Bad Injector or Bad O2?? Help me out
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Bad Injector or Bad O2?? Help me out
My car started misfiring extremely bad this morning. After scanning, I found that the bank 2 O2 sensor was reading about 200mv and not switching very well. I also threw a lean code on bank 1 (new O2 sensor here). So my question is, do I have a bad fuel injector? The car was definitely running lean. It was backfiring horribly. Also, my LTFT for bank 1 was all over the place from +6% to +22%; bank 2 was with in 1-2%.
Bank 1 sensor averaged 455mv
Bank 2 sensor averaged 395mv
What's going on here??
Bank 1 sensor averaged 455mv
Bank 2 sensor averaged 395mv
What's going on here??
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Bad plug can also jack readings lean as the oxygen is
passed unconsumed to the pipe. Flakey injector or its
connector / wiring could be involved. A manifold air leak
at the point where the runner meets the head would
affect a single cylinder as well.
If you can scan at high data rate, and force open loop
and have fueling near stoich, you could look for Bank 1
O2 voltage pulsations indicating a single-cylinder problem.
Looking for anything that appears different in character
from Bank 2.
Look at current misfire values for 1, 3, 5, 7 and see if one
of them acts different than the rest. Or if they are all
elevated relative to what Bank 2 cylinders show.
passed unconsumed to the pipe. Flakey injector or its
connector / wiring could be involved. A manifold air leak
at the point where the runner meets the head would
affect a single cylinder as well.
If you can scan at high data rate, and force open loop
and have fueling near stoich, you could look for Bank 1
O2 voltage pulsations indicating a single-cylinder problem.
Looking for anything that appears different in character
from Bank 2.
Look at current misfire values for 1, 3, 5, 7 and see if one
of them acts different than the rest. Or if they are all
elevated relative to what Bank 2 cylinders show.
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I have some information to add...
This started happening about 3 months ago. It has happened twice, both times in the rain. I would let the car sit for 5 minutes and the problem would go away, so I thought it was a short in my home made 'O2 extensions'. I bought new ones, and the problem went away. This morning the weather was beautiful. Also, the problem was persitant for over 30 minutes, I popped the hood and moved around the injector harness, all the injector clips to make sure there were no shorts, and messed with all wiring under the hood. Everything seemed to check out OK. But the car wouldn't run right, so I parked it and had someone pick me up.
Any additional insight would be great! Could a injector had been on the brink of crapping out on me and finally gave up?
This started happening about 3 months ago. It has happened twice, both times in the rain. I would let the car sit for 5 minutes and the problem would go away, so I thought it was a short in my home made 'O2 extensions'. I bought new ones, and the problem went away. This morning the weather was beautiful. Also, the problem was persitant for over 30 minutes, I popped the hood and moved around the injector harness, all the injector clips to make sure there were no shorts, and messed with all wiring under the hood. Everything seemed to check out OK. But the car wouldn't run right, so I parked it and had someone pick me up.
Any additional insight would be great! Could a injector had been on the brink of crapping out on me and finally gave up?
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Don't forget to check battery grounds. A bad ground can cause all kinds of wierd problems. I've had cables corrode on the inside that looked brand new on the outside that caused me problems.
Dee Jay
Dee Jay
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Well, I went to pick the car up and it ran fine until it warmed up. Then the problems resurfaced. I don't have the power cord for my laptop, so I can't trouble shoot tonight, but if anyone has any other ideas as to what it could be let me know.