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  • GameboyRMH

    July 2, 2009 8:37 p.m. GameboyRMH SuperDork

    My Samurai has a serious case of the gremlins...

    Today it went from running properly for once to a suddenly low and rough idle - dropped from a smooth 1krpm to as low as 250rpm or in one case zero. It still starts easily as long as I keep my foot on the gas and although it runs rough, it's definitely still firing on all 4 cylinders.

    The engine has brand new:

    • Timing belt
    • Head gasket
    • Distributor
    • Plug wires

    Has had not too long ago:

    • Carb & intake cleaning
    • Oil change
    • Coolant change and pressure test
    • Valve adjustment

    Engine was totally rebuilt less than 2 years ago, but obviously he missed the timing belt, probably screwed something up with the head gasket, and definitely left it in reach of voodoo-practicing enemies.

    Any ideas? I don't know when last the fuel filter was changed but that's not something you'd expect to cause a problem so suddenly.

  • 2002acr

    July 2, 2009 8:41 p.m. 2002acr New Reader

    Seems like a vacuum leak. EGR valve? or idle air control valve.

  • GameboyRMH

    July 2, 2009 8:51 p.m. GameboyRMH SuperDork

    I checked all 4 vacuum lines, they seem intact and well-secured. No EGR or IAC valves - but there's one unknown doodad on the carb, I'll have to look it up in the repair manual.

  • 2002acr

    July 2, 2009 9:03 p.m. 2002acr New Reader

    I brain farted on the carb, that would not have an IAC. I would check the unknown doodad, if it is an emission control device it would be a suspect.

  • Jensenman

    July 3, 2009 7:00 a.m. Jensenman MegaDork

    I vote for something stuck in the low speed jet in the carb. It doesn't take much, something as small as a salt grain can do it. BTDT.

  • GameboyRMH

    July 3, 2009 7:21 a.m. GameboyRMH SuperDork

    Jensenman wrote:

    I vote for something stuck in the low speed jet in the carb. It doesn't take much, something as small as a salt grain can do it. BTDT.

    This may be it. One suggestion I ran across while searching last night was to try running it hard since it may be something stuck in the carb and the extra fuel flow might clear it out. So this morning I ran it high and hard and it actually started idling higher than usual, but a few minutes later it went back to the precariously low idling.

  • GameboyRMH

    July 4, 2009 9:03 a.m. GameboyRMH SuperDork

    Well it looks like it passed whatever "carb stone" it had, just to be safe I changed the fuel filter (and of course had to replace a rotten fuel line).

 

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