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Unlike the lt1 engine that uses opti signals to tell pcm crank and cam position, your 3800 has a crank position sensor and a cam position sensor that tells pcm what position they are in.

If either one or both are not working correctly, the pcm will fire the engine out of sequence, thus the back fire. You need to consult the 3800 engine section from 98 service manual for testing these.

And when testing the crank and cam position sensor, don't forget that wiring and connectors can cause problems also.
 

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Discussion Starter #24
I replaced both sensors with new ones, and the cam sensor pig tail they had speaker wire for it lol but its all replaced
 

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I could be way off here but i do remember on the older fwd 3.8 i recall seeing somewhere that the little tab on timing chain would fall off and not trigger the cam sensor sounds like you got the car all apart but if the rwd 3.8 is triggered off the cam somwhere else than the front cam gear i could be way off.

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Discussion Starter #27
it runs!!!! it was the fuel!! I poured some out and it didn't ignite so I emptied the fuel tank and put in fresh gas, and pumped it till it smelt fresh then cranked on it till it started!! but damn it smokes lol Ima finish putting the accessories on it tomorrow and drive it around see if the smoke goes away....... we think what happened is the icm under the coils went bad then the car sat for ever then 2 owners later I got it running,,,, thank you guys for your help!
 

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Discussion Starter #29
ok Ima drive it tomorrow but I have a ? when I turn the key forward the fuel pump stays on and if I shut it off, the fuel pump stays on till I open the door? could a fuel pressure regulate do that?
 

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Discussion Starter #33
thanks lol there's 2 and one is missing the lid lol well I drove her today! it he's a miss fire! the number 2 injector is not spraying.....can I use a lt1 injector?
 

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You must be pulling the wrong relay. With the relay out, there's no way the fuel pump will run, unless a previous owner has done some creative wiring. Same for fuel pump fuse.
 
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