need help car is misfiring
#1
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my car is misfiring once it warms up. i thought it may be a intake leak from my plug after the deleted egr but it seems to be happening after it is drven and then shut off for like 10 min then re driven. can anyone give any input? i almost can rule out the intake leak because i replaced the plug. i have done a search and maybe could it be the O2s. i have oofroad y pipe with simulators. my af gauge is actin kinda funny also. woul a dirty maf cause misfires after warm up or all the time? my car maek like 20%b power and stutters and pops then the ses light blinks and i knowthis means misfire . i am not driving it like this only around the block to see if the problem is solved. thank you for any input
#2
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Have you recently done any work to it? Changed the lid, maf, injectors, plugs or wires?
Your best bet, starting from the lid is to check all plug connections. Make sure they are seated right. I've forgotten to re-plug in my sensor on the lid and that caused no end of issues. The same with a fuel injector plug that wasn't seated properly.
From there check your spark plugs and wires for damage. Then your coils.
At that point check your o2's. Given it is misfiring as bad as you say, I'd almost garuntee that at least one of them is bad, and by now it must be fouled from excessive carbon due to the misfiring issue. Puull them both and check the tips (just try not to touch them). If one is carbon scored, it'll need replacing. If both look fine, swap them and see if the issue switches sides of the car (one sides exhaust pipes will heat faster) if so you have a bad o2. Replace, then have the SES turned off. Any autoparts chain can do it (NAPA, Autozone, O'Rielly's, pepboys).
If you can safely get it to one of those chains, it may do well to get what codes are being thrown. If it is an 03 code, see if it is cylindar specific. That'll point to the plug/wire/coil/injector. If it is an 01 (i believe) it'll say something like line 1 bank 1 or line 2 bank 1, it is an o2 sensor issue. Access to an OBD2 scanner will go a long way in helping you, and in my opinion is a very good purchase for any post '96 car.
Go through most of that and let us know where you stand
Your best bet, starting from the lid is to check all plug connections. Make sure they are seated right. I've forgotten to re-plug in my sensor on the lid and that caused no end of issues. The same with a fuel injector plug that wasn't seated properly.
From there check your spark plugs and wires for damage. Then your coils.
At that point check your o2's. Given it is misfiring as bad as you say, I'd almost garuntee that at least one of them is bad, and by now it must be fouled from excessive carbon due to the misfiring issue. Puull them both and check the tips (just try not to touch them). If one is carbon scored, it'll need replacing. If both look fine, swap them and see if the issue switches sides of the car (one sides exhaust pipes will heat faster) if so you have a bad o2. Replace, then have the SES turned off. Any autoparts chain can do it (NAPA, Autozone, O'Rielly's, pepboys).
If you can safely get it to one of those chains, it may do well to get what codes are being thrown. If it is an 03 code, see if it is cylindar specific. That'll point to the plug/wire/coil/injector. If it is an 01 (i believe) it'll say something like line 1 bank 1 or line 2 bank 1, it is an o2 sensor issue. Access to an OBD2 scanner will go a long way in helping you, and in my opinion is a very good purchase for any post '96 car.
Go through most of that and let us know where you stand
#3
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i have not done any work at all recently. the only thing i did was mess the plug in the top of the intake where the egr tube used to go.
i jsut got the car scanned at autozone and it is throwing a lot of codes. i know some will be from deleted egr cats and air pump. can anyone help me figure out where to start to solve this problem
here are the codes P0412 P0405 P0140 P0480 P0412 P0300 P0160 P0140
thanks
i jsut got the car scanned at autozone and it is throwing a lot of codes. i know some will be from deleted egr cats and air pump. can anyone help me figure out where to start to solve this problem
here are the codes P0412 P0405 P0140 P0480 P0412 P0300 P0160 P0140
thanks
#4
TECH Enthusiast
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the 405 and 412 are egr and air. You need to get those deleted out.
the 0300 is random misfire. That is more a symptom than a cause which is good in this case.
The 140 & 160 are your rear o2's. Do you have cats? Do you use the rear o2's? If not, a pair of o2 sims will be needed.
The 0480 is your fan probably do to your car not entering closed loop.
From all that I take it that the rear o2's are your problem. Pick up some rear o2 sims and it should clear up everything. Right now because of all the codes, your car is running in limp home mode, which is hurting it a lot.
the 0300 is random misfire. That is more a symptom than a cause which is good in this case.
The 140 & 160 are your rear o2's. Do you have cats? Do you use the rear o2's? If not, a pair of o2 sims will be needed.
The 0480 is your fan probably do to your car not entering closed loop.
From all that I take it that the rear o2's are your problem. Pick up some rear o2 sims and it should clear up everything. Right now because of all the codes, your car is running in limp home mode, which is hurting it a lot.