FX Gremilins

I think I finally conquered the gremlins. After fixing my grounding problem last week, I’d been driving the rally FX all week and there still was a rough running problem. I could hear it on idle and while driving you could feel it as random hesitating missfires. I couldn’t figure out any pattern either. So through out the week I’ve been swapping parts trying to find the problem. Coil and igniter, no change and in almost seemed worse actually! Throttle position sensor swapped and adjusted to spec, not much change. New spark plugs, cap and rotor no change. Swap plug wires, no change. Grab the distributor, grind down the shaft end to fit (needed because of the ARP head studs), and swap, no change. Starting to run out of easy options! Replaced old brittle fuel injector plugs with new style, swapped injectors, hoped that would do it, but could still hear that occasional stumble and test drive still had that random missfire. Damn it! Then I pulled the air flow meter and measured and compared to spare AFM I had. What’s this? Getting completely crazy different high readings! This has to be creating problems, the ECU is thinking massive amounts of air is gushing through there, all the time! But with this low tech OBD since the AFM is not reading 0 or short it’s not throwing an error.  So after cleaning out the lizard eggs in the spare AFM (sorry critters, two of those were viable) in it went. Car started up, and although it didn’t sound as smooth at idle as the road FX, the test drive went great. The drive out to Waipio to the Okinawa Center dance matsuri was perfect. Drive back I gave it a bit more oomph, it was feeling very nice! Huge sigh of relief!