Anybody ever try this and with what results?

slow91fj90 · 09-24-08, 12:56 PM

Saw this on Downeys site and was curious.

MASS AIR SENSOR MODIFICATION*
* Tampering not legal,
should only be modified for racing use.

The following adjustment can be used to richen or lean the air/fuel mixture from the factory setting. This adjustment could be necessary when using a Big Bore Throttle Body or other EFI modifications. The mass air sensor (MAS) is found on top the air cleaner canister on 1985-95 Toyota vehicles. The sensor is an aluminum housing with black plastic lid. Cut the seal holding the black plastic lid in place. Gently pry the lid from the housing. To adjust, first mark the original location of the hold-down clamp on the gear wheel so you can return to stock setting if necessary. Loosen the clamp screw and rotate the gear wheel a few teeth as necessary. Clockwise leans the mixture, counter-clockwise richens the mixture. After adjustment, replace the top plastic lid (see Warnings below).
WARNING #1 - Use caution when cutting the top lid seal with a hobby knife so that plastic lid is not cut or damaged.
WARNING #2 - DO NOT let spring loaded gear wheel unwind, you will not be able to find stock setting/home base.
WARNING #3 - Ensure you establish a good seal when replacing top lid, moisture can destroy the sensor electronics.
WARNING #4 - DO NOT use an adhesive which creates a gas or fumes when drying, fumes will coat and destroy the sensor electronics – you’ve been warned!

nicholas · 09-24-08, 01:22 PM

I never never heard of this. I wonder if this would help solve some of the fuel management issues the 93-94's have with the S/C's

bhmmapping · 09-24-08, 01:37 PM

if you are going to open that up be very, very careful. People have accidentally cut wires, lost their mark and not been able to definitively return to factory settings... search on AFM should bring back some horror stories.

NLXTACY · 09-24-08, 01:42 PM

I did this on my 4Runner when I had my fuel injectors blueprinted and I had my throttle body ported. It made a very noticeable difference. The newer LCs (95-97 I think) dont have this.

slow91fj90 · 09-24-08, 04:44 PM

NLXTACY, what did you do, lean it out or richen it up?

09-24-08, 04:44 PM	#5
slow91fj90 IH8MUD Regular Join Date: Jun 2006 Location: Fairfax, VA Posts: 287	NLXTACY, what did you do, lean it out or richen it up? __________________ 91 FJ80, 3" OME, 33 PROCOMP MUD TERRAINS, ARB, GARMIN-V, 4:56'S, T-MAXX 10,OOO,NOT LOCKED,MOBILE AIR-CARD.

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09-24-08, 12:56 PM	#1
slow91fj90 IH8MUD Regular Join Date: Jun 2006 Location: Fairfax, VA Posts: 287	Anybody ever try this and with what results? Saw this on Downeys site and was curious. MASS AIR SENSOR MODIFICATION* * Tampering not legal, should only be modified for racing use. The following adjustment can be used to richen or lean the air/fuel mixture from the factory setting. This adjustment could be necessary when using a Big Bore Throttle Body or other EFI modifications. The mass air sensor (MAS) is found on top the air cleaner canister on 1985-95 Toyota vehicles. The sensor is an aluminum housing with black plastic lid. Cut the seal holding the black plastic lid in place. Gently pry the lid from the housing. To adjust, first mark the original location of the hold-down clamp on the gear wheel so you can return to stock setting if necessary. Loosen the clamp screw and rotate the gear wheel a few teeth as necessary. Clockwise leans the mixture, counter-clockwise richens the mixture. After adjustment, replace the top plastic lid (see Warnings below). WARNING #1 - Use caution when cutting the top lid seal with a hobby knife so that plastic lid is not cut or damaged. WARNING #2 - DO NOT let spring loaded gear wheel unwind, you will not be able to find stock setting/home base. WARNING #3 - Ensure you establish a good seal when replacing top lid, moisture can destroy the sensor electronics. WARNING #4 - DO NOT use an adhesive which creates a gas or fumes when drying, fumes will coat and destroy the sensor electronics – you’ve been warned! __________________ 91 FJ80, 3" OME, 33 PROCOMP MUD TERRAINS, ARB, GARMIN-V, 4:56'S, T-MAXX 10,OOO,NOT LOCKED,MOBILE AIR-CARD.

09-24-08, 01:22 PM	#2
nicholas IH8MUD Addict Join Date: Jun 2006 Location: IA Posts: 895	I never never heard of this. I wonder if this would help solve some of the fuel management issues the 93-94's have with the S/C's __________________ 97LX450, 141K, 285CooperSST's, OME851/860's, S/C, CDL 7-Pin, Landtank MAF, Slee SS lines, 100 pads, silicone PHH, Raventai temp, CDan parts throughout($5K+). Chillin' in Cornfeilds (IA) studying.

09-24-08, 01:37 PM	#3
bhmmapping IH8MUD Regular Join Date: Nov 2005 Location: Birmingham, AL TLCA# 18734 Posts: 394	if you are going to open that up be very, very careful. People have accidentally cut wires, lost their mark and not been able to definitively return to factory settings... search on AFM should bring back some horror stories. __________________ Alabama Chapter coming soon: http://forum.ih8mud.com/al-dixieland-cruisers/ Matt 1992 FJ80 - OME 850/860, Bilsteins, ARB...