VEHICLE AID - Car Won't Stay Running

ASKED BY:
RGMANN

ASK DATE:
Apr. 15, 2005

CATEGORY:
Mechanical | Cooling System

Car Won't Stay Running

Vehicle: 1988 CHEVY CAVALIER 4 CYL. AUT

MY CAVALIER STARTS AND RUNS JUST FINE UNTIL IT GETS WARMED UP,THEN AFTER DRIVING IT A FEW MILES IT STARTS RUNNING REALLY BAD TO THE POINT THAT IT DIES EVEN WITH THE GAS PEDAL TO THE FLOOR .IF I SHUT IT OFF AND AND LET IT SET FOR A MINUTE OR 2 IT WILL RESTART AND LDLE JUST FINE ,UNTIL I START DRIVING IT AGAIN THEN ITS THE SAMETHING ALL OVER AGAIN.ITS ALMOST LIKE ITS VAPOR LOCKING OR SOMETHING BECAUSE IT WILL IDLE IN PARK AS LONG AS I WILL LET IT SET AND RUN. COULD THE SCREEN ON THE FUEL PUMP CAUSE THIS,I HAVE ALREADY CHANGEN THE FUEL FILTER.

COMMENT BY:
steve

COMMENT DATE:
Apr. 16, 2:29 AM

QUALIFICATIONS:
Site Rank: 9

If the suction line to the petrol pump is too close to the pipe from the thermostat housing to the radiator, heat build-up in the fuel line can cause a vapour bubble to form, particularly if the fuel flow is slow (at idle) or non-existent. When this happens, the fuel pump suction stroke can cause the vapour bubble to expand and contract instead of pulling fuel along the line. The result is that the car will not restart until it has cooled down sufficiently for the vapour lock to have gone.

Cure - route the fuel suction pipe away from the water pipe. It should run up the left suspension tower. It should not be necessary to shield or lag the rubber pipe that connects the fuel line to the pump suction if a clearance of at least 1 inch is maintained between the fuel pipes and the water pipe.

If the car didn't stop of it's own accord, but simply won't restart again until it's cooled down a bit, (typically in a petrol station after filling up), the cause could be the auxiliary starting circuit.

ACCEPTED ANSWER

COMMENT BY:
joe allen

COMMENT DATE:
Apr. 16, 10:53 AM

QUALIFICATIONS:
ASE Certified
Site Rank: 1

Well not that i contest what we are saying here but on this car it is unlikely that we are going to see this problem out of no where.

Are there any engine lights on ? when did this start occuring ? Have you changed any parts on the car that we should know about. Were there any symptoms leading up to this.

Any info you can give will help us out greatly.

COMMENT BY:
mustanggirl

COMMENT DATE:
Jul. 25, 4:27 PM

QUALIFICATIONS:
Site Rank: 37

I am having the same problem but I know there is a few thing that it could be!!!!

1) You have a pinched fuel line
2) Might have debris
3) It might be that your carburetor

You might not be getting the right amount of fuel to your engine!!!!!

COMMENT BY:
mustanggirl

COMMENT DATE:
Jul. 27, 7:42 PM

QUALIFICATIONS:
Site Rank: 37

Ok here is the problem with your car!!!!! if you did not fine out already!!!! but my car has been doing the same thing and i did some work on it and found out that it is called a vapor lock!!!!!!!

take a hammer to you carburator very lightly and the valve that is in there will open up and work properly!!! but make sure you don't hit it hard or you eill do some damage to it!!!!!

COMMENT BY:
RGMANN

COMMENT DATE:
Jul. 28, 2:00 PM

QUALIFICATIONS:
Site Rank: 12

THANKS FOR THE ANSWERS BUT THE PROBLEM HAS BEEN FIXED . EVERYBODY GAVE ABOUT THE SAME ANSWER AND I ALSO THOUGHT IT WAS IN THE FUEL DELIVERY SYSTEM . WE ALL WERE HALF RIGHT , THERE WERE 2 PROBLEMS , THE THROTTLE POSITION SENSOR WAS GOING BAD AND ON THE BACK OF THE ENGINE IS THE OIL SENSOR AND IT WAS LEAKING OIL . AFTER MORE INVESTIGATING I FOUND THAT THERE WERE 2 DIFFERENT TYPES OF OIL SENSORS FOR THAT CAR , A 2 PRONG AND A 3 PRONG . THE OIL SENSOR I HAVE HAS A SENSOR FOR THE FUEL PUMP ALSO , ( IF THE OIL LEVEL GETS LOW IT SHUTS DOWN THE FUEL PUMP ). WITH THE SENSOR LEAKING IT SENDS A FALSE READING AND WAS MAKING THE FUEL PUMP STUTTER . I CHANGED BOTH OF THESE AND IT FIXED MY PROBLEM .