Chevrolet Repair/Truck Keeps shutting off
QUESTION: I have a 1998 Chevrolet K1500, 5.0 liter engine. I will be driving and the truck will just shut off, no sputtering or anything, just quits. The truck will start back up but may do it again in a short time, the way it does it is the RPMs will go to zero, the engine is still "on" I press the gas pedal but no acceleration or power, then it dies but will start right back up. I did have a code that my EGR valve was stuck open, I replaced the valve and she is still doing it, in fact it is getting worse. One time she was in park running and she did start to loose power but then came back up to normal. I checked the battery and connections, all were fine.
ANSWER: HI MATT, THE ONLY WAY TO REALLY TELL WHAT IS GOING ON WOULD BE TO DO SOME DIAGNOSTIC WORK. THIS TO ME SOUNDS LIKE A IGNITION FAILURE. A EGR VALVE THAT IS STUCK OPEN WOULD CAUSE A STALLING PROBLEM WHEN AT IDLE, BUT THIS PROBLEM IS NOT WHAT IS GOING ON HERE. MY GUESS IS A IGNITION CONTROL MODULE [ICM] THESE THINGS HAVE HAD MANY ISSUES WHEN THEY GET HOT,YOU GUESSED IT THEY JUST FAIL AND RESTART AGAIN..WE HAVE ALSO HAVE FOUND IGNTION COILS BREAK DOWN AND DO THE SAME THING....SO BEFORE SPENDING MONEY ON THE ABOVE PARTS IF YOU COULD JUST MAKE SURE THAT IT IS A IGNITION FAILURE THEN WE WOULD KNOW FOR SURE. WHAT I WOULD SUGGEST DOING IS DRIVING THE TRUCK TILL IT GETS WARMED UP, SHUT IT OFF AND PULL A IGN WIRE OFF A SPARK PLUG AND HOOK IT UP TO A SPARK PLUG THAT YOU HAVE AROUND THE HOUSE OR GARAGE,[IF NOT GET ONE] LAY THE PLUG DOWN ON SOME TYPE OF METAL AND START THE ENGINE, THERE SHOULD BE SPARK THAT YOU CAN SEE AT THE SPARK PLUG TIP ...NOW HAVE A FRIEND OR WHOEVER GET IN THE TRUCK AND PUT IT IN GEAR AND RAISE THE IDLE UP JUST A LITTLE, WHILE YOU WATCH THIS SPARK PLUG,,HOPEFULLY THE ENG WILL FAULTER WHEN DOING THIS. IF THE SPARK STOPS AT THE SPRK PLUG WHEN THIS HAPPENS YOU KNOW NOW THAT IT IS A IGNITION FAILURE.THINGS LIKE THIS ARE HARD TO DIAGNOSE..THE ABOVE PARTS ARE NOT THAT COSTLY IF NEEDED. LET ME KNOW HOW YOU MAKE OUT.GOOD LUCK TOM...
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QUESTION: Hi, thanks for the info, I will try it, can I just set the spark plug on some type of metal on the engine, would that cause a short or anything like that?
ANSWER: HI MATT, THAT WILL WORK OUT JUST FINE.WILL NOT CAUSE A SHORT....YOU ARE LOOKING FOR THE SPARK TO STOP AND THEN THE ENG DIES. OK. LET ME KNOW,,,,TOM..
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QUESTION: Thanks for your reply. Well this is where I am, had a good friend, mechanic, look over the truck, better part of a day, he thought the distributor modular needed replaced, he also suggested that before we replace that, that I should take it to the chevy dealership and have them hook it up to their diagnostic machine to make sure we are not missing something else. So here is where I am:
1. Local chevy dealership had my truck hooked up to there diagnostic machine and they found nothing wrong, according to the guy I don't even think the truck shut off on them when it was there...figures
2. Our mechanic went ahead and replaced the distributor modular
The truck ran OK for a 1 1/2 days, today she did the same thing again shut off on me four times on my way home from work. I paid a little more attention this time: Before she started to act up the engine did surge in power for a min from like 1.5 RPMs up to the 2, a mile after this happened she started to shut off on me. As I said before she will loose power, the RPMs Drop, the engine is still "on" but I give her gas and nothing happens and she shuts off. The truck ALWAYS starts right back up, I do not have to let anything cool down. I am at a loss, could it be crank shaft position sensor, fuel filter, TPS sensor, ECM????? As always any help would be appreciated.
HI MATT SOUNDS LIKE YOU HAVE BEEN HAVING ALOT OF FUN !!!! YES A CRANK SHAFT SENSOR COULD CAUSE THIS BUT I AM NOT LEANING TO THAT..[FUEL FILTER,TPS SENSOR NO WAY] [ECM ???? YES.] BUT LETS NOT ASSUME THIS,,BECAUSE THIS IS BIG BUCKS TO GUESS.. IS THERE ANYWAY THAT YOU CAN MAKE THIS ACT UP IN YOUR DRIVEWAY ???? YOU SEE WE STILL DO NOT KNOW IF IT IS FUEL OR IGNIITON..I AM LEANING TOWARDS A FAULTY FUEL PUMP,WHY YOU ASK. BECAUSE THIS DOES NOT SEEM TO ACT UP AT THE DEALER OR IN YOUR DRIVEWAY WITH NO LOAD ON ANYTHING... FUEL PUMPS WILL DO THIS..THIS IS HOW WE DIAGNOSE THIS PROBLEM..HOOK A FUEL PUMP PRESSURE GAUGE UP THE FUEL RAIL AND TAPE THE GAUGE TO YOUR FRONT WINDOW AND DRIVE THIS TRUCK LIKE YOU STOLE IT..WHEN THIS ACTS UP, LOOK AT THE GAUGE,,IF THIS GAUGE IS BOUNCING ALL OVER OR JUST GETS LOW LIKE 10 LBS OR SO.YOU FOUND YOUR PROBLEM. YOU WILL SEE WHEN THIS IS RUNNING GOOD THE GAUGE WILL BE ABOUT 35 TO 45 LBS POSS MORE BUT STEADY AND HIGH..WE HAVE HAD MANY MANY FUEL PUMPS DO THIS TO US..BUT AGAIN, YOU HAVE TO FIND THE SOURCE OF THE PROBLEM FIRST,, THEN WE CAN ATTACK IT. SEE IF YOU CAN RENT A GAUGE FROM SOMEONE IF NEED BE IF YOU DO NOT HAVE ONE. YOUR MECHANIC FRIEND SHOULD HAVE ONE FOR SURE...LET ME KNOW HOW YOU MAKE OUT, I WILL BE HERE..TOM ////PS I WILL ASSUME THE DEALER REPLACED THE IGNITION MODULE..