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Engine problem

Discussion in 'Planes, Trains & Automobiles' started by Grizmoblust, Jan 31, 2011.

  1. My engine is running weird a lot lately. It was making thunking noises. I took a look at the head gasket, apparently the oil was inside of the tubes, touching the spark plugs. I replaced head gasket and spark plug. The thunking is no longer there.

    However another problem arise, the rpm is going up and down when I drive more than 5 minutes. But the rpm never exceeded 1.5k nor below .7k. It sounded like the gas is low but it is full. I asked my genius friend's dad, he doesn't know as well. So I'm here, asking you blades, do you guys know this problem?

    And no, I rather fix it myself than taking to the car shop since I have hard time trusting people/business nowadays.

    Best regards!
     
  2. Year, make, and model?
     
  3. You have oil on in your spark plugs? Sounds like a broken piston ring is leaking oil into the head
     
  4. It Depends On The Year, But Sometimes Idle Control Valves Are Run By Vacuum So You Need To Check All The Lines. Also Check The Mass Air Flow Sensor.

    Also Cound Be A Bad Fuel Injector Not Delivering Enough Fuel, So The IAC Tries To Correct The Idle Contantly.
     
  5. Thats already replaced.


    Furthering into detail of the problem of my car.

    The rpm only acts crazy once I take off and drive around for 5+ minutes. Once I fully stop, it starts going up and down, from 1.0 to 1.5 rpm. If I press the gas to above 1.7 rpm, it never acts.

    However, If I just start the car, and left it idle, not moving or anything like that, it has no problem whatsoever until the gas is out. Seriously.

    My car is 95 Honda with a stick.
     
  6. Civic? If It Is, Thats Common. Get A New Idle Control Valve.
     
  7. It's a accord.
     
  8. The idle fluctuation is caused by a vacuum leak.

    Do all the usual vacuum leak trouble shooting stuff and you should be good. By the way, oil on the plugs doesn't always mean the headgasket or rings are worn. I've had the valve stem seals leak on Hondas that I've owned which caused oil to get into the cylinders. A leak down test is the only way you can find out for sure, I would have done that before you pulled the head.
     
  9. Another thing you can change that can cause engine issues is your PCV valve. It sits on top of the valve cover and controls vacuum. I bought a 91 Prelude that had "engine issues" and for about $3 at Advanced the "problem" was fixed! If you just want to check it this is what you do. Find the PCV valve by looking for a plastic tube (usually a right angle) with a small black rubber hose going to it on top of the valve cover. Put it out and shake it. If it rattles easily, then it is ok. If it doesn't make a noise, then it is gunked up and should be replaced. Not all stores seem to carry them so either call ahead if it is a drive, go to dealer, or order online. I can tell you know what you are doing with the gasket replacement, but it seems this is often overlooked by people as I have pointed it out several times to friends who knew their way around a car.

    Good luck!
     
  10. its definitely an idle control issue, id lean more towards hardware than a vacuum leak, but thats me. it could also be gunk buildup where the idle air control solenoid seats.

    definitely check your vacuum lines first before spending more money. do you have a check engine light on?
     
  11. Wow thanks a lot guys. I'll check my engine out this weekend when I can.
     

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