Better MPGs following MAF cleaning...How often do you clean yours?

[bigwapitijohnny]

I have completed the following mods (Deckplate, Trueflow filter, ISR mod, Seafoam, and MAF cleaning) and have been tracking my mpg. I have been averaging roughly 17 mpgs (zero out my trip odometer, divide miles/gallons of gas). I did not notice any cumulative effects from all of the mods UNTIL, I cleaned my MAF sensor. It was dirty, and the electronic 'connector' was somewhat loose due to a bug of some sort. Anyway, I have noticed an increase in gas mileage to 18.6 mpgs since the cleaning :thumbup:. This mileage includes same amount of city driving, using ac, and towing a trailer with a riding lawn mower :D. How often do all of you clean your MAF sensors?

[Seanz0rz]

i have yet to clean mine, that will be this weekend's endevor, or sooner if i can track down some brake cleaner.

[Elton]

i think i cleaned mine along time ago

[MTL_4runner]

I try and clean mine every oil change. I also clean the TB at the same time too.

[bigwapitijohnny]

Will cleaning the throttle body help as well?  What does the throttle body do?  Sorry about my ingorance... :headscratch:

[humanoid]

I think cleaning the TB will help with the throttle response if anything and maybe make your truck feel livelier. As for cleaning your MAF, 4x4wire.com has a great write-up:

http://www.4x4wire.com/toyota/maintenance/tacoma_4runner_30k/maintenancep5.html

You'll need to scroll down to about the middle of the page.

[MTL_4runner]

Will cleaning the throttle body help as well? What does the throttle body do? Sorry about my ingorance... :headscratch:


Cleaning the throttle body is really more for idle quality and can help keep your IAC (Idle Air Control valve) from getting the severe carbon buildup that causes very rough idle. There may be some slightly better throttle response (esp at very low throttle plate angles) hence it might feel a bit peppier from a dead start. I do it quite often but it's definately something to do if you have not done it in a while.

HINT: When your done cleaning, try and get the truck started ASAP and certainly before the cleaner dries (helps get the carbon out of the TB area). Start the truck initially with your foot completely to the floor and let up once the engine has caught.

[mkgarrison5]

i tried spraying throttle body cleaner (carb\injector) into the inake while the truck was running and when i took off the main air tube and the truck kept shutting off.. i am assuming bc of the maf sensor? i unhooked the tube at the TB. what can i do to keep the truck running while spraying cleaner down the TB?

[MTL_4runner]

i tried spraying throttle body cleaner (carb\injector) into the inake while the truck was running and when i took off the main air tube and the truck kept shutting off.. i am assuming bc of the maf sensor? i unhooked the tube at the TB. what can i do to keep the truck running while spraying cleaner down the TB?


Yep, you can't unplug the intake while the vehicle is running or it will shut off almost immediately (you can unplug the intake anywhere except in front of the MAF...ie essentially just the airbox) nor do you need to. The TB cleaning needs to be done with the vehicle OFF, then reconnect the intake tube and fire up the motor to clear it all out. I use an old toothbrush and it helps to have someone in the truck floor the gas pedal (again, engine OFF) so you can use the toothbrush on the TB bore to really scrub it clean. Keep the toothbrush soaked with carb cleaner and the carbon will just dissolve leaving behind a nice shiny throttle body bore. Don't forget to clean the throttle plate as well.

[mkgarrison5]

yeah i left the truck off and unhooked the main air tube and used a cloth and TB cleaner and did what i could with that and sprayed a generous amount in the TB itself, cranked the truck up and let it suck the rest through the motor.. ill use a toothbrush next time.. how much TB clean can you spray in there without messing something up??

[MTL_4runner]

yeah i left the truck off and unhooked the main air tube and used a cloth and TB cleaner and did what i could with that and sprayed a generous amount in the TB itself, cranked the truck up and let it suck the rest through the motor.. ill use a toothbrush next time.. how much TB clean can you spray in there without messing something up??


