Nissan Maxima 1996 Mass Air Flow Sensor

sensors
#1

Well, my 1996 Maxima threw a P0100, which the manual says is a faulty mass air flow sensor. It has shown symptoms; hesitation, bad shifts, misfiring, etc.



The stock MAF sensor for this thing is $500. It takes about 20 minutes to swap out. It’s the $500 part that gets me.



I see some on eBay for about $100. If I change it, can anyone attest to the quality of these things? Am I likely to be changing it again in 3 weeks?



Also, I’m running a K&N. I read now that some are saying having an oil source that close to the MAF sensor will ruin it every time. I don’t know that I believe that. Opinions?



Lastly, can I clean the MAF I have and continue on my way?

#2
  1. You get what you pay for
  2. The code only means that your computer isn’t seeing what it expects from the MAF. This could be due to a faulty MAF OR SOMETHING ELSE. If you replace the MAF without more diagnosis, I would call that “throwing parts at the problem” - might work, might not.
#3

Thanks for your reply.

I took it apart last night (10 minutes), and sprayed in some “CRC Mass Air Flow Sensor Cleaner”. That cost $7.53. Basically, for anyone who wants to try this:

  1. When you take it out, DO NOT touch the film. It’s hard to do, because it looks like a toy. Well, that “toy” is worth $500, and if you touch it, you’ll break it.

  2. The fluid I got smells like tolulene in a spray can. In other words, I payed $7.53 for probably $.10 worth of chemicals. Sigh. Oh well.

  3. On the Maxima, spray TOWARDS the screen. You WILL have crud on that screen, and you do NOT want that on the film. This is a one-way operation; you’ll see what I mean when you take it out.

I think my car’s running better. We’ll see. But this is a better first option than, “Oh, shoot, how much does that guy on the internet want for THIS part?”. It was $500 at the dealer, $300 at Rock, or $100 on eBay vs “Let’s give the overpriced tolulene a chance.”

Crossing my fingers.

I also hit the sensor’s plugs and sockets with electronic cleaner.

#4

My fix to the MAF did not work.

One more note: About a week before this started happening, I managed to hit a flooded portion of roadway, on I-5… The car was going sideways on I-5 at about 45-50, and I felt lucky I didn’t hit anything. I was completely whited-out; could not see a thing (but I kept my foot lightly on the throttle and steered into the skid, which I’m sure helped).

Is there a chance the engine sucked in a small amount of water (not enough to cause hydrolock in any cylinder) that was large enough to damage the MAF? Because of the amount of time between my near-spinout and the MAF problems, I didn’t make the connection, but it seems possible that a small amount of water got into the electronics and is now causing a sporadic malfunction… Which means I still need to replace the MAF…

#5

Use the repair manual to check / test the MAF?
Does your doctor treat illnesses only from the symptoms? Does s/he perform examinations, and tests, before s/he makes a diagnosis? Many times, you would be dismayed if s/he didn’t.
The same approach your doctor uses, is the approach you need to use on your car. The similarities, of techniques, aren’t that different. And, think of the money you could save in wrongly changed parts! Hundred$.

#6

Some MAF’s can be saved by cleaning them. I would check at the local parts store to see if they have a less expensive MAF if cleaning does not work. (Note: as bobc indicated, it may not be the MAF, but in this case I believe it is)

Those K&N filters must have been designed by the MAF manufacture’s association. They kill more MAFs than anything else. If you oil them very carefully and not leave even a tinny but of excess oil, they likely will not damage the MAF, but it only takes on mistake. For stock engines they don’t do anything for you other than not filtering as well as a standard filter and killing off a number of MAFs.

#7

There is a procedure to diagnosis it, and they all end with “Replace MAF Sensor”. The $189 rebuilt one I ended up putting in has eliminated the glitching and the CEL. Believe it or not, it does run better.

Yeah, I think I’m going to get rid of the K&N. Back to $8 Frams.

A little history: Nissan used “surface-mount resistors” on a number of components. They used it in the speedometers and stereos, and I suspect they used some in this MAF sensor as well. Well, the resistors they chose are prone to failure. A high percentage of Nissans from this era end up with speedo and stereo and MAF sensor replacements, and I think the failure has a common cause: surface-mount resistors.

That’s my theory, anyway. I know it’s true with the stereos, and I suspect it’s true with other electronic components. On the rebuilt one I bought, you could see they took off a cover plate, and re-attached it with clear silicon. I think they’re after parts under that cover. It looks like they didn’t touch the hot wire itself.

Here’s a link to the stereo problem:

http://forums.maxima.org/audio-electronics/213946-bose-led-display-96-gle.html

(Personally, I see no reason to fix these units. It makes more sense to replace them, which is what I did with mine.)

#8

So, the MAF sensing wire, being contaminated was, apparently part of the problem. I don’t know about the surface-mount resistors. You could have removed the plate on the old MAF for a look-see; then, you would know.
You say you did the tests on the MAF. Did you do these?: http://www.autozone.com/shopping/repairGuide.htm?pageId=0900c15280076307

As from your search, it adds much more to our knowledge to learn why something failed, rather than, only, what failed.

#9

That’s more-or-less the procedure outlined in the shop manual (which I own) and in AllData (to which I subscribe). I did not follow it, and here’s why: The component was glitching. The engine would run great almost all the time, and then it would stall. At freeway speeds, the engine would resume operation, so it wasn’t usually a big deal. It became a concern when I’d pull out of a parking lot, with traffic approaching; I was never sure if it would stall during a move like that, and when it was close to idling-speeds, I’d have to restart. At freeway speeds, the fuel would cut off, but then resume before the revs had fallen 1,000 rpm or so. Invariably, the CEL would then come on with a P0100 (MAF Sensor).

Thank you for pointing me to this resource, though.

Yeah, I didn’t want to cut into the original MAFS because I wanted to recover the $32 core charge. Someone else had already done the engineering, and this part is easy enough to replace. I simply don’t have the expertise to troubleshoot at the board level. Curiousity killed the cat. Wasn’t worth it.

Because the component was glitching, I suspect following the test procedure would have shown the component was fine, unless I happened to catch it at exactly the right time. I think I got this one right.