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  1. #1

    Default This is just getting old

    well i just got the truck back from the mechanics today and it is still running like junk. she is a 92 k1500 with the 5.7. i took it in because i couldn't work on it anymore due to shoulder surgery. they said it was just the vaccume line going into the map sensor and that solved the idling issue and stalling out. so on the way back she would backfire like none other wile accelerating I've had this problem before but i fixed it with the distributer cap and rotor and it has never been this bad. and it was smelling like oil so i got her home and oil was actually coming out of the dipstick and burning on the manifold. (they probably just didn't put the dipstick all the way back in). so here is what i have done to it so far since i got it. fuel filter, air filter, distributer cap and rotor, spark plugs, and finally the O2 sensor.

    any input would be much appreciated, i am completely stumped.
    [SIGPIC]

    '92 k1500

  2. #2

    Default

    Could possibly be an egr valve issue. Did they pull some spark plug wires off? They may have not put the wires back to the right plugs. Are you wires good? you could always spray them with a water bottle in a dark garage and watch for arcing. if you run it after you pushed the stick back in, does it push the dipstick back out and shoot oil all over again?

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  3. #3

    Default

    Your egr could be at fault or your intake manifold could be getting clogged up with carbon. My mechanic buddy told me the egr ports in the intake manifold on his truck was so clogged up he had to chisel them out to clear them.

  4. #4
    Jr. Apprentice revscott's Avatar
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    Default

    Quote Originally Posted by dogred View Post
    Your egr could be at fault or your intake manifold could be getting clogged up with carbon. My mechanic buddy told me the egr ports in the intake manifold on his truck was so clogged up he had to chisel them out to clear them.
    Man!! I wonder if that is what's wrong with mine? New egr, new solenoid, new hoses and still it isnt working correctly!
    The Rev

  5. #5

    Default

    Quote Originally Posted by dogred View Post
    Your egr could be at fault or your intake manifold could be getting clogged up with carbon. My mechanic buddy told me the egr ports in the intake manifold on his truck was so clogged up he had to chisel them out to clear them.
    I'm gonna second this one. My buddy and I just had to do the same thing, but it was the EGR hard pipe on the truck that we had to clear out.

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  6. #6

    Default

    well i will take a look today with the spray bottle to see if it is the plug wires. but it sounds like i might be taking it back to the mechanics. having one arm in the sling makes it difficult to work on my baby...

    thanks for all the imput!

  7. #7

    Default

    Hello, Iowan:

    Wow, I am so sorry for your troubles.

    There are some other sensors or devices that control or change the idle on that motor I would have checked by someone who can test everything (not that place you used, please).

    I would also have a shop test the O2 sensor that is mounted into the exhaust near the catalytic converter. If your converter is clogged, you can get some funkiness with the 02 sensor, and the converter if clogged can cause trouble with the motor running rough, etc. If you have the original Cat Converter on there, it may be time to replace it. I have a '94 truck and I have had to replace mine twice. For me it was probably due to too much moisture because I don't drive it enough.
    1994 Chevy K2500 Silverado, 454 (modified), original owner.
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  8. #8

    Default

    I've put a couple of o2 sensors in it because I've heard aftermarket ones can be junk out of the box. i should take the truck to a shop that has a scope that can make sure everything is working fine

  9. #9
    Sr. Apprentice
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    Default

    It could be the IAC -- it won't throw a code all the time when they fail. The IAC controls the idle when warm, and will also wreak havoc with overall performance and fuel economy if it's not working. They don't generally "fail" completely, they get dirty and are unable to function correctly.

    Pull the NEG battery terminal. On the throttle body behind the TPS sensor the sensor with the SQUARE electrical connector is the IAC sensor. Remove the sensor, spray the spring with carb cleaner and give it a gentle scrub. Spray and scrub inside the IAC port on the throttle body. If you can remove the throttle body, you'll be able to clean it better -- but it isn't always needed. Reconnect sensor.

    Reconnect the NEG terminal. Jumper pins A+B on the OBDI port under the dash (paperclip or wire). Turn the key to the "ON" position but do not start the vehicle. Let it sit in the "ON" position for 60-120 seconds. This forces the IAC to return to the CLOSED position. Turn key OFF. Remove jumper pin from A+B pins on OBDI. Start vehicle.


    You can also try skipping the whole cleaning process... and just clear the ECM and reset the IAC position. See if that helps. Should take no more than 5 minutes.
    My lug nuts require more torque than your Honda makes.

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