MY SERVICE ENGINE LIGHT HAS BEEN COMING ON WHEN EVER I GO UP A HILL OR THE MOTOR IS ON A PULL. I HAVE HAD IT CODED AND IT SAYS 4th CYLINDER MISS FIRE. I TOOK IT TO A CHEVY DEALER AND THEY SAY IT IS THE 3 AND 4 VALUE GUIDES ARE TO TIGHT AND ARE MAKING THE VALUES STAY CLOSED. HAS ANYBODY EVER HEARD OF THIS???????
THANKS DSHULL
I've had the same code thrown for the same cylinder on our '99 Suburban w/ a
5.7L MANY times over the years. It generally would happen when under strain at highway speeds going up long hills or even up entrance ramps. I changed the plugs, wires, cap, rotor and even that injector when the intake gaskets finally died. Nothing fixed it until I noticed something. Since it is my wife's daily driver, it does not get much hard running. As long as I get on it a couple times per month and "blow it out" guess what, NO MORE CODES!!! Best I can figure is it was building up some carbon on that cylinder somewhere and causing just enough grief under strain to throw a code. Keep it clear and no issues. I can't recall the last time it threw the code! Who knows, it just may work for you as well.
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