MAF Sensor issues - '93 Camry

[Pesca]

Hey all,

I've got a question regarding the MAF sensor on my '93 Camry Vienta (3vz-fe). Today I replaced the fuel filter and oxygen sensor and after reading about how cleaning the MAF sensor can improve performance I thought I'd check it out while I was at it.

My MAf sensor doesn't have two screws on the top to expose the sensor wire so i can clean it. Me being overly curious I unscrewed the side bit where the plug connects to it. I pulled it out slightly just to see what was what. When I started to feel a slight bit of resistance I put it back and screwed it back in, and then plugged the connector back in...figuring I'm better off leaving it alone.

When I go to start the car it won't start. The engine turns over but it won't start. Initially I thought it had something to do with the fuel filter..but as I was checking over everything I notice the car will actually start when I unplug the MAF sensor. Granted it won't stay running for long (sputters eventually then stalls) but at least it actually started. As soon as I plugged the MAF sensor cable back in and tried to restart, it went back to turning over but not actually starting.

So basically all I know now is that the MAF sensor seems to be the issue. I'm not sure if I stuffed something up by pulling the connection out (although I didn't pull hard on it or yank it away from the housing). Or maybe something needs to be cleaned. But as I said, there's no screws on the top of it so I can't get to any sensor wire to clean it. When I look in the MAF intake just pass the air filter case I can see a small plastic plug hanging down but that's it. I'm assuming the wire is inside of it but there's no way to get to it?

This is really driving me nuts, mainly because I just spent several hundred dollars getting a shift solenoid and ECU replaced and if the MAF is totally stuffed I know can't afford to fork out several hundred more dollars to replace that.

Below are the pics of my MAF just for reference.

Any help would be appreciated.

Edited January 30, 2010 by Loungefly

[sv21_ownR]

Hate to be the bearer of bad news but you have potentially stuffed your AFM(sounds like you did). See in the pic how there's a thin metal band that ends by those small rectangular blocks on the top? You're supposed to un-clip the metal band there(with a paperclip/screwdriver or something thin enough to fit there) to undo the connector. By loosening the screws, you have loosened some of the wiring inside. You're only chance of reviving this is to cut the rubber seal around the black cover on the top and see if you can re-connect the wires inside.

Other than that, it's a trip to the wreckers.

p.s. AFM's don't need cleaning. It's the TB, butterfly valve and IAC valve that should be cleaned.

Edited February 1, 2010 by sv21_ownR

[Hiro]

Yet another reason why the very big and important differences between MAFs and AFMs should be highlighted...

[Pesca]

Thanks for the replies. sv21_ownR, you were spot on. Turns out I did stuff the AFM (stupid me didn't realize from the outset that I was dealing with an AFM. not a MAF and that there are big differences). I ended up getting a used AFM from the local wrecker for $95. Runs great now. Lesson learned.

Thanks for the feedback guys. :)

[Whip Cracker]

Ah yes... have seen this happen a lot.

Rest assured, if you had a 1MZ engine, you'd be on the right track with the MAF :)

[andrey320]

This may be a little late for you Loungefly... but for anyone else that may encounter the same problem, here is what I did. I did the same exact thing as you on the same setup while changing my stock intake to an aftermarket WeaponR unit. Unscrewed instead of unclipping and pulled slightly. After finding this thread and beginning to search for a replacement part, I decided to see if I can fix it. I cut the sealant on the plastic cover, pried it up, and saw the three wires I pulled away from the circuit board. I've never soldered and did not have a soldering gun. Went to the store, bought one with some wire for 10 bucks and soldered it. Works just like it did before.

So the next person to break their part and find this thread, try fixing it before buying a new one.