Will engine run with MAF and cleaner hose removed?

Discussion in '80-Series Tech' started by e9999, Jul 19, 2005.

  1. e9999

    e9999 You want to do what...? Moderator

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    Thinking about spraying some cleaner in the throttle body the next time I have the air filter off to see if that will clean things up a bit without having to take the throttle body off, just a quickie, taking the air cleaner hose off and exposing the TB opening. Of course, then the MAF would no longer be functional.
    Would the engine run with the air cleaner hose / MAF off - in case I decide to do this also with engine running to suck the cleaner in there as far as it'll go?
    (Or is this a stupid idea? Yes, I'll admit I still think like a carb guy...)

    Yes, I'm also aware that it's better to remove the TB, but this would be a quick attempt at cleaup without any real additional work besides taking the air filter off.

    I may do the SeaFoam PCV bit later too.

    (any new developments on the MAF cleaning PM?)

    TIA
     
  2. parabola

    parabola

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    If you pull off the MAF the car should fall back to fueling off of manifold pressure and run that way. It will run poorly though. I wouldn't drive it that way but it should idle enough to suck down some cleaner.
     
  3. parabola

    parabola

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    Oh, and be sure to actually disconnect the wiring to the MAF instead of just unhooking it's airflow.
     
  4. landtank

    landtank SILVER Star

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  5. e9999

    e9999 You want to do what...? Moderator

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    OK, but no what? no running ? not a good idea?
     
  6. cruiserdan

    cruiserdan SupportingVendor Emeritus Moderator

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    Not a good idea. I don't think I'd try it.
     
  7. e9999

    e9999 You want to do what...? Moderator

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    not try to run or not try to spray?
     
  8. cruiserdan

    cruiserdan SupportingVendor Emeritus Moderator

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    Not running the engine.
     
  9. e9999

    e9999 You want to do what...? Moderator

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    OK, good to know. Dang, it's all opened up ready to go. Why do you think it would be bad to run the engine without the MAF?
     
  10. cruiserdan

    cruiserdan SupportingVendor Emeritus Moderator

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    It will have no idea what it is doing. In addition the heated wire could be damaged because no air is being pulled across it.

    What will be happening is the engine will try to run but the computer will not see any air movement and won't know what to do about fuel.

    Why don't you try it and see what happens. You have my number and I can supply whatever you fry....:grinpimp:
     
  11. parabola

    parabola

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    He should unhook the MAF entirely. The hot wire won't be damaged because it won't be powered.

    Dan, is there a MAP sensor on these trucks?
     
  12. cruiserdan

    cruiserdan SupportingVendor Emeritus Moderator

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    No MAP on the 1FZ.

    unplugging the MAF will throw codes that will need to be cleared, do remember that.
     
  13. parabola

    parabola

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    Ah, well, no MAP, it probably ain't gonna run without the MAF. :doh: for my assumption that it had one. I stand by the hot wire comment though! :flipoff2:
     
  14. Rookie2

    Rookie2

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    After removing and cleaning my TB once a time ago, I forgot to reconnect the wire harness for the MAF. Turned over, but immediately ran very sluggish and proceeded to die. And as Dan said, through a CEL MAF code. After taking a look-see, saw my mistake, reconnected the MAF and it started up and ran fine.

    :beer:
    Rookie2
     
  15. e9999

    e9999 You want to do what...? Moderator

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    OK, I didn't run it without the MAF. Took your advice to heart guys. Just sprayed everything with this NAPA stuff. Worked great. Loosened up all the gunk. Now spotless at least for what I can see. Used Doug's trick. I jacked up the side of the rig so that most of the crud flowed out. Good thinking that Doug!
    Started fine with no smoke.
     
  16. landtank

    landtank SILVER Star

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    NO as in answering the question posed in the title of this thread. If you disconnect the MAF, the engine will not run. It will start and then stumble and die.


    Straight forward question with a straight forward answer.
     
  17. e9999

    e9999 You want to do what...? Moderator

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    Thanks. Well, I didn't try to run it cuz I didn't want to take a chance on a problem and also possibly have some weird codes in there before taking a smog test. However, from what I've read elsewhere and what was mentioned above, I am guessing that it would have probably run if the MAF is disconnected.
     
  18. Rookie2

    Rookie2

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    ?? who said that it would?
     
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