Hi everyone. I wasn't totally sure where to post this question, so hopefully this is an ok spot. I recently went to check on the condition of the air filter in my '91 4runner. This truck has been great. I have had no problems with it. I purchased it about two months ago and figured it was about time to take a look around the truck. I unclipped the housing around the filter and removed the filter. It was moderately dirty but not bad so I cleaned it with a vacuum and replaced it. I was then curious to see how easy it would be to remove the MAF sensor for cleaning. I have read that regular cleaning of the MAF can greatly help the performance of the vehicle. I removed the two screws on either side of the wire connector thinking that was how it was held in place. I quickly realized this was not the right thing to do, and put everything back. I left everything else alone. Later in the day, I went to start the truck. Nothing. It cranks and catches, but dies after a second. This has never happened. It usually starts right up. I'm hoping I didn't damage anything relating to the MAF sensor. But I believe it should start even without the sensor plugged in. (I unplugged it the right way to see.) The only other thing I can think of is bad gas. I put in some drygas water remover stuff, in hopes it would work. Its been a few hours now and it still wont run. ANY suggestions or tips would be VERY helpful. This is my only vehicle and I need to figure this out fast. Thanks!

 

how good are u with a soldering gun?? when u took out the 2 screws how far did u pull that piece out? if u did like me u pulled some piece off and now are going to have to resolder or replace that part. cut the silicone on the top part and remove that and look at it, u will find that u probe broke free something, after u solider it then u can put the cap back on and reseal it. it worked for me,

 

If you indeed did break some of them teeny tiny connections in there, not good.....go to the junkyard and look online for a discount MAF

 

Did you disconnect any of the vacuum hoses when you were cleaning the air box out? look for any hoses that may have gotten disconnected

 

Oh boy, this again. Will they ever learn? Sorry to have to say this, but you just screwed yourself, pun intended. It's quite a bit worse than having to reconnect a hose or two I'm afraid.

So...

For starters, your vehicle doesn't have a MAF. It has an AFM. And you should NEVER try and take apart/disassemble an AFM unless you thoroughly understand how it's constructed and how it functions. And absolutely, under no circumstances, should you EVER remove those 2 screws! Let alone tug on the connector after doing so.

Next, you messed up BIG TIME by removing those screws and pulling on the connector. Now you will have to take a crash course in AFM theory and operation. Or go buy a new/used one to replace it. Because fixing it will require removing the cap on top of it, and reconnecting the wires which you've inadvertantly disconnected. Depending on the extent of the damage, you may also need to resolder some connections too.

There are many threads on this subject, and how to remedy it. But the one that came up recently was one of the better ones(with quality pics and detailed instructions).

Here ya go. https://www.yotatech.com/forums/f116...nation-226336/

 

Thanks guys. I was really hoping that I wouldn't have to go in and solder stuff in there. I really didn't touch anything, but I guess those pieces are REALLY delicate. The link was very helpful. Thank you. One more question though. I have searched for the MAF or AFM part for the '91 truck and gotten results for a few from a '94. Does anyone know if this will fit my year truck? It would be much easier to pick up one of these than to try and fix the one I have. Thanks again!

 

hey, don't feel bad, I did EXACTLY the same thing a few years ago... you must replace it or pop the plastic cover and put it back how it was, there's a few contacts in there that must get put back in their respective places... surprised yours even started...

i bought an A1 cardone crap replacement and it's fine (for a whopping $275, ouch), but I put my old one back together and cleaned the little plastic nubbin inside the air chamber (carefully) and she works fine now. big oops.

pretty sure the '94 will work, they put those VAFM's on just about everything... saw one in a little ricer yota today at o'reilly's...

best o' luck, let us know if you can put it back together or not. make sure to use some sensor safe sealant if you rebuild that thing, and the insides are delicate for sure.

 

Thanks again! I located a used potential replacement part at a salvage yard nearby. I'll probably replace the whole thing with that one, but I'm going to open up the one I have just to see if I can fix it. Which brings me to another question! What would be sensor safe sealant? Thanks again for all of your help. I'm learning a lot about this truck in the process. While its frustrating, its definitely good stuff to know.

 

i just used black rtv sealant to close mine up.