View Full Version : 5.7 Cranks then stalls

11-13-09, 08:45 PM
Ok, so I had my fuel pump replaced in September. Recently, the car started needing to be cranked more and more to start, especially if I have driven it and let it sit 20-30 minutes. Now, it starts, revs normally, then when it comes down to idle, runs very low and rough, then stalls. I have to keep cranking and cranking and finally with my foot on the throttle partway, I can keep it running. I had the new fuel pump and pressure checked, and he said it is all kosher there. He recommended getting the injectors changed, but I wondered what y'all might have to say. The motor was rebuilt in March.

Also, the "Washer Fluid" light comes on at high speed (75-80 MPH). It doesn't come on bright, just kind of dull and gets brighter and more dull. All fluids seems to be circulating, and no other lights come on.

11-13-09, 09:06 PM
If the pressure is correct, it must be ignition. Plugs, wires, cap, rotor. Maybe a coil.

11-13-09, 09:07 PM
Perhaps. They should all be new. I'm going to bring it back in to have him do a more thorough diagnostic on it. The motor is still under warranty.

11-13-09, 09:12 PM
As a side note, today I spliced an EGR vaccum line. No noticeable improvement was detected.

The old line was cracked and had melted closed to one of the intake mounting bolts.

11-13-09, 10:18 PM
You can usually see if one of the injectors isnt working. Maybe an IAC and TPS issue? Maybe a code read will help.

11-14-09, 04:16 PM
OK, activated the OBD, and got Code 54 under parameter -01, indicating "Fuel Pump Relay". I used my DSM, and it said to listen for the fuel pump to activate for 2 seconds after the ignition is turned on. The pump seems to come on for 2 seconds, then stop, as the book says it should. I also switched the relay out, and the same occurred. I tried clearing out the codes by hitting "Off" and "Lo" at the same time. A past code from parameter -00 cleared and now shows 00. But the code 54 is still there. The manual said to run the vehicle for 30 seconds and see if the code clears, but it does not, indicating that the code is intermittent. The vehicle still cranks a lot before starting, and still has trouble staying running during the initial rev and fall to idle. Any ideas? If the fuel pump is still activating on ignition, shouldn't the pump not be relying on the oil pressure switch to activate it, which is what seems to be happening, if that is what is happening. I was hoping the relay was just bad, but maybe it isn't that simple.