QuestionQUESTION: I have a 1990 Chevy k1500 4wd that sputters in every gear. I thought it might have been the clutch going out so I replaced it. It is still doing the same thing. It's almost like the fuel isn't getting into the engine properly. I have checked everything I know to check and can't come up with any answers. Any feedback you could give me would be greatly appreciated.
ANSWER: HI BENJAMI, THERE COULD BE MANY THINGS THAT CAN CAUSE WHAT YOU ARE EXPERIENCING.IF YOU HAVE A FUEL PRESSURE GAUSE THIS WOULD BE THE PLACE TO START OUT WITH. WE NEED TO KNOW WHAT THE PRESSURE IS,WOULD LIKE TO SEE AROUND 30 TO 35 LBS FOR TBI.[THROTTLE BODY INJECTION] IF FUEL PRESS IS OK THE NEXT STEP IS IGNITION SYSTEM FAILURE. SUCH AS BAD COIL,PLUG WIRES,DIST-CAP. WHEN YOU SAY SPUTTERS,I WILL ASSUME YOU MEAN MISFIRE,LIKE NOT RUNNING ON ALL 8 CYLINDERS ??? OR DO YOU MEAN JUST NO POWER. WHICH COULD BE FROM A FAULTY FUEL PUMP...IF YOU CAN GET BACK TO ME WITH MORE INFO THIS MAYBE HELPFUL TO ME.. LET ME KNOW,,TOM..
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QUESTION: Where would I check the fuel pressure? And yes, it is more like a misfire, but it's a 6 cly a d not an 8. And is the fuel pump in the gas tank or is it in line between the tank and the engine?
AnswerHI BENJAMI,SO IN STEAD OF THE ENG RUNNING ON 6 CYL'S IT IS RUNNING ON 4 TO 5 MAKING IT SKIP.. SO IF IT IS TRULY A MISFIRE THEN WE CAN RULE OUT THE FUEL PUMP. TO ANSWER YOUR LAST QUEST,THE FUEL PUMP IS IN THE TANK,SO YOUR TANK WOULD NEED TO BE DROPPED IN ORDER TO REPLACE THE PUMP. FUEL PRESSURE IS CHECKED AT THE TEST PORT BEHIND THE TBI UNIT,ON THE MAIN FUEL LINE.[PRESSURE SIDE]THIS LOOKS LIKE A VALVE CAP LIKE WHAT IS ON YOUR TIRES. REMOVE THE CAP AND THERE IS A VALVE THAT THE PRESSURE GAUGE WOULD SCREW INTO TO CK PRESSURE. HOWEVER THE WAY THIS SOUNDS TO ME IS A BAD IGNITION SYSTEM..HAVE YOU EVER TUNED THIS ENG, SUCH AS PLUGS WIRES,DIST CAP, OR ROTOR ? I HAVE ALSO SEEN MANY FAULTY COILS ON THESE 6 CYL'S WHICH WILL CAUSE A MISFIRE [SKIP] BECAUSE OF A WEAK SPARK..IF YOU HAD A SCAN TOOL WE COULD WATCH WHICH CYLINDER IS DROPPING OUT,NOT FIRING LIKE IT SHOULD...NOW FOR THE BAD NEWS.IF THIS PROBLEM IS NOT A IGNITION FAULT, THEN THE ONLY THING LEFT IS INTERNAL PROBLEMS, SUCH AS BURNED VALVE,STICKY VALVE,TIMING CHAIN JUMPED..AT THIS POINT IT MAY MAKE SENSE FOR YOU TO GET THIS ENG SCANNED TO FIND THE PROBLEM AND IF A FAULTY IGNITION SYSTEM YOU CAN REPLACE THE PARTS YOURSELF,,UNLESS YOU WANT TO GAMBLE AND REPLACE THE IGN PARTS [AS I SAID ABOVE] AND HOPE THIS TAKES CAR OF IT ??? I HOPE THIS HELPS YOU AND IF YOU NEED MORE INFO PLEASE GET BACK TO ME..WHEN YOU ARE ALL DONE WITH THIS PROBLEM WOULD YOU MIND RATING MY ANSWER. THANK YOU VERY MUCH,,,TOM..
