2008 350z P0300 + P0420 + P0420/30. Help!
#1
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2008 350z P0300 + P0420 + P0420/30. Help!
I have no idea if I am posting this in the right section, but I need my fellow VQ owners to put their heads together and do a brother a solid. Bear with me here..
So this all happened after replacing the the dreaded oil galley gaskets on my HR (causes extremely low oil pressure) and doing a simple plug change.
My mods: Stillen g2 dual short ram intakes, 1320 performance resonated test pipes, ISR ( y-pipe and blast pipes), Z-speed performance CSC delete, stage 1 clutch & 17 pound lightweight flywheel
UPDATED: After the initial start up the car was running great in the garage, until I pulled up the street. The car tossed the dreaded P0300 code.. I began to diagnose.The car mainly throws the P0300 at idle. I also have a slight hesitation/jump at WOT when low in the rpm band (2500-3500)... It then pulls all the way to redline with no issues. Bank 1's fuel trim seems about right, varying between -7 and +7 %. Bank 2 at idle on the other hand skyrockets between 12% and 24%. Under load the trims seem to even out. The car counted 5 misfires on cylinder 1, 27 on cylinder 3, and about 100 on cylinder 5 (@ idle). Bank2 has no misfires. I changed the brand new oem Nissan plugs back to the Denso used plugs, no luck. I have unplugged the camshaft shaft positioning sensors, coil packs, maf's, and exhaust valve timing solenoids while the engine is running and everything seemed to check out. I have also searched for vacuum leaks and faulty wiring, no luck. By the grace of god can somebody please tell me something I may have overlooked? I know there are plenty of P0300 threads, but I feel like I have done plenty of research and digging to justify this thread. (THIS HAS BEEN GOING ON FOR 5 MONTHS)
Thank you in advance,
Bryce
So this all happened after replacing the the dreaded oil galley gaskets on my HR (causes extremely low oil pressure) and doing a simple plug change.
My mods: Stillen g2 dual short ram intakes, 1320 performance resonated test pipes, ISR ( y-pipe and blast pipes), Z-speed performance CSC delete, stage 1 clutch & 17 pound lightweight flywheel
UPDATED: After the initial start up the car was running great in the garage, until I pulled up the street. The car tossed the dreaded P0300 code.. I began to diagnose.The car mainly throws the P0300 at idle. I also have a slight hesitation/jump at WOT when low in the rpm band (2500-3500)... It then pulls all the way to redline with no issues. Bank 1's fuel trim seems about right, varying between -7 and +7 %. Bank 2 at idle on the other hand skyrockets between 12% and 24%. Under load the trims seem to even out. The car counted 5 misfires on cylinder 1, 27 on cylinder 3, and about 100 on cylinder 5 (@ idle). Bank2 has no misfires. I changed the brand new oem Nissan plugs back to the Denso used plugs, no luck. I have unplugged the camshaft shaft positioning sensors, coil packs, maf's, and exhaust valve timing solenoids while the engine is running and everything seemed to check out. I have also searched for vacuum leaks and faulty wiring, no luck. By the grace of god can somebody please tell me something I may have overlooked? I know there are plenty of P0300 threads, but I feel like I have done plenty of research and digging to justify this thread. (THIS HAS BEEN GOING ON FOR 5 MONTHS)
Thank you in advance,
Bryce
Last edited by @vq.bryce; 08-08-2018 at 07:10 PM.
#3
Registered User
Thread Starter
Its been months and I'm still having this issue. ( I finally took it to the dealer... complete waste of time) they told me what I already knew smh. Ive ran compression tests, smoke machined the vacuum system, replaced coil packs, checked injectors, etc. The only thing I could possibly think of, is that I screwed something up with the variable valve timing when I removed the timing cover. Do those soleinoids need to be clocked correctly or something ?
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