Questionok i did as you said and i hear the pump come on when you first turn the key on then on startup i hear it again...after you crank it over for 30 sec or so it starts and spits and spudders till you give it gas then smooths out and it puffs gas smelled white smoke for a sec when finlly starts i checked the codes and i get p041 history,p095 history and s044 history evrything else is no what else do you think it could be?what do these codes mean...btw i just got the car...thanks~john
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-----Question-----
Ok first off i replaced the plugs,plug wires.and fuel filter,it runs ok for a little while maybe 15 miles then it starts running like it has a miss or something i didn't notice it till after driving it on highway for 10-15 miles every once and a while when i went to speed up it would like jump and jerk like it was missing or something then it starts doing all the time?it also is hard to start have to turn it over for like 5 or 6 sec before it starts then when you shut it off if you start it back up within 4 or 5 mins it starts fine.Tried turning key on and waiting a few sec maybe 10 and starting and the same thing..it is a 1995 Cadillac sts 4.6 northstar..but i think all my problems are coming from the same thing???PLEASE PLEASE help me.....
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Fuel pump test:
1. Get yourself a helper.
2. remove the gas cap.
3. have one person listen in the gas tank at the gas cap opening.
4. have the other person turn the ignition switch to the ON position ONLY so as the dash lights come on. Do NOT attempt to start the engine.
5. As soon as the ignition key is turned to the ON position, The person at the gas tank should hear the fuel pump run for TWO SECONDS and then it should STOP.
6. Does it ?.
7. If it does NOT run for the 2 seconds the fault is either the fuel pump or the fuel pump relay.
8. You need to put a fuel pump gage on the fuel line to be sure your getting sufficient pressure.
As soon as you turn ON the ignition switch to ON position, Just before you turn the key to the start position when the engine starts to crank over, A 2 second battery voltage signal is sent from the computer to the fuel pump relay and then from the relay back to the fuel pump in the fuel tank. This runs the fuel pump for ONLY 2 seconds of which pressurizes the fuel system in preparation to start the engine.
Once the engine starts, The computer BYPASSES the fuel pump relay and sends constant contionous battery voltage from the computer to the oil pressure switch of which is now CLOSED because the oil pressure is UP because the engine is running. Therefore the battery voltage flows from the computer, thru the oil pressure switch, back to the fuel pump to run the fuel pump constantly until you turn OFF the engine.
Therefore if your POSITIVE you are hearing that 2 second pump run just when you turn the ignition switch to the ON position ONLY, just before you turn the ignition key to the start position, I would have to say you have a weak fuel pump upon initial start up and to have the fuel pressure tested..
If you are NOT hearing that 2 second fuel pump run, Then I would say that the fuel pump relay is defective or faulty computer..
If you are hearing the 2 second pump run then the computer may not be sending a constant signal to the fuel pump either via a defective oil pressure switch or faulty ecm.
check your fuel pressure.
AnswerI do NOT like the white smoke from the exhaust and hard to start issue as this can be symptoms of head gasket failure.
P041 = No cam reference signal from ignition control module.
P095 = Engine stall or near stall detected.
S044 = Lift/Dive signal fault.
Since these are all HISTORY codes, What you want to do is CLEAR (erase) the codes from the computer and drive the car and see if any of the codes re-appear and let me know.
You CANNOT erase the codes by pulling a fuse and or disconnecting the battery.
