Ok, so I've had an SAFC2 on the car for a while, and had an "ok" fuel map done, but rather rich...
Anyway, I thought to try a CA20E TPS (I'm fairly sure that is what it came off of, might even have been a KA24DE TPS but the throttle body it was on had a vacuum assisted opening valve on the throttle linkage to keep it open, looked more like an "older" '80s style fix to throttle problems). Anyway, I switched it over and wired it up... I also had a lose unused plug on my wiring harness that matched up to a secondary plug now found on the TPS, but I'm not sure what its for (looks just like new style O2/Coil pack plugs, 2 wire oval in shape). That's the TPS on a Z32, but it wasn't there before on my S12, so I didn't tinker with it yet... but anyway, I finally got it wired up went to drive it and tweak the fuel maps and all of the sudden I'm running crazy rich under throttle and backfiring... also noticed when I got on it hard right around 4500 it just cut out, I'm like wtf... so I note the SAFC2 around that amount of throttle and the TPS reading changed from 100% (which it normally ALWAYS says) and it said 0%. It was actually working, but backwards... argh. So I tired changing the car type to down throttle and it now read right, but I couldn't get the fuel maps right and I had to reduce the negative corrections I'd had below 4k. Previously it was like 20% removed, and now I was down to 7% just to stay above 10A/F at cruising, let alone throttle, then even the high throttle map required lowering to 7% but after 4k it went CRAZY rich, like 7A/F.
So, after trying for a while, I resigned to removing the ground wire (new TPS actually has 3 wires, where the old S12 one I had was a 2 wire in a 3 plug). When I removed the ground wire, and changed back to an up throttle type, it went back to 100% throttle at all times, and I just adjusted the fuel map accordingly. Right now I'm running 11-12 A/F (10s occasionally) at WOT, but... its really jerky and putters really badly under deceleration... =( so, I have a trade off here... either EXCELLENT power and great A/F at WOT, but bad cruising/deceleration, or good cruising/deceleration, with "ok" WOT... I'm sure you know which I'm staying with for now...
Few things I know I need to do
#1 Change spark plugs (I'm currently just using copper Densos, and I'm sure I've fouled them somewhat)
#2 Change spark plug wires (I'm just running a cheapy set of Advance Auto Wires... needed something to get the car running)
#3 Jump the coils so they both fire... (I read the posts about this, but I can't understand exactly what I'm supposed to do, do I jump both positive and negative to the secondary coil and leave the original plug disconnected or just tap it into both wires and leave both connected?
#4 CHANGE TO A DE HEAD!! I hate this E had.. =( I saw a new Pulsar at the local yard and I think it might cost me <$100 to get the entire head and intake manifold, cams and all... so I might try for it... see if I can't swap over... only problem is then I'll need a new wiring harness and DET ECU... had one, but I sold it a while back... D'OH!
#5 Buy a DET T2x stainless manifold off eBay (they're like $350 at the moment for equal length, hopefully they'll come down a little).
Joy joy joy... anyway, just wanted to rant... I had a fuel line blow on me Friday night outta the blue... drove home from work at ~5pm, parked it, went to get food at 9pm and its running all weird... cut it off and pop the hood and everything is all shining on the top of the engine... joy, fuel everywhere... #2 injector BLEW A HOLE in the side of hte new rubber fuel line... it was like maybe a couple months old... =) Anyway, I'll shutup now, I've got other posts to write...
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