91 Camaro RS V6 105k, always started no problem. now it attempts to start but stumbles and dies. When very cold it runs for a few seconds before going into stumble and die mode. Code 54, fuel pump does come on for 2 seconds when turning key to on position. Disconnected fuel line after fuel filter and got good strong flow (replaced filter). Tried spraying starting fluid in throttle body, no good. Swapped fuel pump relay even though fuel pump is working, no good. I'm assuming since the pump does energize and appears to be producing a good stream post filter that the pump is working and the hose on the pump is intact (really want to avoid dropping the tank). I'm also assuming that since it attempts to start that spark is ok. Any help is greatly appreciated.

 

If you got a good shot of either and it made no attempt to start that would usualy say there is a problem with the ignition. The starting fluid would be taking the place of the fuel. But your code 54 is low voltage in the fuel pump circuit. There is a fuse. Maybe by the battery or the junction block and the oil pressure switch is also part of the fuel pump circuit. Some how the computer detected a voltage refference signal of less that 4 volts for a few secondas and put that code in the memory. I can scan and email you a flow chart for code 54 if you want. Just hit me up with an email addy.

 

Code 54 involves the entire fuel pump system, since the flow seems good,the pump is probably OK. Check the Fuel Pump relay, and the OIL pressure sender which also has a switch that sends power to the fuel pump. The oil pressure needs to rise above 5 PSI for the switch to close and provide power to the pump.

 

all three relays on the firewall are the same so I already swapped the fuel pump relay, no good. The oil pressure sending unit is interesting but wouldn't the fact that the pump comes on for two seconds after turning the key to 'on' mean it's circuit has been set? It sure seems like it is either missing or receiving an intermittent signal because as I say it tries it's hardest to run for a few seconds then gives up.

 

The pump is set to come for 1 or 2 minutes after the ignition key is turned on. If within that time the engine does not start andcause the oil pressure switch contacts close, the pump will go off. This is normal operation for these engines.

 

ive gotten this same code... and STILL DO!!


wheres the oil pressure sensor???? im gona replace that damn thing once and for all. that and the coolant temp sensor for the fan.

 

"The pump is set to come for 1 or 2 minutes after the ignition key is turned on".

do you mean the 2 second fuel pump activation when key is turned to 'on' position?

If within that time the engine does not start andcause the oil pressure switch contacts close, the pump will go off. This is normal operation for these engines.

the oil pressure sending unit is new (old one leaked), to answer 350rs it's mounted on the side of the filter stem.

while cranking oil pressure gauge is reading ok so I'm assuming the sending unit is functional.

having swapped the relay, hearing the pump run, replaced fuel filter with good flow post filter, and spraying starter fluid in intake with no change in symptoms, I'm going to focus on the ecm and it's circuitry.

 

The oil pressure being good does not mean that the switch is working properly, it only means that there is enough pressure close the contacts. However;the contacts could still be bad or not working.