Mass Air Flow Sensor - Meter Box

[lexus082]

Recently I had to replace my mass air flow sensor. My car was running rough and sometimes would stall while idling. They told me I needed to replace the MAF sensor. When I removed the old one I found a few pieces of dried up leaves and a small feather that were stuck against the outside of the honeycombs. It wasn't a lot of debree but nothing really should get back that far with the air filter in place. Would a few small leaves and a small feather stuck on the honeycomb part of the MAF assembly cause the unit to operate incorrectly. Is it more likely to be one or the other? I checked the resistance between what is specified in the Lexus repair manual and it said 2-3k ohms @ 68*F and it was around 2.2 ohms? Could it just be the dirt wasn't a whole lot, but I dont know how sensitve the sensor is. Any suggestions/comments would be great?

[lexus082]

Recently, I had to replace my mass air flow sensor.  My car was running rough and sometimes would stall while idling.  Toyota told me I needed to replace the MAF sensor.  When I removed the old one I found a few pieces of dried up leaves and a small feather that were stuck against the outside of the honeycombs.  It wasn't a lot of debree but nothing really should get back that far with the air filter in place.  Would a few small leaves and a small feather stuck on the honeycomb part of the MAF assembly cause the unit to operate incorrectly.  Leaves or bad sensor, is it more likely to be one or the other?  I checked the resistance between what is specified in the Lexus repair manual and it said 2-3k ohms @ 68*F and it was around 2.2 ohms?  Could it just be the dirt, it wasn't alot, but I dont know how sensitive the MAF sensor is. Any suggestions/comments would be great?

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[SKperformance]

Did you try cleaning the maf before replacing it?

If not do you still have it to try and clean it and reinstall.

Usually it only takes a light cleaning to return to normal.

[lexus082]

Did you try cleaning the maf before replacing it?

If not do you still have it to try and clean it and reinstall.

Usually it only takes a light cleaning to return to normal.

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No, I replaced it with another used one. I still have the original MAF sensor though, what would you recommend to clean it? Is there anything else I can do to clean it rather than just removing the pieces of leaves from the honeycomb part. Should I spray a cleaner on it, etc? Thanks

[SKperformance]

To clean a MAF basically

spray throttle body cleaner

wash off with small amounts of brake kleen ( non clorinated)

then compressed air.

You really have nothign to lose.

[lexus082]

To clean a MAF basically

spray throttle body cleaner

wash off with small amounts of brake kleen ( non clorinated)

then compressed air.

You really have nothign to lose.

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Thanks for following up on this thread. One last question, if say you checked the resistance and it was within lexus repair book specs. would you pretty much come to the conclusion that it's just dirty and needs to be cleaned throughly. Or is there still a chance that the sensor could have gone bad, but still the ohm's would remain within lexus specs. Thanks again!

[SKperformance]

If the resistance is spot on then it probably is just dirty as the reading is the resistance of the filament which is cooled by passing air which increases voltage over it thus letting the ecu know the injested volume

[Moony400]

Lexus 082, do you still have the old MAF? Have you cleaned it and put it back to see if it work? I'm having the same problem that only seem to get worst. First I would only get the check engine with trac off, but the car drives fine. I replace the right back O2 sensor, still getting check engine light. I then cleaned the MAF, which didn't look dirty at all when I took it out, but cleaned it anyways. I also clenad the plug for it with those fast drying electrical plug cleaners. Now my car mis-fire and constantly stall as I'm trying back out of my drive way.

Any suggestion?

MoonySC400

[lexus082]

Lexus 082, do you still have the old MAF?  Have you cleaned it and put it back to see if it work?  I'm having the same problem that only seem to get worst.  First I would only get the check engine with trac off, but the car drives fine.  I replace the right back O2 sensor, still getting check engine light.  I then cleaned the MAF, which didn't look dirty at all when I took it out, but cleaned it anyways.  I also clenad the plug for it with those fast drying electrical plug cleaners.  Now my car mis-fire and constantly stall as I'm trying back out of my drive way.

Any suggestion?

MoonySC400

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I cleaned the old one and it still didn't work correctly. So it must have been more than just dirty. It could be a bad MAF sensor. My engine would rev really low at stop lights like it was about to stall out and sometimes it would. I didn't have any problems other than at idle speed with it acting up. Before assuming that it is one thing you could just have the light check engine light checked out at a toyota dealership. I went to the toyota dealership and they diagnosed the check engine light for only $35.00. and told me it was my MAF sensor. Thats what I would recommend you do with that sort of problem, due to the fact that there are several possibilities for it to be acting up in the way you described. That way they can most likely tell you what it is exactly so you know what to fix/replace without having to spend extra money on trying to repair or replacing something that is working correctly. If it is your MAF sensor then I would recommend checking ebay for the sensor and buy one used that is still in good shape from a seller you can trust. I remember toyota wanted $1100 for the sensor. I can get it discounted new for around $800, but I still only paid $130 for it used from e-bay and it has solved my problem. Hopefully it will last for a while.

[Moony400]

Lexus082, Thanks for the advise. Looks like thats what I'm going to have to do. I took a reading of the MAF as describe somewhere in this forum, where it should read between 2-3 k OHM and mine was reading at 2.25 kOHM. So looks like it withing specs, but still got problem. One thing I tried was just unplugging the MAF connector and start up the engine and it starts fine and was idling fine. I drove around for a bit and nothing weird seems to happen. The car warmed up fine and it just drives fine. WEIRED. I'll post a result after taking it in for a diagnostic.

Thanks,

MoonySC400

[lexus082]

Lexus082, Thanks for the advise.  Looks like thats what I'm going to have to do.  I took a reading of the MAF as describe somewhere in this forum, where it should read between 2-3 k OHM and mine was reading at 2.25 kOHM.  So looks like it withing specs, but still got problem.  One thing I tried was just unplugging the MAF connector and start up the engine and it starts fine and was idling fine.  I drove around for a bit and nothing weird seems to happen.  The car warmed up fine and it just drives fine.  WEIRED.  I'll post a result after taking it in for a diagnostic.

Thanks,

MoonySC400

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Mine registered fine also when I tested the ohms, but something wasn't right with it. Having it diagnosed will probably be the lesser headache. Good luck, hopefully its nothing too major or expensive. If you need new parts I would recommend www.luxurymods.com, they can save you some money.