Sputtering and dying
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Sputtering and dying I have a 03 chevy 6.0 2500hd it has a has a very slight but noticeable missfire when you try to rev it it hesitates but then revs good then when revving down it sputters out n tries to die or dies , it also sputters n dies when going up a hill any ideas?
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you probably got more than one possible cause
first check the crank position sensor and replace it with an OEM one, aftermarket ones always act weird on these 6.0 trucks
second check the ignition coil harness, this actually happened to me before. i found the coil harness wasn’t getting 12v power. i tested the wires and it had no power so i ran an external 12v feed to it and the problem went away
also quick question — when the truck is in Neutral and you floor it, does it rev up smoothly to full RPM or does it hesitate and misfire?
first check the crank position sensor and replace it with an OEM one, aftermarket ones always act weird on these 6.0 trucks
second check the ignition coil harness, this actually happened to me before. i found the coil harness wasn’t getting 12v power. i tested the wires and it had no power so i ran an external 12v feed to it and the problem went away
also quick question — when the truck is in Neutral and you floor it, does it rev up smoothly to full RPM or does it hesitate and misfire?
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So I replaced the coil packs and the missfire seems to have went away I also changed the maf sensor yesterday but it would hesitate a sec and then rev up nice and smoothly then would true and die when revving down but I didn’t have that issue today I took it for a drive and it drove fine for about 20 minutes then it started stuttering out then died at the light and wouldn’t start for a couple minutes
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now that you said it dies after 20 minutes and won’t restart right away, that really sounds like a crankshaft position sensor.
on these 6.0 LS engines the crank sensor fails when it gets hot, the PCM loses the RPM signal so it shuts off fuel and spark, that’s why it stalls and won’t start again until it cools down for a few minutes
I would replace the crank sensor with a genuine GM/ACDelco one only, not aftermarket. this is a very common issue on 99-06 trucks and the symptoms you described match it perfectly
on these 6.0 LS engines the crank sensor fails when it gets hot, the PCM loses the RPM signal so it shuts off fuel and spark, that’s why it stalls and won’t start again until it cools down for a few minutes
I would replace the crank sensor with a genuine GM/ACDelco one only, not aftermarket. this is a very common issue on 99-06 trucks and the symptoms you described match it perfectly
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if the crank sensor doesn’t fix it then check fuel pressure, these trucks need around 58psi and a weak fuel pump or clogged filter/regulator will make it stall after driving and die at stops
also check engine grounds behind the heads and on the frame, LS trucks act weird when the grounds are bad
and try this, next time it dies open the gas cap and try to start it. if it starts right away then the tank vent/EVAP is clogged and pulling vacuum in the tank
also check engine grounds behind the heads and on the frame, LS trucks act weird when the grounds are bad
and try this, next time it dies open the gas cap and try to start it. if it starts right away then the tank vent/EVAP is clogged and pulling vacuum in the tank
