*update* no fire with popbacks/backfires
#22
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I too had this exact same problem when my new motor was installed this past summer. I can almost guarantee you it is the coil pack plugs. If you pull back the wrapping on each individual coil pack plug you will find different color wire combos. I cant find a wiring diagram but someone on here might be able to find one and tell you exactly what color combo goes to to which cylinder. I had mine *** backwards, my passenger side harness was plugged in so that the plug that was supposed to be at the front was in the back and so on. This caused the backfiring and etc. As soon as the harness was turned around it fired right up.
#24
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Check to see if you plugged the coils/harness in the right order.
When I did my H/C install years back, I completely took off the part of the harness that connects to all 4 of the coils on each side. Well, when putting it all back together I had them backwards. The car would crank, but just pop and backfire. I know it only plugs in one way, but if some reason its twisted, you can have the plug for #1 on #7 and the plug for #2 on #4 and visa versa. if that makes since.
When I did my H/C install years back, I completely took off the part of the harness that connects to all 4 of the coils on each side. Well, when putting it all back together I had them backwards. The car would crank, but just pop and backfire. I know it only plugs in one way, but if some reason its twisted, you can have the plug for #1 on #7 and the plug for #2 on #4 and visa versa. if that makes since.
After that was corrected, runs like a champ.
***where were you when I spent 2 weeks on trying to figure this out? lol
#29
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Hmm i was going to say your #1 Piston wasn't on TDC Compression stroke. Usually if it backfires intake your #1 Piston is on Top Dead Center Intake stroke. Exhaust stroke = backfires out of exhaust. #1 needs to be on TDC compression to fire up. But glad you figured everything out.