maxirob

About 5 months ago just before I tore the intake down to replace the very leaky right bank rocker cover gasket she started stalling when idling, then bucking at higher rpm's. Progressively becoming more frequent and then finally...got P0100 MAF code. After suspecting a poor ground, broken connection in the wiring harness and having a P0130 (right bank o2 sensor-firewall side) popping up during this ordeal and reading tons of post about this on this site and others I finally found the definitive cause. On the MAF the 3 pin connector is soldered internally directly to pins coming off the circuit board-creating an electrical as well as a mechanical connection. Not a good design! When I took the MAF apart the pins looked connected but were cold solder connections at this point. I modified the connections with short wire leads resoldered and flipping the harness connector around - the engine is back to running rock solid! I suspect this is THE reason most 4 gen max's and I30's are exhibiting these symptoms and many have paid hundreds and/or thousands having mechanics chase down the cause. Hope this helps others.

mtnbikeskiparty

i too have a p0100 code and i tested the MAF and it was fine, did resistance test, backprobe voltage check, cleaned with MAF cleaner, cleaned throttle body, and everytime i reset ecu the code came back. finally bought a new ebay MAF and it seems to have fixed the bucking problem but the engine still doesn't run perfect and the p0100 code still shows up.

did you try backprobing your MAF and did it read correct values?

i also replaced all vacuum lines going into the maf area and I am now waiting on new air intake hoses to completely replace everything before the throttle body including a different aftermarket air filter (had stillen)

mtnbikeskiparty

I'm not quite sure what you are saying you did to the wiring connector? did you get rid of it and just solder the wires directly together at the MAF?

cashoit

He is saying (i think), the MAF has 3 pins on it that connect to the car harness. When he took the MAF apart, he noticed the 3 pins are soldered directly to the MAF circuit board. He used wire and resoldered those connections. and that seemed to solve his problem.

those ebay MAFs are usually hit or miss and not OEM. Autozone has reman MAF where another company resoldered OEM MAFs.

HIt the JU for a used MAF or AZ. I wd be leary with ebay MAFs. Or check the classifieds...someone always selling used MAF.

luke95gxe

iTrader: (4)

i had to resolder these cicled points and it solved my issue but make sure U RESEAL THE MAF i did not and condensation got in and it made the car feel like i was misfiring i had another maf laying around put it in and solved that issue also could have saved the trouble by RESEALING THE MAF with some silicon hope this pic helps

if you in the market for a used maf check out fallenones thread in the 4h gen classifed dudes got alot for sale

maxirob

Excellent Pic luke95gxe. I tried to take pictures of what I did but they turned out lousy. I unscrewed the wiring harness connector, soldered short lengths of insulated wire on and then flipped it 180 to get them out of the way, and then soldered to the pins coming off the PC board. The idea was to de-couple the mechanical connection. Let me tell you I cleaned, and cleaned, and checked vac lines, and everthing. What kept throwing me was I reached around and moved the wiring harness and thought that was the problem, the thing was I was moving the wedge shaped box in the processes and putting just the right angle of movement on the MAF housing to trigger the MAF's internal cold solder joint and kill the engine. It's been a week since I repaired it and it's still rock solid. And YES you must remove all the old silicone and reseal with new RTV.

luke95gxe

iTrader: (4)

thanks man i chased this problem for a long time it got real bad in the summer with the heat and all

maxirob

One more thing I discovered relatiing to resealing the cover back with silicone so its air tight. I noticed that after I removed the MAF assembly from the car I could press on the circuit board cover and hear air whistling in/out of the plenum. I discovered there is a tiny vent hole above and just off center on the TB side of the sensor vane going into the circuit board area, so I figured the circuit board enclosure HAD to be sealed or air could leak in and throw the sensor reading off. I even put a thin bead of silicone around the harness connector when I flipped it and screwed it back in. I could see that if there was a crack or air leak around the connector and/or cover, extra air could leak into the throttle chamber a wreak havoc on the sensors accuracy to the ECU.

