Forgive me if you may think this is an inappropriate post, but i have been baffled by this problem for over 2 months now and im at all loss for what it could be. Ill explain my full situation:

So i broke my rear end april of last year, and had it sitting around until i finally had time to tear it all out and fix it, but over the course of time from letting it sit, it seems my car just went downhill. It still has yet to be running smoothly, and can not figure out why. all of my mods can be looked upon at www.fquick.com/zyalater but basically here is the case. I could not start my car back up and have it running smoothly, it was horrorificly bucking and missing like it was running on 5 cylinders. So i washed out the tank, put new gas in it, and it was still bucking. ok, fouled plugs? changed em to NGK TR555's, still bucking AND missing upon idle now once it would sit and load up(it would idle fine before with AC delco platinum plugs). replaced the plug wires, they are fine. checked for spark in the opti, that was fine. held a thermometer to each header primary to check the temp, and cyl. 7 was not up to temp compared to the others, so we swapped out my 30lb. svo injectors and put stock ones back in, but now cyl 6 was the one not operating correctly, so im glad its not an internal compression issue, but i am assuming its a fuel issue. (Please keep in mind my car is a 1993 with batchfire and a mail tune from PCMforless and once again all of my mods are on my car website) I need some quality input on this matter please. I am working with a GM ASE certified mechanic who worked for Brady's High Performance in Lancaster, PA and we are both at loss for what the problem could be.

 

I could be wrong but my dad and I had run into problems like this with street rods since the engines sit in the shop for 3 to 6 months without being fired and who knows how long they sat before we bought them but to make a long story short all of ours were just stuck injectors not firing maybe this will help.

 

thats my number one idea i am assuming that is wrong, but when the dropped cylinder jumped from number 7 to 6 after swapping my 30lb. svo's to the stock injectors really threw me off. we checked the pulse of the injector clips and they are all pulsating so I know its not an electrical issue at least also.

 

I saw that you had said that but with the stock injectors sitting for so long I automatically thought that now the one on #6 is stuck. We always just tapped on the injector that wasnt firing with the handle of a screwdriver while the car was running and eventually the injector would bust loose. Hopefully this will get you back on the road!

 

Let me know if this works for you or if it happens to be something else let me know what it was. You can never have too much information! Thanks

 

+1 on the injectors but if not that then it almost smells like a Opti issue