knocking

PONTIAC GRAND AM
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NAVYBUDD
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97 grand am 3.1 120k miles,
I just installed a new intake manifold gasket an i think the job was way over my head. When i finally got the engine back together and fired it up i have a very loud knocking noise.it gets faster as i accelerate. I have moved the car a total of one block cause i am to scared to go further. The sound is very similar to a once quiet ticking i had before. Is this the lifters and if so what are lifters and the location. I also now have a check engine light on.Please tell me i havnt gone to far to save my car,us military guys cant afford new ones. Thanks
Jul 30, 2007 at 10:12 PM
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CLY
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My first guess would be that maybe you got the push-rods mixed up. You had to remove the rock arms and push rods to get the gaskets for the manfold out. The push rods are different lengths. all 6 of the intake push rods are 5 3/4 inches long and all 6 of the exhaust push rods are 6 inches long.

You may have to take it back apart in order to inspect....

Cly
Jul 31, 2007 at 4:59 AM
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NAVYBUDD
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i used a box and cut holes in it to make sure the rods went back where they came from. I did however torque the rockers to 120 inch pounds and i just found in my haynes manual that it is supposed to be 90. Could this be the cause?
Jul 31, 2007 at 7:07 PM
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CLY
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The GM manual says 80 inch lbs. It have pulled the threads out or something. I would take those valvecovers off and have a look. did you change the oil after the repair? I have had some of those that made some noise for 10 to 15 min. The lifters seem to bleed down when not loaded and the longer it is apart the longer they rattle when you start it up...

Cly
Aug 1, 2007 at 4:44 AM