Tyler89

maxirob

Yep sounds just like what mine was doing... The connections will LOOK just fine, but I suspect they all eventually fatigue and become cold soldered at some point. I can tell you I have not had a problem since I did my modification. Try this experiment with the car idling normally, apply some pressure on the air filter housing and she if engine stalls, stumbles, or dies. This will confirm the poor/cold/fatigued connections. Good luck and let me know how it goes. Also beware of those cheap oem MAF's out there. I tried one at one point and the engine ran sorta OK at above idle rpm's, but idle was lousy! I finally just returned it and took a hit on the shipping and re-stock fee, but it gave me the opportunity to fix my original and put it back in. It's still running rock solid.

defiance

iTrader: (1)

This is why all of our MAFs fail, its simple, vibration (bumps and potholes) slowly kill the MAFs and the original welds begin to deteriorate. In my 5 years of owning my 96 I have been thru 2 MAFs, and usually right after I hit a road imperfection on the highway the car would buck real quick and then return to normal.Eventually it gets worse and worse until you either have to re solder the 3 welds like Maxirob did or just buy another off the classifieds like I did. Re soldering it would be a more permanent solution depending on how its done though. However for around 40 bucks you can just buy a used one be good for another 10 to 50,000 miles :]

maxirob

To add to what [defiance] said, if you think about it the air cleaner housing is mounted to the chassis (albeit on rubber bushings) and the MAF housing is under constant stress as the engine vibrates and moves on it's mounts. I think as the engine mounts eventually wear out and allow more engine movement, this just places more stress on the MAF housing until those solder joints fatigue and cause issues.

cashoit

the reman MAF are simply old MAFs that have been resoldered and maybe a new wire element.

pwmaxgle

My 95 Maxima GLE has been having stalling, chugging and bucking problems for over a month but no codes what so ever.
I'm going to attempt resolder my original MAF as shown luke95gxe's pic above to see if that fixes my problem.

cashoit

yup give it a try

pwmaxgle

I bought a soldering tool kit from a local Radio Shack and re-soldered 6 points shown in luke95gxe's pic. My GLE ran about 200 miles with re-soldered MAF and so far performance has been rock solid!
Random stalling at idle, chugging and bucking at around 2000 rpm issues without CEL has not reproed for me so far. Hope my Maxima will continue to run rock solid with re-soldered original MAF.

I really appreciate .org members for sharing this MAF solution resources.
MAF issue was a very unique problem for me to to diagnose on my Maxima because I didn't have a single CEL code and all other mechanical areas looked good but that random stalling at idle, chugging and bucking around 2000 rpm problem drove me crazy...
Also purchased a used a MAF from .org classfied so I have a back up MAF for future MAF issues.

cashoit

no doubt man. Rock on!

signals

[i had to resolder these cicled points and it solved my issue but make sure U RESEAL THE MAF i did not and condensation got in and it made the car feel like i was misfiring i had another maf laying around put it in and solved that issue also could have saved the trouble by RESEALING THE MAF with some silicon hope this pic helps......]
i've 97 maxima that just gave P0100 code relating to MAF sensor. I have no stalling problems. Any one with ideas of cause and solutions? Thank you very much.
I have the code since recently disconnecting the battery and reconnecting it back. A few weeks back I cleaned the EGR guide tube, replaced the KS, changed ATF after replacing filter and cleaning drain pan, replaced fuel filter. It was working fine earlier P0350 & P0400 codes are gone. I believe these have nothing to do with P0100.
I love the forum with so many happy to help and knowledgeable people

catalinvint

Nice fix. I had the same problem. Went to the dealer and got slapped with a $500 answer for a new MAF.
Went to the junkyard and bought a MAF from a Maxima there for $40 and solved the issue .

komik

After reading this thread I decided to give it a try. I currently have a CEL for P0100 with only a few incidents of "bucking" prior to the CEL appearing. I went to the junkyard yesterday and picked up 1 complete and 2 partial MAF's ($40 for all three). I installed the complete one on the car last night. The light is still on but I only drove to work and back. Tonight I opened up the MAF I pulled off my car and added some redundant jumper wires in the hopes they will literally "bridge the gap" wherever any broken solder joints may exist. I resealed the top with black RTV and will let that dry overnight before I reinstall it on the car. *fingers crossed* Later I plan to take the plug off the one with the broken case and attach it to the one with the complete case and missing plug to have as a spare in case my new, but far from expert, solder joints fail.

Stock


Jumper Wires Added


MAF collection

edwardh1

how does toyota design to avoid these problems?

komik

After a week of the light staying on, I frankensteined the two partial MAFs together. This time I did a much better job of soldering the contacts. I added redundant wires and made sure they were secure and making good contact at both ends.

I'm happy to report that one week and 500-ish miles later... the CEL went away!