wholemilk

iTrader: (3)

so i picked up my car in feb of this year and it came with an aftermarket intake. today i had the guy at a dealership quote me for all the parts and stuff which was fine, then he told me it was highly recommended that i let them install it because they have to reprogram the mass air flow sensor. to my knowledge...you shouldnt have to right? so my question is, is the dealer jerking me around or do you actually have to reprogram that thing when you switch aftermarket intake back into factory?

ACEMAN

iTrader: (29)

WOW, never heard of a dealer doing this.

They are Jerking you around. At most, all you would have to do is reset the ECU or unhook the battery over night to reset the ECU.

What are they charging you for this reprogram of the mass air flow ??

Later
Todd

ACEMAN

iTrader: (29)

Here you go





1. Confirm that accelerator pedal is fully released, turn ignition switch “ON” and wait 3 seconds.

2. Repeat the following steps (a and b) procedures quickly five times within 5 seconds:
--a. Fully depress the accelerator pedal (HARD).
--b. Fully release the accelerator pedal.

3. Wait 7 seconds, fully depress the accelerator pedal and keep it for approx. 10 seconds until the CEL starts blinking.

4. Fully release the accelerator pedal (while the CEL is still blinking)

5. Wait about 10 seconds.

6. Fully depress the accelerator pedal and keep it for more than 10 seconds.

7. Fully release the accelerator pedal (The CEL light will continue to blink).

8. Turn ignition switch to “OFF” position and now you can start the car. The CEL light should be gone.


Later
Todd

sixsigmalarry

iTrader: (8)

I found using the built in stop watch in our car's worked great (just need to count the first 3 seconds on your own).

GOOD LUCK!

Chebosto

iTrader: (43)

HAHAH. he's pullin' your chain.

reprogram the MAF? no way man.

if anything, he just needs to reset the ECU, which is a button press on the ConsultII or any obd2 scanner..

Q45tech

The ecu has provision to fine tune [trim] the MAF and throttle position sensor in cabin.

Study your FSM it shows the correct proceedures to use with a Consult.

The MAF is calibrated to be accurate with oem filter and box.............changing things can result in a few % error especially at idle.

He [tech] may be correct and not even know it.

Wired 24/7

iTrader: (2)

wholemilk

iTrader: (3)

mmm thats what i thought, i worked at acura and i work at toyota now, and i've replaced MAF sensors before but never had to "reprogram" anything it was more of a plug and play then clear codes. hes trying to charge me 198 dollars for installing the airbox and programing the MAF sensor. i wasnt sure if nissan actually needed to do this so i figured i asked u guys. so i can save me 200 dollars now and just install the air box myself thanks everyone!

the procedure that aceman provided is great! i'll just follow that after install, but im prob going to clear the ecu from any codes and things first before that procedure. damn dealers...i work at one and i hate'em!

Ziggyrama

iTrader: (15)

The MAF sensor does not have to be reprogrammed. The ECU itself has lots of programming to interpret the output. The way MAF works is it has a tiny heater element inside it that is maintained at certain temp. As air passed by the element, it will cool the heater down. Knowing how much current is required to compensate for the cooling effect and knowing what temp the air is, you can calculate how much air is passing by. This is in essence how MAF works. The MAF sensor itself puts out a certain voltage to the ECU, which tells it how much air it is reading. I am not sure if the MAF sensor does the entire calculation or if the ECU reads the air temp separately and then based on MAF voltage calculates the air mass. I am pretty sure the MAF sensor does all the work and just pumps out the appropriate voltage to the ECU. The ECU has a map inside it that tells it that if voltage is 1v, that means that it has X amount of air. If it's 2V, it's Y.

Here's where things get hairy when you change the intake. One of the constants that are used in the calculation is the diameter of the intake. This is what MAF calibration is. Given the intake size, the MAF voltage represents certain amoutn of air. If you change the diameter of the intake, that calibration is off because if your diameter is larger, you'll have more air passing by than the ECU can account for. The size is assumed by the ECU. The ECU has this encoded in its programming and you can't change it without doing a reflash. The Tech may have been referring to that. However, if you never had the ECU programming changed, there's no need to change anything since the original calibration will be correct for the factory intake. Doing an ECU reset will not reset this value as it is stored in ROM, not RAM.

Generally, be careful with intakes on MAF based systems. Changing the size can significantly alter your fueling because the MAF calibration can be screwed up. The only way that this can work if the ECU has a corrective feedback loop in form of a oxygen sensor. All cars I can think of do that now hoever that loop is not always engaged. Depending on the type of the sensor and how the ECU is programmed, it may abandon the closed loop operation given a certain condition and rely on static maps and MAF readings to do fueling and timing. So, you have to understand the entire system before you start swapping parts left, right and sideways. Good ole "just throw an intake on" is not always the smart thing to do.

wholemilk

iTrader: (3)

yea, i dont know the history of the car to be honest with you, i bought the car at 37K miles and it came with the aftermarket intake. so i have no idea if the ECU had been reflash prior to it being traded in. I have a good feeling they wont even re calibrate my ecu, i think they might just clear any codes and readiness tests and send my car on its way. the decision i have to make is should i go install the stock air box myself or have them do it? (they ordered the box for me but it has not yet arrived) if i let them do it and the problem on my car still occurs i can go rip them a new *******, but if i install the stock intake myself i cant ***** to them if the problem is still present. Now it may seem wise to let them do it which i agree, in case of any come back problems they have to deal with it BUT they are charging me 198 dollars to do the install, now...i've worked for acura and i work for toyota now, and i know it does not take 2 hours to install an air box (they charge about 90 bucks an hr).

davidv

iTrader: (2)

Would a dealer jerk around a customer with expensive bogus maintenance? Don't be ridiculous.

gothchick

iTrader: (12)

Ooops. Messed this post up...

gothchick

iTrader: (12)

If your ecu has been reflashed you can 'probably' tell with a Cipher, Consult II, Digimoto, SnapOn Modius, etc... The 155 mph limiter will most likely be removed, rev limit set higher... Idle, TPS, AFR, & Timing adjusted... Most companies even put a sticker on the ECU after they reflash it.

I wouldn't ask the dealer to look for you though, cause if it has been reflashed, they will deny any future engine warranty work.

wholemilk

iTrader: (3)

yea, i'll check out the ecu at work. Im definitatly not saying anything to the dealer if it is the stock airbox install should be happening this coming saturday, i'll let everyone know if this fixes my problem.

wholemilk

iTrader: (3)

ok so i had theair box put in on tuesday of this week and so far no problems, but the problem happens at random so im not set on believing its fixed. the car drives fine, it feels the same but i know with factory parts in it, it cant go wrong. on a lighter note, my older brother has joined the VQ family!! he picked up his 2005 Infiniti G35 in white. its so sexy!!! me my bro and my friend with a mitsu evo will do a photo shoot soon, so pictures are coming

I just want to give a thanks to everyone who helped me with this problem as well, I appreciate the kindness from you guys