P0300 after replacing intake manifold Gaskets

Tiny
BCMULLEN95
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  • 1999 BUICK CENTURY
  • 102,000 MILES
I replaced the intake manifold gaskets, 4 exhaust push rods, two rocker arms and now I have multiple misfire and the car runs like crap. I broke the rocker arms and push rods by switching the intake and exhaust push rods unintentionally. Is there a possibility that I could have done other damage that I can not see from just a general inspection. Could I have bent the cam shaft or the valves by putting the push rods in the wrong spot?
Wednesday, March 14th, 2012 AT 12:56 AM

7 Replies

Tiny
CADIEMAN
  • MECHANIC
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Are they all the same size?
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Wednesday, March 14th, 2012 AT 1:16 AM
Tiny
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Cam shafts dont bend they break. It is very poss. If you have done all this damage you have bent a valve. Start with a compression test. Then come back with reading. You may have to have the head rebuilt and damaged parts replaced.
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Wednesday, March 14th, 2012 AT 1:31 AM
Tiny
BCMULLEN95
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I am going to check that but I don't that I broke the came, I could see it rotate all the valves when I manually rotated the engine. I am also going to check timing. I was just curious as to what are the possibilities of what could be causing the p0300 code after I did what I did.
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Wednesday, March 14th, 2012 AT 4:50 AM
Tiny
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Youll need to do a compression test first!
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Wednesday, March 14th, 2012 AT 11:05 PM
Tiny
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Compression test is as follows cylinder #1 175 psi, #2 0, #3 0, #4 120 psi, #5 0, #6 155 psi. So as I am to assume that I bent the intake valves on those three cylinders and need to check to make sure the other valves are not bent.
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Thursday, March 15th, 2012 AT 2:28 AM
Tiny
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Youll need to remove the valve covers and check the valve operation on those 0 cylinders. Watch the valves on those 3 cyls. To be moving in and out. Somthing broke those rockers. If any valves arent moving. You will need to pull the heads and have them checked. It maybe cheaper to buy used heads or a reblilt pair
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Thursday, March 15th, 2012 AT 8:46 PM
Tiny
BCMULLEN95
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I bent the valve, replaced the heads and the car runs better nor than before I damaged it.
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Monday, May 12th, 2014 AT 1:07 PM

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