Forum Discussion

C_Schomer's avatar
C_Schomer
Explorer
Jul 14, 2014

How to clean a mas sensor?

I just got back from Co with an 04 Jeep GC 4L auto - 35re I think. It ran terrible in Co and it up shifted way too quickly and wouldn't kick down at all to direct with the cruise on. I seldom felt the converter shifts. It acts much better here but it really needs to stay in the gears a little longer. It had a k&n which I immediately put where it belongs and replaced with paper, in Denver before I hit the road. I wonder if it has anything to do with an oily sensor. I want to check it in the morning. What Is safe to clean them with? IPA maybe? That's what I clean my micron gauge sensors with. TIA! Craig
  • MEXICOWANDERER's avatar
    MEXICOWANDERER
    Explorer
    Jul 14, 2014
    Also CRITICAL (a few steps greater in importance than ESSENTIAL)

    Buy a bottle of DEOXIT D100

    Disconnect each and every sensor wire junction and add one or two drop of DeOxit D100 to the contacts even if they are gold flashed. There is nothing else on the face of the earth that works like this stuff. For low millivolt connections DeOxit D100 is a miracle. Even for antennas, USB connections, what have you.
  • C_Schomer's avatar
    C_Schomer
    Explorer
    Jul 14, 2014
    I couldn't remember exactly what they were called. Thanks everybody! I'll get the right cleaner today. I know the cleaner for the throttle body is special so it won't take off the lube coating or whatever it is.
    I wanted something for the desert and to check out the off road scenery in the mtns and I read up on Jeeps for a long time before buying one. I got the GC cuz I also wanted the comfort and cargo capacity. I bought a black 99 last year and it's way too hot around here so this 04 is white. I thought the WJ was appropriate... Wuss Jeep! Craig
  • nomad297's avatar
    nomad297
    Explorer
    Jul 14, 2014
    marcsbigfoot20b27 wrote:
    If you are talking about the MAF (mass air flow) sensor....they make a maf spray that leaves no residue.
    You can get it at the auto part stores.


    Technically, MAS is correct. "Air-flow" is a hyphenated word, so only the "A" should be used as its acronym. However, adding "sensor" afterwards is redundant. It is commonly referred to as a "MAF" and a "MAS". Both are the same thing.

    Bruce
  • KJINTF's avatar
    KJINTF
    Explorer
    Jul 14, 2014
    Your jeep has a Speed Density EFI system thus NO MAF sensor
    You have a MAP sensor inside the intake manifold past the butterfly throttle
    Clean the throttle body

    Your Jeep is a WJ series
    Check out Jeep forums for loads of great info

    Remember
    Speed Density EFI = MAP as in Manifold Absolute Pressure sensor inside the manifold - All WJ and TJ series used this system

    Mass Air Flow EFI = MAF sensor located before the throttle - wires that heat up

    Love my Jeeps and my DRBIII
  • westend's avatar
    westend
    Explorer
    Jul 14, 2014
    Yup, Isopropyl alcohol or ether is what I use. Neither of them will leave a residue.
  • marcsbigfoot20b's avatar
    marcsbigfoot20b
    Explorer
    Jul 14, 2014
    If you are talking about the MAF (mass air flow) sensor....they make a maf spray that leaves no residue.
    You can get it at the auto part stores.

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