MAF sensor - can y'all tell me where

this sensor is located at on the '97 3.2L, or better yet, show me a picture of where it's located.

I'm guessing I can clean it with some electronical spray cleaner/Q-tips??

I don't know what else this same P0401 (insufficient EGR flow) that keeps popping up can be from. Thought for sure it was resolved, as it went off for a good 2 - 3 weeks.

I have cleaned the EGR twice, replaced all 4 O2 sensors (this DID make a BIG improvement in gas mileage), air filter is good. But I have never cleaned the MAF sensor before.

What causes this to dirty, BTW?

It may be possible that you need a new EGR valve or something involving the EGR system. Especially if you cleaned it that many times and well.

Isn't the MAF located somewhere on the ductwork for the intake? I believe mine is right after the air filter.

marc

Yup. Right next to the air filter housing. There is a harness plugged into it. I've cleaned the MAF on my VW Jetta 2.0L (ribbon type MAF), and in a Ford Crown Vic with a V8 (filament type MAF). I don't know what kind is in the Rodeo. I guess I ought to go ahead and clean it, too. But I wouldn't touch it at all. I would just pour some denatured alcohol over it, or put it in a baggie with some alcohol and swish it around. Air dry and put it back. In the VW, the cranckcase breather dumps into the intake very close to the MAF, coating it with oily residue. Other intakes aren't set up so stupidly, but the MAF can still pick up some grime.

I read a good tech report about how grime on the MAF can make the engine think it is at altitude, and then the computer adjusts to a richer mixture. Stuttering and hesitation are some symptoms of a failing or dirty MAF.

Let me know what you find!

The MAF sensor is the big'ol assembly clamped (w/ hose clamps) inline on the clean air tube between the airfilter box and the throttle body. It's usually clamped inline right near the air filter box. Here's a pic of a newer one: http://cgi.ebay.com/ebaymotors/LKQ-Isuzu-Rodeo-Amigo-Trooper-Mass-Air-Flow-Sensor-MAF_W0QQcmdZViewItemQQcategoryZ38634QQitemZ8046643 895QQrdZ1QQsspagenameZWDVW
The denatured alcohol flush sounds like a good plan to me!
G/luck
Joel

Ok, the little black square attachment, off to the side - this is the harness? Do I need to remove this to clean the MAF or is it permanently attached?

Ok, so it's located where I thought it was, and obviously I need to unbolt both ends of the intake hose - and I understand the MAF is 2 little wires, but do I need to undue the 4 bolts just below the circular screen (like in the picture)? Or IS this circular area, before the 4 bolts and the harness, part of the actual area that I clean??

Sorry guys, I've never cleaned one before. Just want to make sure before I go submerging harnesses and parts that shouldn't be submerged.

Hey RF,
The MAF sensor uses two small wires, one is the hot wire and the other a precision resistor. The hot wire in particular tends to collect microscopic pollen and other debris which actually "burns" onto the surface.
You should probably remove your red battery cable before removing the MAF. You will need to remove it for 15 min. or so before reinstalling the MAF anyway to clear out the history (codes).
The only thing you should use to clean your MAF is ELECTRICAL CONTACT CLEANER. No carb cleaner, no brake cleaner, no rubbing alcohol, and no Q-Tips.
You shouldn't need to remove the screen.. If you can see the small wires gently spray them with a series of short blasts of cleaner. If the wires are inside of a small inlet tube, spray into the mouth of the tube and let it run out the back (screen side). If you have to spray it into the tube make sure to give it time to completely dry before re-installing.
My dealership tried to sell me a new MAf after pulling the codes. I followed the above procedure, had Autozone pull the codes, and what do you know... no problems. It was just dirty.

I dont thing I would submerge the MAF in anything. Just clean it the way bishop described. I wiped out the MAF on my mitsu (ok, its a completely different style, honeycomb type) by cleaning it. Odd thing was that it would work fine unless the humidity got over 35%, then the truck would start kickin and buckin. Luckily I found a junk yard with one and since it was snowing that day the guy felt sorry for me and I got it for $20, new one was over $400.

Now that I think of it. My brothers escort (car, not lady) was throwing EGR codes at one time. The car didnt even have an EGR. Turned out to be a dirty MAF. It has the 2 wire style too. Just sprayed all the junk off of them with brake cleaner (ford mechanics idea), dried with some compressed air, and it was good to go. No more CEL.

It sounds like folks have had success with spraying from a can, but I have heard stories of MAF filaments breaking when sprayed.

..The only thing you should use to clean your MAF is ELECTRICAL CONTACT CLEANER. No carb cleaner, no brake cleaner, no rubbing alcohol, and no Q-Tips..

This might work too: http://www.crcindustries.com/auto/content/prod_detail.aspx?PN=05110&S=Y

Joel

Ok, I'll tackle this tomorrow. When I put the air intake back together, do I need to do anything to the end peices to make them seal good?

I've heard of some people smearing a drop of oil around the ends for a good seal, but I'm not so sure this is wise??

I was just looking at my MAF a couple of days ago. I am not sure I'd want to touch it. The wires look real fragile. Be careful.

marc

I was just looking at my MAF a couple of days ago. I am not sure I'd want to touch it. The wires look real fragile. Be careful.

marc

That's what I'm talking about!

Well, after tightening up the alternator and the belt, the CEL went off immediately upon restarting the truck. Hasn't come back on, gonna take the kiddos for a drive to Estes Park tomorrow, we'll see if it comes back on.

Not gonna mess it with at this point, if it comes on again, I'll take it out to see how nasty it looks before deciding to clean it for sure.