re: 2001 AE Maxima

1. I just replaced the whole Mass Air Flow unit (check engine light on). The dealer insisted I pay them $100 to update the ECU since they said that part had been re-engineered. 800 nissan 1 was unable or unwilling to provide me with that service bulletin- was I ripped off? It seemed to run fine after install without reset.

2. I get a very light vibration-like sensation, particularly over 50mph. I did a high tech dynamic balance; new rims/tires. I replaced a wheel bearing and a brake rotor. It is better but still there...just annoying. The struts are only 1 year old and suspension seems tight...any ideas? It's all stock.

 

1. Leave your battery disconnected for 36 hrs. It will reset the ECU. Or you can do the Learn procedure in the Stickies.

2. Vibration- I think we all have it. I've had it for 2 yrs. Inspect your tie rod ends.

 

reset is VERY diffirent from reflash (update). disconnecting the battery will not reflash to fix the problem

 

36 hours is not necessary....overnight is fine to reset ecu

it isn't necessary to go back for the reflash....if it drives fine, then leave it as is...if it's still stuttering, then the ecu has to get an updated program...so go back for the flash and cough up the $100

 

didnt have the reflash.. put the maf in myself,.. no problems, everything was/is fine ( think i unpluged the battery overnight too BTW)

 

ye that was a total rip off, changed MAF twice w/o problems, unless u have a problem its not needed. but hey live n learn.

try to reballance thw wheels. some shops do a crappy job sometimes.

 

The exact same thing happened to me!! I replaced my MAF just a little bit ago and the dealer said the check engine light might come on, and if it did, then bring it back to the dealer to reprogram the ECM. Little did i know that crap costed $90! So after the light came on I took it to them to turn it off, and right after some hard acceleration for highway merging the day after, that damn light was back on again. And they said to bring it back in and pay them another $90 just to see what the problem is. I said hell no. I took it to my mechanic around the corner, and he hooked this machine up to it, and said the problem was oxygen sensor #2 on bank #2 (does anyone know which one that is on a cali spec car by the way?). He reset the ECM, which turned the light off, and it has yet to come back on. The process took less than 5 minutes to diagnose the problem and turn the light off. He said the light might not even come back on, in which case there is no problem. Bottom line: Nissan told me that process takes an hour and costs $90. Reality: it took about 3 minutes and the mechanic didn't charge me a dime.

 

Also, does anybody know, will disconnecting the battery for 36 hours or overnight correct the problem of an airbag light constantly flashing?

 

I would hope not.. that usually means something's wrong.. I would figure out what's broke and fix it. Safety repairs are covered under lifelong warranty anyway.

wyche89: buy an OBDII reader.. pays for itself after a few times to the dealership.

 

i hope you didn't only have one side of the rotor. when replacing, always replace it in pairs, just like brake pads

 

I had my MAF replaced by my independent mechanis. He did not do a reflash, though he claims he rest the ecu. About three months after, the bad maf symptoms reapeared, cel and all. He said it was the mAF again and replaced it again for free, but I suspect it was b/c he did not re-flash,. It's been about two months now and no problems.

I also had the wheel vibration that started after getting new tires. I had all four replaced and re-balanced twice to no avail at a Tire Kingdom. The Infiniti dealer said they were defective. Ended up getting a refund, bought 4 new ones from the dealer (same price) and installed. They use a Hunter9000. Problem solved. Its all in the balancing.

 

jpd i think that may have just been a faulty maf you recieved. not reflashing the ecu should not have any effect on how long the maf lasts. had my maf replaced at the beginning of the summer. Did not get the reflash but it did improve the acceleration. the reflash is an update for the ecu of the fuel maps. supposedly updating might improve gas mileage slightly and it might give a little bit of a smoother accleration. do not think it is neccesary because the ecu will adjust itself to the best of its ability.

 

maybe you forgot the change the air filter? or over oiled K&N>>>>>>> bad air filter = MAF breathing bad air

 

Changing the MAF doesn't require updating the ECU UNLESS you are experiencing bad gas mileage after the install. RESETTING the ECU absolutely doesn't do anything unless you are clearing a faulty code and then the ECU will re-learn from the newly reapired sensor. You can continue to drive the car with the new MAF, the ECU will still read from it, but may alter and give you lower gas mileage. Taking it to the dealer and getting them to use the CONSULT, they will upgrade and download the new software into the ECU to adjust to the new MAF. The new software will then adjust to give you the better gas mileage. It's totally up to you what you decide if you want the upgrade or not. It's not necessary. If you still get a CEL from the MAF after the swap, then I would believe that the MAF is still bad or some type of connection to it is faulty somewhere.