MS3Pro tuning help... AIC dead?
 

Hi Yall,

1996 miata 1.8 bored over .5 with forged piston and rods, +1mm valves, intake exhaust cam mod, kraken manifold and turbo managed by a brain built ms3pro pnp

Im back. Thanks for all the previous help getting my basemap and fan working. I was finally able to get the car started and driving. I was able to get a bit of autotune and logs.

My current issue:
My AIC valve seems to not function properly, when performing the idle valve test from 0 it will idle at around 700rpm then at 27 steps it will stop raising the idle then will stop raising the idle again at about 47 steps and after that it will keep raising the revs up until around 4k all the way to 100 steps. This presets a problem for me that makes it difficult to start the car when its warm, I have to modulate the throttle a bit and hold the rpms up for about 15 seconds for the car to get into idle. Other wise the car idles well, with fluctiating idle between 14.3-15.0 ish AFR.
Another issue that I ran into was on the highway going about 60 in 5th gear and then suddenly the car started to surge and the AFR went way lean. Then the car died at the pull off ramp and would not start again. It would catch and stall out right away. I was finally able to give it gas and limped back to the shop. At every stop light I had to keep the rpm above 1000 to keep it from stalling. Most of these issues are in the log.

Attached are the log and current tune.

All help and suggestions are greatly appreciated.

Thanks

So you have a dead spot from 27-47 you’re saying? That’s most likely a bad idle air valve, but if you’re testing with a steady 700rpm idle and then suddenly it won’t stay running under 1000, it might be a different problem. IAC shouldn’t do anything cruising down the freeway, it’s usually shut, so that’s a different problem. Even if it randomly opened, MS would simply register a change in MAP and follow your fuel map, and the car would accelerate. Not go full lean and try to die.

so use 47-100 and close the idle air bypass screw that's fucking up your idle...

I will try that today after work. Thanks