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  • zaken1 09/03/11 1:03 am PST

    Your description is a perfect example of what an engine sounds like when the timing chain has broken or jumped out of position. This often will not set a trouble code. Time for a new timing set; which on the 4.7 SOHC engine contains 3 different timing chains, 2 guides, 3 tensioners, and 2 timing arms. The deluxe timing set for the sport engine also contains 2 cam sprockets; a crank sprocket, and an idler sprocket.


    I don't have enough information to be able to make an intelligent comment about the marks on the secondary chains. But if you ran a cylinder compression test, and found that the compression is less than 110 psi; this would prove that there is a problem in the timing drive. It might be a sheared woodruff key, or maybe there is something about the marks on the chains which is critical.

    A problem in the crank or cam position sensors would not make the motor crank as if there was no compression; and if there was low or no compression in a compression test; it could not possibly have anything to do with sensor problems.

    Source: 

  • Stever@Edmunds 09/03/11 8:33 pm PST

    You can reply in this thread by clicking the Answer this Question button and that will help keep all the information in one spot. Thanks!

  • zaken1 09/03/11 9:04 pm PST

    If you tried to open a new question to post a response; it will not be able to be seen here. Please click the "answer this question" button under THIS response, and post the information here. Then click the "submit answer" button.

  • turboford928 09/08/11 5:13 pm PST

    new timing chain on and in time! but still same thing could i have an oil pressure problem ie: bad oil pump, bad sending unit, excessive sludge on pump pick up as dodge 4.7 is known for that even with regular oil changes.

  • turboford928 09/08/11 5:38 pm PST

    oh and by the way this is why i dont like newer cars with overhead cam engines!!! just give me an old school V-8 any day!! thanks for the help!

  • zaken1 09/08/11 10:51 pm PST

    If you just ran a compression test, and posted the pressures you got; we would know a lot more about what is going on here. Why muddle around in speculation and theories; when tests can be done so easily?

  • zaken1 09/12/11 4:42 am PST

    There is one other thing that can make the motor have no compression; and that would be if a camshaft broke. I would strongly recommend pulling the valve covers and cranking the motor; while watching to see if the valves are being opened and closed in all the cylinders. I would also independently confirm by inserting a rod in the spark plug opening of # 1 cylinder that the piston in # 1 cylinder is actually at TDC when the timing marks on the crank pulley say it is. Sometimes the damper in a crank pulley comes loose and the marks move to a different position.

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