So it’s an 89 Galant that’s misfiring. My question is, is the fuel system on these hard to diagnosis? I’ve heard a lot of these early fuel injection systems were a pain in the ass, but I don’t have much experience with pre 90's FI.
The owner thinks it’s a HG, but I don’t really know how that’d cause a misfire. I’d think it would be an ignition or fuel issue. Or even a bad exhaust/vacuum leak.