You probably don't need to unload an entire can in there, but you could do 1/2 can no problem and a toothbrush works a heck of alot better than a rag.....try it next time and you'll see what I mean. After using the toothbrush, blast the TB with cleaner one last time to wash any of the residual carbon into the intake. Just remember to hold your foot completely to the floor when starting the motor, then let off after it catches and starts to rev high. Keep the RPMs about 2500-3000 for about 1 minute to burn off any remaining cleaner.

[mkgarrison5]

ok sounds good.... is it possible to spray into the pcv valve while the engine is running to allow the motor to suck up the cleaner?? just curious.. thanks mtl


-side note on the 05 corolla, i pulled the pcv valve hose off the pcv valve to suck up some seafoam and the motor kept shutting off. i am assuming to unscrew the pcv valve itself and seafoam it that way?? thanks!

mike

[MTL_4runner]

ok sounds good.... is it possible to spray into the pcv valve while the engine is running to allow the motor to suck up the cleaner?? just curious.. thanks mtl

Yes, you can do that if you want to.....keep the RPMs up or the motor will stall.



-side note on the 05 corolla, i pulled the pcv valve hose off the pcv valve to suck up some seafoam and the motor kept shutting off. i am assuming to unscrew the pcv valve itself and seafoam it that way?? thanks!

Same as above, the PCV line creates a HUGE vacuum leak so keep the RPMs up or find a smaller vacuum line to use.

[mkgarrison5]

when i pull my taco's pcv out it doesnt stall.... when i pull the hose out of the pcv valve itself on the corolla it stalls imediately even before i can get seafoam in it

[surf4runner]

i just changed my plugs, and will do the MAF next week to see which helps my MPG the most.
ill post up what i see.

[4x4Fink]

Weird thing...I cleaned my MAF and drove it about a tank or so and noticed worse gas mileage. I only got about 220 miles on my tank versus my usual 240. However, I did notice a performance gain...maybe it's just my imagination but it seems to be better on the throttle side of things.

Fink

P.S. - Quick question for ya Jamie, I noticed that there are two kinds of CRC Brakleen...Chlorinated (red can) and Non-Chlorinated (green can). I used the red/Chlorinated one...is that a problem?

[mkgarrison5]

i used the red can with no problem.. it helped my gas mileage along with new plugs, new fuel filter and seafoam.. went up 2-3 mpg.. did you reset your computer? anytime you clean sensors or replace them you should disconnect the negative terminal of your battery for a few minutes for it to reset and give it time to readjust.. imo

[MTL_4runner]

Quick question for ya Jamie, I noticed that there are two kinds of CRC Brakleen...Chlorinated (red can) and Non-Chlorinated (green can). I used the red/Chlorinated one...is that a problem?


The chlorinated solvents use chemicals like Methylene Chloride aka Dichloromethane (MeCl, often used as a paint stripper), Perchloroethylene aka Tetrachloroethylene (Perc, often used as dry cleaning fluid) and Trichloroethylene (TCE) which are considered environmental hazards to groundwater and are suspected carcinogens.

Non-chlorinated solvents use Toluene, Xylene and Acetone which while very hazardous (and VERY flammable) are apparently exempt form VOC regulations (for now).

So to answer your question, no it doesn't matter since you're only giving it a small exposure time (enough to clean the wires then air dry). Fink, did you by chance pull the negative battery terminal after you cleaned the MAF? If you did not, you should or it will take some time for the ECU to adjust (hence the worse gas mileage and better throttle response). Even when you do it, it takes a few miles for the ECU to relearn.

[4x4Fink]

Jamie, I had the negative battery terminal disconnected the entire time I was cleaning the MAF. It looks like my mileage may be returning to normal now, I may have just driven with my foot in it a little bit more this last tank.

If it doesn't get any better this tank I'll pull the terminal again and see if that helps.

Thanks for answering my question about the two different cans, a wealth of knowledge to say the least.

Fink

[MTL_4runner]

I think the ECU is just in relearn mode which will tend to richen the mixture until it gets dialed in.
This will give you slightly worse gas mileage but a little more "seat of the pants" fun.

[4x4Fink]

Sweet, thanks Jamie. It looks like my mileage might be leveling back out.

Thanks again,

Finkhttp://i38.photobucket.com/albums/e102/4x4Fink/4Runner/devil.gif