Hey guys,
Ive been having some issues with my sierra for about a week now.
It started with my check engine light coming on solid, not flashing. (The light never flashes, just stays solid). When i scan the code it reports P0301 cylinder 1 misfire detected and then P0301 misfire cylinder 1 *pending*
I dont really notice any difference driving, only at idle and below 1000 rpm. It idles rough and goes up and down by a few hundred rpm.
The light went off last nite while driving but then came back on this morning on my way to work. (for the first time)
Steps i have tried to solve the problem, all have failed,
- Erased code, reappeared within 15mi.
- Replaced all 8 spark plugs with denso double platinum @ .040
- Replaced all wires with an autolite performance set.
- Swapped new wires and new plugs between cylinder 1 and 3.
- Swapped the coil pack from 1 and 3.
- Ran 2 bottles of lucas injector cleaner through two tanks of gas.
- Cleaned the mass airflow sensor.
- Cleaned the inside of the throttle body.
Im not really sure what to do next, im kinda doubting its the intake leaking because wouldnt that cause the p0300 random misfire code?
The engine has 110K on it. An ran great until that light came on.
What should i do next? Do our injectors clog easily? Could a clogging injector even cause a misfire?
Truck is a 99 sierra nbs, only mods are a cai and flowmaster 10 series muffler.
Ive been having some issues with my sierra for about a week now.
It started with my check engine light coming on solid, not flashing. (The light never flashes, just stays solid). When i scan the code it reports P0301 cylinder 1 misfire detected and then P0301 misfire cylinder 1 *pending*
I dont really notice any difference driving, only at idle and below 1000 rpm. It idles rough and goes up and down by a few hundred rpm.
The light went off last nite while driving but then came back on this morning on my way to work. (for the first time)
Steps i have tried to solve the problem, all have failed,
- Erased code, reappeared within 15mi.
- Replaced all 8 spark plugs with denso double platinum @ .040
- Replaced all wires with an autolite performance set.
- Swapped new wires and new plugs between cylinder 1 and 3.
- Swapped the coil pack from 1 and 3.
- Ran 2 bottles of lucas injector cleaner through two tanks of gas.
- Cleaned the mass airflow sensor.
- Cleaned the inside of the throttle body.
Im not really sure what to do next, im kinda doubting its the intake leaking because wouldnt that cause the p0300 random misfire code?
The engine has 110K on it. An ran great until that light came on.
What should i do next? Do our injectors clog easily? Could a clogging injector even cause a misfire?
Truck is a 99 sierra nbs, only mods are a cai and flowmaster 10 series muffler.
