402 LS2 L92 top end stuttering/down on power. Inj or valvetrain issue?
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402 LS2 L92 top end stuttering/down on power. Inj or valvetrain issue?
Drove the car yesterday with no issues; idled and ran completely normal.
Started up today and it is hesitating when leaving a stop and almost feels/sounds like I'm firing only half the motor.
No codes being thrown.
WB in drivers side going super lean.
LTFT's showing -15.6% on drivers side but -1.3 passenger side when cruising.
First time I've seen Inj Duty cycle off from side to; as much as a 3% difference eg. 2% on one and 5% on the other.
IAC's showing ~110ish; last week they were 30's at warm idle.
My first thought was valve spring but there is no extra noise from the motor and I'm not getting a misfire or any other code.
My buddy thought Inj fuse but they were fine.
He thinks maybe lifter or rocker; BUT he still thinks it's Inj related because of the Duty Cycle/Lterm/WB difference.
Any ideas?
Started up today and it is hesitating when leaving a stop and almost feels/sounds like I'm firing only half the motor.
No codes being thrown.
WB in drivers side going super lean.
LTFT's showing -15.6% on drivers side but -1.3 passenger side when cruising.
First time I've seen Inj Duty cycle off from side to; as much as a 3% difference eg. 2% on one and 5% on the other.
IAC's showing ~110ish; last week they were 30's at warm idle.
My first thought was valve spring but there is no extra noise from the motor and I'm not getting a misfire or any other code.
My buddy thought Inj fuse but they were fine.
He thinks maybe lifter or rocker; BUT he still thinks it's Inj related because of the Duty Cycle/Lterm/WB difference.
Any ideas?
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You miiiiiight be onto something
I just looked at the log; drivers side O2 Sensor STATIC at 1.107
I've never seen an O2 sensor fail to the point where it doesn't move
Wish I would've looked at the O2's in the log earlier. I could have went to the Autoparts store and got a pair. Hopefully that's all that's wrong.
I'll update tomorrow. Thanks guys!!!
I just looked at the log; drivers side O2 Sensor STATIC at 1.107
I've never seen an O2 sensor fail to the point where it doesn't move
Wish I would've looked at the O2's in the log earlier. I could have went to the Autoparts store and got a pair. Hopefully that's all that's wrong.
I'll update tomorrow. Thanks guys!!!
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O2 sensors replaced and problem solved.
Since I'm running the car with just a pair of O2 sensors and air temperature it makes sense that a sensor failure will cause a LOT of issues lol.
Side NOTE: the guys at my exhaust shop are all import Honda/Toyota tuners.
After driving my car around for a while they fell in love with the "smoothness, immediate response, and how daily-driver friendly it is."
2 of the mechanics are dumping off their import race cars and looking for LS1's
Since I'm running the car with just a pair of O2 sensors and air temperature it makes sense that a sensor failure will cause a LOT of issues lol.
Side NOTE: the guys at my exhaust shop are all import Honda/Toyota tuners.
After driving my car around for a while they fell in love with the "smoothness, immediate response, and how daily-driver friendly it is."
2 of the mechanics are dumping off their import race cars and looking for LS1's