huge problem. three cylinders not firing
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Joined: Nov 2010
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From: hawaii
Followed this thread and have a suggestion (didn't see this discussed). I had a similar problem with two cylinders. Your lucky since the engine should not run with 3 bad mis-firing cyclinders. It can't be the timing since some of the cylinders are firing and the. A scope is the best tool for checking, but a VOM will work. With the engine running, disconnect each wire from the suspect injector and check for a pulse. Next check the voltage to the coil packs. If the ECU was disturbed at some time, it could be the connections out of the ECU or piggyback if you are using one. Hope this helps.
The three cylinders misfiring are all of bank 1, my friend from nissan already ran the consult II and flow tested the injectors. And they checked good.
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From: hawaii
also checked the entire engine harness for breaks which took me two full days. and even swapped the ecm which made a pretty deep hole in my pocket with no success. had my nissan tech reprogram the ecu to the key and vehicle an i got the same exact p0300 dtc.....
Thread Starter
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Joined: Nov 2010
Posts: 108
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From: hawaii
Followed this thread and have a suggestion (didn't see this discussed). I had a similar problem with two cylinders. Your lucky since the engine should not run with 3 bad mis-firing cyclinders. It can't be the timing since some of the cylinders are firing and the. A scope is the best tool for checking, but a VOM will work. With the engine running, disconnect each wire from the suspect injector and check for a pulse. Next check the voltage to the coil packs. If the ECU was disturbed at some time, it could be the connections out of the ECU or piggyback if you are using one. Hope this helps.
Also what was the cause of you problem and how did you fix it? What type of injectors are you running, assuming your injectors went bad since you're suggesting to check the injectors.
just saw this thread..... I have a similar problem now if you look at my thread. My only happened a couple days ago but have not had time to really diagnose like you. If you figured out any fix please pm me.. thanks .
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Joined: Apr 2010
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From: Maryland
I have DeatschWerks injectors and found that one of them failed to inject when installed on the car, but worked fine on the bench. Sent all them back and got a replacement that was matched to the others. I found this by removing the plenum and placing a paper towel beneath each injector and turned the engine over. The paper towel was wet under the good injectors but was dry as a bone under the failed one. be carefull not to let the paper towel get into the valves. I got pretty quick at removing and installing the plenum. I also confirmed the failed injector by swapping all the injectors between banks. This moved the problem to the other bank. In my case, I could not smell fuel from the exhaust on that bank which led me to this check.
If you look back at my old post from months ago, and I am suprised you did not do what I said. Take the intake manifold off the car. Pull the fuel rails out with the injectors still in them. Have someone hold the fuel rails and watch the injectors while you crank the car. Also pull the coil packs out and crank the car and look for spark, spark plug in is easier. This checking for spark is explained with pictures in the FSM.
On another thought my stupid pos nissan has a Multiple missfire at partial throttle and runs perfect at wot. I think I have a vacum leak from last time I took the intake manifold off but im not sure considering it took months to show up. Either that or its a bad battery, was cranking really slow. Now won't hold a charge. No time to screw with it. I am thinking the battery since its from 2006...
I acutally cut the the wires from the bad injector and ran a jumper wire to the ecu just to make sure it wasnt the wire.
On another thought my stupid pos nissan has a Multiple missfire at partial throttle and runs perfect at wot. I think I have a vacum leak from last time I took the intake manifold off but im not sure considering it took months to show up. Either that or its a bad battery, was cranking really slow. Now won't hold a charge. No time to screw with it. I am thinking the battery since its from 2006...
I acutally cut the the wires from the bad injector and ran a jumper wire to the ecu just to make sure it wasnt the wire.
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From: hawaii
i could be going crazy here, but i think i need to check the base timing and remove the timing chain cover. Im thinking the chain jumped a tooth on only the drivers bank cam gear. is this to far-fetched? LMK if Im getting to ridiculous with my troubleshooting.
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From: hawaii
im actually deployed right now. i get back in january. so its gonna be a while till i can rip into my engine. in the mean time i'm just researching all the replacement parts/seals ill need. I might as well change the chains if im in there. Im hoping i actually find something wrong this time.
I just got my catalytic converters replace. Here was my problem.
https://my350z.com/forum/maintenance...eshooting.html
https://my350z.com/forum/maintenance...eshooting.html
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From: Florida
Problem Solved ? Any Updates ?
im having this same issue with my 06 350z ive done plugs , injectors , coil packs , cleaned maf sensor , cleaned my fuel rail , compression test was good (150) , cylinders 4 and 6 arent firing and 2 is running weak , i dont have any cats , could it be an internal vacuum leak or even something with the exhuast since its starts on the same side as bank 2 which is where my misfires are ?
im having this same issue with my 06 350z ive done plugs , injectors , coil packs , cleaned maf sensor , cleaned my fuel rail , compression test was good (150) , cylinders 4 and 6 arent firing and 2 is running weak , i dont have any cats , could it be an internal vacuum leak or even something with the exhuast since its starts on the same side as bank 2 which is where my misfires are ?
im having this same issue with my 06 350z ive done plugs , injectors , coil packs , cleaned maf sensor , cleaned my fuel rail , compression test was good (150) , cylinders 4 and 6 arent firing and 2 is running weak , i dont have any cats , could it be an internal vacuum leak or even something with the exhuast since its starts on the same side as bank 2 which is where my misfires are ?
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Joined: May 2022
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From: Copacabana
this problem did not happen post spark plug/ coil checkout. so i dont think they are switched. at least one of the cylinders would be firing anyways, if that was the case. if you read back i checked which cylinders were firing by pulling the coils out while the car was running. all the drivers side cylinders had no effect when i pulled the coils. and all the passenger side coils made a noticeable difference when pulling them. i also switched the coils to see if the same thing happened and it did. so all the driver side cylinders are non-contributing cylinders.