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mass ar flow problem afrer cleaning

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Old Sep 29, 2009 | 06:38 PM
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Default mass ar flow problem afrer cleaning

just an hour ago i decided to clean my maf sensor so i took the three little screws out and cleaned it with a q tip , plugged it back in and started the car it seems to idle ok till i rev it ,,,it revs up and then drops alot almost to the point of cutting off, i have no cel light should i let it run to adjust itself or do i need a new maf sensor where can i get one from , autozone , how much would it cost from lexus dealer????
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Old Sep 29, 2009 | 06:54 PM
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Originally Posted by lslover92
just an hour ago i decided to clean my maf sensor so i took the three little screws out and cleaned it with a q tip , plugged it back in and started the car it seems to idle ok till i rev it ,,,it revs up and then drops alot almost to the point of cutting off, i have no cel light should i let it run to adjust itself or do i need a new maf sensor where can i get one from , autozone , how much would it cost from lexus dealer????
You need to use a spray can of CRC's MAF Cleaner on the MAF (available at Autozone or PepBoys). You aren't supposed to touch the fine mesh screen in there at all. I don't know if you've gone any damage by touching it, but I'd get the MAF cleaner, follow the can directions and hope for the best. Take the whole MAF (AFS as others call it) right out of the car. Let it air dry for an hour or so before re-installing and starting the car. Even then it will most likely run rough for five or ten minutes and the engine light will come on for a while but will eventually go out. You might also want to remove the ECU fuse and reinstall it before starting the car.

Good luck with it...

Jim
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Old Sep 29, 2009 | 07:02 PM
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I just reread your post about the three screws... Did you take apart the black electronic box? That's not how you clean the MAF. To clean the MAF you clean the fine mesh screen inside with the cleaner. Not supposed to mess with the black box!! Hopefully you didn't do permanent damage. An OEM new one is close to a grand I believe. Junk yard or ebay would be your best hope.
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Old Sep 29, 2009 | 08:37 PM
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damn , i just took those srews out and then cleaned that plastic falte tube part of that black box when i put it back in and started it the rpms were jumping up and down up and down , im not sure if its doing that because its damaged or becuase its not 100 percent dry , ill try again in the morning then go from there
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Old Sep 30, 2009 | 01:31 AM
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Originally Posted by lslover92
damn , i just took those srews out and then cleaned that plastic falte tube part of that black box when i put it back in and started it the rpms were jumping up and down up and down , im not sure if its doing that because its damaged or becuase its not 100 percent dry , ill try again in the morning then go from there
Yea, you're not supposed to touch it physically with ANYTHING. Even the CFC MAF cleaner spray stuff says not to touch the tip of the sprayer to the sensor (the lil black stick).

If only air is supposed to be hitting that probe, you may have damaged it as you used something physical with pressure. Junkyard is your best bet, and you only need that black probe like thing you took out. Everything else is extraneous.
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Old Sep 30, 2009 | 01:34 PM
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Never ever EVER clean a Karman Vortex MAF. To clean it = to kill it.

You can go into the box and replace the damaged ribbon of metal with a piece of foil, but often it won't run quite right again.
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Old Sep 30, 2009 | 02:23 PM
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i found one on ebay i am going to buy, do i have to do anything reseting on the ecu i have to do , or do i just instal the new one and plug it up ,
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Old Sep 30, 2009 | 02:30 PM
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Originally Posted by fourthmeal
Never ever EVER clean a Karman Vortex MAF. To clean it = to kill it.

You can go into the box and replace the damaged ribbon of metal with a piece of foil, but often it won't run quite right again.
I disagree. I used CFC MAF cleaner and noticed immediate responsiveness and smoother idle. But to each their own.

Originally Posted by lslover92
i found one on ebay i am going to buy, do i have to do anything reseting on the ecu i have to do , or do i just instal the new one and plug it up ,
AFTER the install, find the EFI fuse in the engine fuse box, pull it, and it will clear the codes/learning modes of the ECU.
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Old Sep 30, 2009 | 04:54 PM
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how long should the efi fuse be out for , before i plug it back in, also should the battery be disconected, while doing this
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Old Sep 30, 2009 | 05:12 PM
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30 seconds to a minute should be sufficient. Pulling the fuse equates to disconnecting the negative terminal on the battery, but pulling the fuse won't cause your radio presets, seat presets, clock, etc, to lose their settings like they would if you disconnect the battery.
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Old Sep 30, 2009 | 07:02 PM
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oh, ok , i appreciate all of the feed back and info once again, the new one should be here in a couple of days, ill let you guys know how everything goes
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Old Sep 30, 2009 | 07:11 PM
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i almost forgot can anyone tell me were the efi fuse is located,
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Old Sep 30, 2009 | 07:33 PM
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Originally Posted by avalon42
AFTER the install, find the EFI fuse in the engine fuse box, pull it, and it will clear the codes/learning modes of the ECU.
Originally Posted by lslover92
i almost forgot can anyone tell me were the efi fuse is located,
Engine bay bud. Pull the cap off, flip it over, follow the diagram, and it will tell you which one the fuse is.
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