics. Using the key to retieve codes is very simple. There IS NOT Power to the fuel pump all the time...read up on the theory. With no power there due to the enginnering design your diagnostic tip is useless. No pulses from crank or cam position sensor and there is NO power at the pump.





Oh I know the theory, I have 22 years of Chrysler training to prove it. Again, if you read my earlier posts, you have to check for power WHILE CRANKING.I was trying to help the guy with his problem the EASIEST WAY with very little equipment. If he has power at the pump while cranking he need not look any further.I am done here,mojo if you have any questions, feel free to PM me. Good luck.




Once again...you will NOT have 12 volts at the pump after 2 to 3 seconds IF the Cam Position Sensor or the Crank Position sensor is faulty while cranking! Read the theory again! The fuel pump relay ONLY supplies voltage to the fuel pump when the computer sees pulses from the sensors, if no pulse(as in bad sensor) that means NO voltage. So why check for voltage on a circuit that may not have it there by engineering design? The easiest way to do this is to use the ignition key and check for error codes first. Thats not too hard is it? Dont need a scanner for this. With your theory that the fuel pump gets voltage all the time would also mean that if injectors are pulsing along with the fuel pump running and there is no spark the engine would hydrolock with fuel! No way.
Now you could jumper the relay to test the wiring back to the fuel pump but then you have to be certain that 12 volts is actually leaving the relay before you go back to the fuel pump.

To the original poster, sorry for side tracking the problem but you must receive the correct information or you will be chasing ghosts.

I also have experience of 39 years.

Regards-Stevo

When PCM does not receive reference signal from ignition system, (indicating engine is not running), then the PCM interrupts relay ground circuit and no voltage is supplied to fuel pump , ignition coil, or oxygen sensor heater element.

Last edited by Stevo; 11/02/08 12:16 AM.