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????

JimsGX

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

JimsGX

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.

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

avalon42

iTrader: (1)

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.

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.

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 ,

avalon42

iTrader: (1)

I disagree. I used CFC MAF cleaner and noticed immediate responsiveness and smoother idle. But to each their own.

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.

lslover92

how long should the efi fuse be out for , before i plug it back in, also should the battery be disconected, while doing this

JimsGX

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.

lslover92

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

lslover92

i almost forgot can anyone tell me were the efi fuse is located,

avalon42

iTrader: (1)

Engine bay bud. Pull the cap off, flip it over, follow the diagram, and it will tell you which one the fuse is.