bank 1 and 2 going lean
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the air injection line broke off on the passengerside manifold. i put a bolt in the hole and rerouted the air injection from the pump so it only injection to the driverside.. now both banks are coming up lean.. i find it hard to believe both o2 went bad at the same time.
Any ideas?
Any ideas?
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Sounds like a vacuum leak. Do you have an air lid or the stock air box? On the stock air box the suction for the air injection pump comes off of the intake tract. If you have left the passenger side Air Injection discharge line open you will draw air from this line through your air injection pump and into the intake tract once the pump shuts off. This would be a monster vacuum leak and throw the two above codes.
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Kevin.
it's an aftermarket lid. the leftside(driverside) air injection is still connected but the right side is not. the right side is pluged at the exhaust manifold and the air line has been removed and so all of the air is being routed to the dirverside. would you think i could resolve the problem by disconectiong the driverside aswell?
Thanks for the info
it's an aftermarket lid. the leftside(driverside) air injection is still connected but the right side is not. the right side is pluged at the exhaust manifold and the air line has been removed and so all of the air is being routed to the dirverside. would you think i could resolve the problem by disconectiong the driverside aswell?
Thanks for the info
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Kevin i am confused on how i would creat a vacum leak from the air injection. Doesnt the pump dran in outside air and inject in into the exhaust to burn off any unused vapors and make for a cleaner burn? Wouldn't the lack of O2 maybe create it to seem rich??
i am confused i need some help
i am confused i need some help
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on this 98 it never tried to pull from the air filter . the AIR pump is the pump on the driverside front down low that has its on suction from outside air. i am up for anything.
isn't it common to remove the AIR system and it not throw codes?
isn't it common to remove the AIR system and it not throw codes?
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Hmm, I can't remember the last time I looked at a stock 98 anyways.....
You can usually pull the air system and not have the car immediately throw SES codes. You just have to ensure that you properly block the hole at the header. If not you get an annoying tick and air leak into the exhaust which CAN throw a lean code for that bank.
There are only a few things that will cause both banks to throw a lean code at the same time, and that is usually a vacuum leak, bad MAF (ported etc...), or bad tune.
If what you say is true, then I don't know what it could be.
You can usually pull the air system and not have the car immediately throw SES codes. You just have to ensure that you properly block the hole at the header. If not you get an annoying tick and air leak into the exhaust which CAN throw a lean code for that bank.
There are only a few things that will cause both banks to throw a lean code at the same time, and that is usually a vacuum leak, bad MAF (ported etc...), or bad tune.
If what you say is true, then I don't know what it could be.
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Kevin,
Thanks for your responses and now that i think about it the Stock MAF was put back on. i did not know the MAF could cause both banks to go lean. i will put the SLP maf back on tomorrow and see what happens, Thanks again and i will repost what happens.
Thanks for your responses and now that i think about it the Stock MAF was put back on. i did not know the MAF could cause both banks to go lean. i will put the SLP maf back on tomorrow and see what happens, Thanks again and i will repost what happens.