HELP! How probable is it that my LT1 jumped timing?
#1
Staging Lane
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HELP! How probable is it that my LT1 jumped timing?
1995 Trans Am LT1 155k miles. Approaching stoplight and it started running crappy, spitting sputtering,etc. then check engine light on. Cut off a few minutes later and never started back. Got codes 16,42,36,etc. Replaced ICM and coil, no difference. Replace IAC and TPS, no difference. Replace Optispark, No difference. How do you verfiy proper timing without the engine running? I feel like I've exhausted my troubleshooting skills and need help. How probable is it this thing jumped a tooth or something like that? How do I verify that? I'm really needing some help, so anything would be appreciated.
Thanks
Thanks
#2
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#16 is low res pulse your opti
#42 is your ignition module.. check the ground and/or a shortage in the wiring
#36 faulty high res pulse..sounds like ur opti to a ****...u should replace it !
#42 is your ignition module.. check the ground and/or a shortage in the wiring
#36 faulty high res pulse..sounds like ur opti to a ****...u should replace it !
#4
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I know ignition timing is computer controlled but what u could do is take the timing cover off and make sure the dots on the cam and crank sprocket are aligned at 6 o'clock and 12 o'clock postion. !
Last edited by riceburnerZ28; 10-21-2008 at 11:31 PM.
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You will need to have a scanner and see how much timing the computer is pulling, Bring the 1 cylinder to top dead center and make a timing mark on the bottom of your water pump and crank pulley , Thats how I checked mine and it was fine I just used some engine paint so if I ever need to go back and verify the marks are still there