hi everyone! i have a 89 single cab chevy 1500 that ive recently put a 94 LT1 and 6 speed in. the swap has went great so far and ive actually driven it a couple times. starts up great but it deffinately has a miss on at least one cylinder. i put new plugs and taylor plug wires on it when i made the swap. when u go to excelerate it will backfire 1 time and it kinda feels like its lacking power. i pulled the plugs off the injectors 1 by 1 to c if i could tell any distinct sound difference in each cylinder and 2 of them didnt change the rpm or sound of the motor any so i swapped them out and it still does the same. i checked the injector wires and made shure they were hot and they were. i put a timing light on each plug wire and made shure they all were firing and were consstant,and they were. im starting to wonder if its the ole opti... but any help with my situation will be much apreciated,its my only way of goin and ive been without it now for about 4 months. THANKS AGAIN!!!

 

Codes?

Fuel pressure?

 

Well unfortunately I haven't had access to a scan tool and fuel pressure I haven't been able to check either,it has a good high flow fuel pump in it though so I haven't really thought that would b a problem. I had a new wiring harness and the computer checked at street&performance and I have went threw all the wiring and everything very theroughly.

 

We've all seen brand new pumps fail, and we've all seen the connections in the tank fail or come loose.

 

True! That's going to be the next thing I look into I just thought maybe with opti being so sensitive on these motors that that would be what my symptoms are saying ya know? It idles good but as soon as u give it any gas or put it in gear and start to excelerare if it gets too much load on the motor it backfires. And if it backfires and then dies then u will have to pump the excelerator to get it to fire back up. But then it will idle good again. When I drove it it ran good except for a slight vibration in the shifter as though it was a slight miseries and if I got it ip in rpm say 3,000 or so it would backfire maybe once or twice.

 

My bad on the misspell when I said a slight vibration in the shifter as though it has a slight misfire.