Mods in sig. Went to get dyno tuned and having weird misfires in all cylinders. 1 run it would be 6-18 misfires in cylinder 3-4. Moved coil packs around then it was misfiring in #1 cylinder. Having probs from a bad batch of parts i bought in a TAG group buy awhile ago. Bought the 2.79/60 lb inj./plugs/mail order tune from them.
Found out they gave me BMW spark plugs, and Bad insulated injector harness.
Changed plugs to 1-step colder gapped at 35 and a new harness. The question is does anyone think it may be the coil packs or do you think since all the other parts i bought from TAG were garbage that my 60 lb injectors might be causing the problem? Thanks