Please help me interpret O2 readings and compression test
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My car has been running rough and has lost power. I checked the O2 at WOT and got: O2 Sensor (B1S1) = 0.956 and O2 Sensor (B2S1) = 0.919. Then I did a compression test and got:
Cyl. #1 = 167 psi
Cyl. #2 = 158 psi
Cyl. #3 = 170 psi
Cyl. #4 = 165 psi
Cyl. #5 = 165 psi
Cyl. #6 = 165 psi
Cyl. #7 = 165 psi
Cyl. #8 = 165 psi
Does any of this data indicate why my car is running rough and losing power?
Thanks,
Jim
Cyl. #1 = 167 psi
Cyl. #2 = 158 psi
Cyl. #3 = 170 psi
Cyl. #4 = 165 psi
Cyl. #5 = 165 psi
Cyl. #6 = 165 psi
Cyl. #7 = 165 psi
Cyl. #8 = 165 psi
Does any of this data indicate why my car is running rough and losing power?
Thanks,
Jim
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Dont know about the compression, but your O2's (the one little bit of info you posted) indicates you running rich.
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Thanks for the replies!
Can anyone take a guess of why my driver's side bank is running richer than my passenger side? This is confusing me and I don't know where to look.
Thanks,
Jim
Can anyone take a guess of why my driver's side bank is running richer than my passenger side? This is confusing me and I don't know where to look.
Thanks,
Jim
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Not exactly sure, I am not a tuner myself but i am learning as mucha s possible. There may be a difference in just the way the O2's are placed, distance wise from the cylinder head between the two causing a little diff. I dont think that little bit is of much concern, much like the compression your still in a safe margin. But, there could be an exhaust leak small enough to cause the difference. Doubt a vacuum leak would cause such a slight diff. Check it out and if ya find out, please post it up (this forum is my greatest learning tool).
Good-luck Charlie
Good-luck Charlie