i changed intake gaskets on 97 3800 and now it will start and back fire and die?

1997 BUICK LESABRE
99,000 MILES
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MAXAC
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ive checked plug wires, air leaks and all my sensor plugs.
i can force it to run a few seconds by throttling.
all i get is jerking, spitting and a backfire at the end.
fuel pressure is 37psi. DTCs 0171, 0300
i made a donation for this question as "maxair" moments ago
Oct 3, 2012 at 1:50 AM
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SATURNTECH9
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Did you get all the push rods placed in the right place when you put it all together?
Oct 3, 2012 at 2:19 AM
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MAXAC
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yes i was able to see the lifter tops
how did you know i remove them ?
Oct 3, 2012 at 2:53 AM
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MAXAC
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do you think my lifters are over pumped?
Oct 3, 2012 at 2:54 AM
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SATURNTECH9
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When do the gasket you would remove the push rods.The lifters could be over pumped i helped some one else a while back with a similar problem.That turned out to be over pumped lifters.
Oct 3, 2012 at 3:42 AM
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MAXAC
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i ve definatley seen water in oil over pump lifters.
ill find out in morning
Oct 3, 2012 at 3:47 AM
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SATURNTECH9
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When the lifters are taken out and put back in they can over pump just from.that.
Oct 3, 2012 at 3:57 AM
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MAXAC
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i checked all twelve and can twist at least one per cyl with my fingers easily.
Oct 3, 2012 at 4:24 PM
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SATURNTECH9
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Have you performed a compression test yet?
Oct 3, 2012 at 11:07 PM
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MAXAC
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i did compression check . they all fall between 165 and 185
the last one i checked was 185 and it was one of the ones doing
the backfiring,#5. i didnt remove any rockers or pushrods on
the front head 1,3,5
Oct 4, 2012 at 12:02 AM
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SATURNTECH9
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How did it run before you replaced the gasket?
Oct 4, 2012 at 2:31 AM
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MAXAC
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it ran fine ,but #6 started taking water and finally hydralic locking. there is something that i should mention, after i was done. the cars security wouldnt let me start it. as in no starter funtion at all. i disconected the batt 20 min still nothing, the next morning it was back to normal starter funtion but runing bad.
Oct 4, 2012 at 3:04 AM
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MAXAC
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i appreciate your help and if you think of thing else I'm ready to try
Oct 5, 2012 at 2:59 AM
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MAXAC
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i put #1 piston at tdc and a white line on the balancer and front case . ran a timing light and it showed right at tdc. i expected some advance.
Oct 5, 2012 at 6:57 PM
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SATURNTECH9
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So it doesnt really run the engine?All the push rods etc were put back in the same places?Everything torqued to correct spec and pattern?you just have a random missfire code not a certain cylinder code?Fuel pressure spec is 48-55psi.
Oct 6, 2012 at 12:28 AM
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MAXAC
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that is all correct except i have 37 psi fuel pressure.
i replaced the fuel pressure regulator, along with gaskets,
i saw it was leaking when i took it off. there was gas coming out of the vac connection
Oct 6, 2012 at 2:53 AM
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SATURNTECH9
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The security light isnt on solid or flashing when trying to start it is it?
Oct 6, 2012 at 3:01 AM