what could it be ......a valve?

Discussion in 'Technical' started by sam03rc, Sep 12, 2010.

  1. sam03rc

    sam03rc Member

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    you mean the low readings on 3 and 7 right? the ones under 100?

    the spark plugs are more white than glazed ill take a pic and post it tomorrow so ya'll can see it for yourself. and i did buy gas at a different place the last 2 times and i havent noticed a big difference in it the last time untill last night.

    ill check over the exhaust too tomorrow to see if i have any leaks because i just thought of it. i mean if there is and its just right it could sound like a tick right?
     
  2. Mavman72

    Mavman72 Gone backwards but lookin' forward

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    Yup 3/7
    Yup exhaust leak can sound like valvetrain noise.
    Good luck!!!
     
  3. sam03rc

    sam03rc Member

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    alright ill check over it tomorrow thanks guys I'm really hoping its not a valve-train issue don't have that kind of cash
     
  4. sam03rc

    sam03rc Member

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    this is a pic of what the plugs look like im going out now to look at the exhaust for any leaks
     

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  5. Mavman72

    Mavman72 Gone backwards but lookin' forward

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    Plugs look a bit lean...Check your ignition components for a bad wire/weak coil.
    Have you put a new gas filter on it lately??? Bad fuel flow/pressure or a lean carb adjustment may be your problem. Gotta check those two low cyls though. Put some oil in those low ones and re-check compression...If it goes up...Bad rings. If it stays the same... Bad valves on those two cyls. Was the engine cold when it acted up? if it was hot...I would lean towards the coil going bad on you. Good luck!!!
    PS: Its just about time for a timing chain on that car if it hasnt been done yet.
     
    Last edited: Sep 13, 2010
  6. sam03rc

    sam03rc Member

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    the engine was hot been driving for about 40 miles before it acted up. i replaced the fuel filter about a month ago and the coil is only 4000 miles old( about 5 months now). i looked for exhaust leaks and im not seeing anything loose. i would understand if it was a fuel issue but now that i know that i have low compression on those two cylinders i shouldnt drive it anymore right? ( its the original number matching block ) and when you say put oil in them what do you mean?
     
  7. Mavman72

    Mavman72 Gone backwards but lookin' forward

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    Put a tablespoon full of oil in the weak cylinders and re-test for compression. The oil will create a temporary seal between the rings and cyl bores. If the numbers now rise, you have bad rings on those two cyls.To find the exhaust leak (if you have one) the engine needs to be running. Then you listen around the exhaust manifolds where they meet the heads with a length of rubber hose held to your ear like a stethoscope and the other end on the area you want to listen to.Do this at all joints and mating surfaces in the exhaust sys. If you have a leak you will find it this way.
    Is the car running fine now or is it still low on power and hiccuping. Its possible the T chain has jumped if the engine is still exhibiting low power.
     
  8. sam03rc

    sam03rc Member

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    i havent taken her out towed her home and pushed her into the garage and she is parked only idled her to get the temp up to do a compression test and idled fine and did the other night too but didnt when i put the pedal down. didnt want anymore damage to be done if something let go
     
  9. 302-72-mav

    302-72-mav Member

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    i used to buy gass at the small corner gas/convenience store

    and once i even bought there premium gas before i went to the track and i didn't notice and difference

    but then a buddy of mine bought me gas for a ride home in the mav from a ( shell ) gas station and he put premium / Vpower and wow i noticed a difference in power and i think gas mileage to so now i only get it from shell or (am-pm) in premium
     
  10. sam03rc

    sam03rc Member

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    gas with carbs is touchy i know that had that issue couple months ago and now i only get from ( wawa and 7-11 )
     
  11. dkstuck

    dkstuck Member

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    WA-WA got great hoagie buns too!!!
     
  12. sam03rc

    sam03rc Member

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    Wawas has some amazing and cheap food in there its awesome
     
  13. mashori

    mashori Member

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    is the carb ok after that pop? any chance you bent the throttle blades?
     
  14. sam03rc

    sam03rc Member

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    alright call me stupid but i did the first compression test wrong so throw that out ( the first time a only cranked it over two times and then wrote down the compression ) found out that i need to crank it over about 5 times or till the gauge stops helps if i read the directions that came with the compression tester gauge.



    these are the numbers i got once i did it right
    1- 150
    2- 150
    3- 140
    4- 135
    5- 160
    6- 150
    7- 140
    8- 140


    these numbers sound much better dont they?
     
  15. Mavman72

    Mavman72 Gone backwards but lookin' forward

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    Yes!...Much better, now your back to fuel/ignition as long as all the valve train checks out. Good luck!!!
     

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