so i have been having these random misfires/backfires and hard starts for over a year now...i recently did a full 00vi swap (previously Mevi) which made it even worse...getting 14 miles to a gallon, car hesitating to accelerate, hard starts, CPS(cam) and Knock sensor and 02 sensor codes..even installed new injectors and spark plugs ...so i gave up on it and took it to my trusted mechanic...after a few hours of effing around and after 4 used CPSs we decided to buy a new one and found out it was cylinder 1 that was misfiring..we installed a new CPS and a KS. i had a couple 00vi rear coils sitting around so we pulled one out of cylinder 1 and replaced it with another used one but wrapped in electrical tape..cleaned out Crank Shaft position sensor (POS), tightened up bolts on 00vi for the vacuum leaks i had..
We started her up and bammm ... first click she fired right up.. we test drove it (did a couple WOTS) for abt good 30 miles now since this evening.. and everything seems to be fine.2 codes came back both 02 sensor codes

i dont know what was causing it but a new CPS, a cleaned CKPS (POS), and a coil wrapped in tape seems to have fixed the problem...

i am gonna keep driving this one( i have 2 maxima) for atleast a week and keep u guys updated if anything happens.

hope this all helps.

Talha

 

Interesting that you say you were replacing the sensors with used ones, that's what I've been doing. They ohm out properly so I figure how could they ALL be bad....but my problems continue.

 

yeah i even pulled one out of my other max and same thing.. i still dont understand that part

 

maybe it's not the part itself?

maybe a bad harness/chafed wire somewhere? just tossing ideas at you.

 

yeah i dont know what exactly was it.. but car is running like a champ