2001 Maxima SE (CODES! P0505,P0732,P0430)

[overdalimit]

Well here we go again! I just bought this 2001 Maxima SE at the auction today and it has the famous hunting idle! I get the car back to the shop and then run my scanner and got the following codes: P0430, P0732, P0505. The idle is high and fluctuating just like the other 40 million other peoples cars that has the same issue (good job Nissan). My main question is that sometimes the transmission starts off in second gear (or third) from the stop light and doesn't want to downshift to a lower gear when you floor it and or it slams into gear. Is this all tied into the IAC/TPS/ECM problem or is this something entirely different? Again, I don't know any personal issues with the car because I just bought it (Used Car Dealer) BUT, I did find a box on the back floor with the old MAF sensor so they must have changed that. I've done some research lastnight on these topics but just wanting someone to chime in right quick. I am looking at changing the IAC, the TPS, and the ECM..... Am I on the right track? I was also thinking of just getting my ECM repaired and that way I wouldn't have to get the dealer involved with the Key learn procedure.... Am I along the right track with my thoughts? Thanks fellas/ladies for your help. Car has 148,*** miles, w/ Automatic transmission.

[loystock]

P0430 is about Bank 2 3-way 'pre-cat' that is bad or related O2 sensors. Check to intake/exhaust leak. The 2 pre-cat could have failed if the previous owner delayed replacing a faulty MAF sensor for a long time (a rich fuel-air mixture can damage the 'cat' and O2 sensors if allowed to persist for a long time).

P505 refers to IACV - could be dirty and needs cleaning or failing and needs replacement. Pay close attention to this problem as a shorted IACV stepper motor can fry the ECU since the driver/amplifier for the IACV motor is inside the ECU. This may be expensive to repair if the ECU is damaged.

P0732 is about 2nd gear slip. This may be due to the other two problems, dirty transmission fluid or a failing transmission. Check the level and condition of the ATF. If dirty, perform multiple drain and refill as no decent shop will flush a transmission with over 80K miles unless a previous flush record is available.

Refer to the link below for additional info:

maxima-forum-i30-i35-forum.html