Hello everyone,
Vehicle:
I've got a 96' tahoe with the 5.7 vortec.
Symptoms:
When:
cruising around 60-80mph in 4th, overdrive engaged and push the throttle to maybe 80%, holding it right before it will downshift while usually going up a hill. Or essentially lugging the engine under high load. It wont do it when I let it downshift and I can floor it and it has great acceleration with no issues.
What:
it will buck/lurch/jump. It's so fast I cant tell if its pushing me forward or im dropping back. it will do this once, maybe twice. Again, fast enough that I dont hear any difference in the engine and there is no change in RPM or speed so it's not the torque converter locking/unlocking.
Parts Replaced Recently:
Spark Plugs
Spark Plug Wires
Entire Distributor assembly
Starter
Fuel regulator (May accidentally have left the small *nub* oring in there, so when putting the new regulator there's now two o-rings stacked)
Codes:
Bank 2 Sensor 2 O2 Low Voltage
(previously) System Too Lean on Bank 1 and Bank 2
My thoughts are maybe that it's either the coil (I know it's factory, and at 170k miles I feel like it could be ready to be replaced), or a fuel issue.
I have no codes that show up, other than low voltage from O2 Sensor 2 Bank 2. I suspect maybe a fuel issue as I have the stock spider assembly and reading out the fuel trims it's hanging out around +23 to +25 fuel trim for both bank 1 and too. No system too lean code however.
One other thing to note that may not really be useful but at idle it will "blub" once out the exhaust, like a cylinder missed once.
Maybe it's all stemming from that fuel regulator having the second oring smashed in there, or something else.
Any advice would be greatly appreciated!!
Vehicle:
I've got a 96' tahoe with the 5.7 vortec.
Symptoms:
When:
cruising around 60-80mph in 4th, overdrive engaged and push the throttle to maybe 80%, holding it right before it will downshift while usually going up a hill. Or essentially lugging the engine under high load. It wont do it when I let it downshift and I can floor it and it has great acceleration with no issues.
What:
it will buck/lurch/jump. It's so fast I cant tell if its pushing me forward or im dropping back. it will do this once, maybe twice. Again, fast enough that I dont hear any difference in the engine and there is no change in RPM or speed so it's not the torque converter locking/unlocking.
Parts Replaced Recently:
Spark Plugs
Spark Plug Wires
Entire Distributor assembly
Starter
Fuel regulator (May accidentally have left the small *nub* oring in there, so when putting the new regulator there's now two o-rings stacked)
Codes:
Bank 2 Sensor 2 O2 Low Voltage
(previously) System Too Lean on Bank 1 and Bank 2
My thoughts are maybe that it's either the coil (I know it's factory, and at 170k miles I feel like it could be ready to be replaced), or a fuel issue.
I have no codes that show up, other than low voltage from O2 Sensor 2 Bank 2. I suspect maybe a fuel issue as I have the stock spider assembly and reading out the fuel trims it's hanging out around +23 to +25 fuel trim for both bank 1 and too. No system too lean code however.
One other thing to note that may not really be useful but at idle it will "blub" once out the exhaust, like a cylinder missed once.
Maybe it's all stemming from that fuel regulator having the second oring smashed in there, or something else.
Any advice would be greatly appreciated!!