Drove about an hour with the trailer to pick up some furniture. Sweet opportunity for datalogging and tuning!
ISSUE #1 – SPARK TIMING: Wow this thing has some knock issues under load in areas I haven’t been driving in. Maybe the factory tune just leans on the knock sensors for those periods, that way you can still have good spark timing when unloaded.
I did some research into some P59 tunes in the Sloppy Mechanics Tune Cabinet, and found they really pulled a lot of cruise timing out as well – they were running what I was ending up at.
I also decided to “un-scale” the tune. A “scaled tune” changes things so you can have a spark table that goes higher than 7psi boost. It’s telling the PCM that the injectors are half the size and making the VE table half the size (among other things). The PCM determines where you are on the spark table by how much fuel you are consuming, so “saying” you are using half the fuel puts you in the middle of the map instead of the end of it.
I will say that I think it’s a lot more “stable” now without the scale. The downside – the spark table is maxed at 7psi boost – but if you set it for 14° in the last cells, you’re pretty good to run 15psi boost from there on.
ISSUE #2 – SIGNAL STALK CANCEL MECHANISM: One of the signal stalk cancel mechanism springs broke inside the column and honked the horn for me. And the signals didn’t cancel. I fabricated a new one (top) out of 0.045″ round (RC Servo linkage wire?), and it’s back in business.
ISSUE #3 – WIPER “PARK”: It seems these wipers DO park. Not sure how I lost the case ground, but there we have it. I really can’t get at the wiper motor easily (in the way: air ride gauges and hoses, PCM, and AC unit), so I ended up putting a hose clamp around the motor to hold an electrical connector to the case with a wire running to ground.
ISSUE #4 – WIPER SYNC: The wipers were a bit out of sync, so I took the cowl panel off and messed around with the linkage. There is no real evidence of worn out anywhere, but the rods can be “tweaked” and bit which moved things around. I took the lever arm off the motor and bent it about 3/16″ more and reinstalled it. This would slightly shorten the driver’s side “throw”, and it “looks” better, but I’ll know once I’m out in the rain again.
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