Lean in both banks plus multiple misfires

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tommypvt

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no exhaust leaks? sound stupid i know, but i have seen on vw's, having a exhaust leak near the o2 (have seen it a few inches behind the o2 even do this) it creates a vacuum, sucks fresh air INTO the exhaust, and the 02 will read that fresh air and call it a lean condition....probably not your problem but throwing it out there....
how did the plugs look? if its o2 or exhaust related, they will be black or look/smell like they were running rich. the computer will adjust for lean/rich to a point then throw a code. so if they look good or light, you know you are lean and its the intake side, if they are dark then the computer is reading the o2, and exhaust leak and adding fuel when it doesn't need it, so you will get unburned fuel and that can cause a misfire.....the plugs are an awesome way to figure out whats going on, even on an electronic controlled engine....

Plugs look good and light. I dont think there are any major leaks. It is an old exhaust but seems like it is solid or patched where it needed it. Nothing really obvious that i can hear or feel.
 

tommypvt

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Just went to my neighbors and pulled the maf replaced the one in my truck. Cleared codes and lean both banks and misfires came back. So I guess just wait till the new spider comes in.

Also my heater blower decided to stop working today. New resistor and blower motor prob two months old. I swapped in his hvac panel and same thing. The previous owner had it hot wired to a switch. I fixed the harness with a new plug and had it working for a while but no go anymore.
 

tommypvt

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So who doesnt tighten down the throttlebody to the intake manifold? The previous owner of this tahoe I guess. Well its getting an updated spider anyway. Hopefully all problems will go away.
 

slowburb

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There's your lean condition, man. It wasn't the intake, it was the intake.
 

tommypvt

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Yup.

Just cleared codes and took it around the block. Runs sooo much nicer. Read codes again. Has the p0300 misfire code pending as well as a p0507 rpms exceeding expected? No clue. Going to replace distributor next hopefully that will do in the misfires. It has new ac delco cap rotor and wires. I was hoping the spider would help but it prob is a disty issue.
 

tommypvt

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Oh and fixed the blower issue just the pesky ground on the blower. I think I had the connector on upside down and it was wiggling itself loose. No lean codes on the way to work this morning but getting random misfires and for some reason a cylinder 7 misfire. Ordered the distributor last night I will swap that in Friday when it gets here. I hope that at least gets the CEL off for a bit.
 

tommypvt

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New distributor is in still getting some misfires. Need to replace bank 1 spark plugs Maybe that will help a little.
 
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tommypvt

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Ugg totally scewed now. Got the distributor in and set with dashcommand. It was at like 3 degrees and I was getting some misfires so tried to get it closer to zero and now the idle is awful and it barely runs. Getting really bad misfires in 5 and 7 now. It seems like most of the misfires are limited on bank 1. So maybe o2 sensor but 5 was acting fine and 7 and 3 were giving misfires earlier.

Really have no clue. I tried a different new cap but still idling horrible. At a total loss. Thought i was really close now no clue.
 
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