Brand new to this site. Facing expensive replacement of ECM in my '02 Maxima SE. Car passed state mechanical inspection, but threw P0327 code & failed emissions. Mechanic says knock sensor OK. Traced problem to ECM. Found voltage drop from ECM after running engine heats up. When engine cools, normal voltage returns. Mechanic says ECM needs to be replaced. He can get remanufactured for less $$ but is squeamish about checking all the settings. Says dealership is better equipped to handle that, but dealer won't install remanufactured. It's shaping up to be a $2100 bill. So frustrating because car won't pass emissions, but it's an electrical problem. Any feedback's appreciated. Thanks.

Best bet is probably going to be finding a used one. You should be able to get one for under $200 used.Here's a few listings on ebay:http://search.ebay.com/2002-ma...dZ300

Thanks, MOD. If I buy recycled / remanufactured ... should a dealer be willing to program it after I install? My regular mechanic assumed a dealer would not, would use only OEM part and charge $$. Also, why must dealer reprogram the ECM ... more than just NATS? Thanks again.

I completely forgot about the NATS...too used to my OBDI cars.

I'm not sure there...hopefully some of our 5th gen owners can chime in.My guess is that it'll vary by dealer as far as being willing to program non-OEM computers. I assume NATS is the reason for the program. Unless there were "patches" for the Maxima like there were for other early throttle-by-wire models.

I called a dealer to see if they would re-program an ECM that I install, and the service manager convinced me to bring it for a 2nd opinion. It was my regular mechanic who traced the problem to the ECM and said it needed replacing. But the dealer service mngr. said he'd never had to replace an ECM in 4+ years & would have his 20 yr+ master tech double-check the diagnosis. $80 per hour vs. $1100 for new ECM and re-program. Made the appointment. Good money after bad? We'll see.

Personally, I would just buy a junkyard ECU and have the NATS reprogrammed. If your dealership won't do it, find one that will. They'd be stupid not to since it's basically 100% profit

This may be a stupid question ... if I replace the ECM myself, the car will not start, correct? Will I need to have the car towed to dealer? Install the ECM in the dealer lot then push the car into a bay?Also, if anybody knows a Nissan garage/dealer within 50 miles of Portsmouth NH that is likely to reprogram for a fair price, please pass along the name. Thanks again.

It won't start until you have your keys matched to it.It is a pretty simple install. Certainly worth a try to pop it in yourself and then roll it into their bay. I'm not sure how they do the key encoding with a non-original ECU, though.