04-13-2016, 09:54 PM
Join Date: Feb 2011
Location: Minot, ND
Total Cats: 17
2000 Miata brain built MS3. Idle issues/ give my tune a look?
I'm in the midst of an insane work week. (waking up at 3:15, work from 4a.m. till 7p.m) and can't get my mind around an issue my car has developed.
I'll be brief for this first post and come back and edit when my eyes are not straining to type this up.
I have a 2000 Mx5 with an air research t3, rx8 428cc, and a recently swapped in 99 1.8 with great compression and lower miles than my other tired motor. *also running open downpipe till I get my exhaust welded back on.
I used to run a brain built ms2 diypnp. I've been running a brain built ms3diypnp for almost a year now.
*I'm not a pro at megasquirt by any means.
My miata has always had a "hunting idle" situation. Once it is warmed up, it'll sit around 900 rpm, but it'll bump from 850 to 950 in a very slow rep. The downfall here for me is that my a/f will be around 14.5-14.7 but during it's drop down and coming back up, it'll hit 14.0 and rise to 15.7.
This is at every stop light, and every idle scenario once the car is warmed up.
And now with my new setup (motor, trans, turbo, IC, and turbo manifold, along with the bigger injectors) When I decel or "engine brake" and start slowing for a stop and push the clutch in, the rpm's will 8 times out of 10 drop all the way to 0 and stall the car. Wideband is reading lean in decel like I thought it should.
Or if I just simply take the car out of gear and come to a rapid or slow stop, it'll almost die, catch maybe 500 rpm, try to idle, and then die at 0 rpm abruptly.
I've been working this hectic schedule since sunday and won't have a day off till hopefully Saturday, I'm posting this so I can have something to read when I get off work.
I've googled a few things but I am stressed for time and sleep. Please only help if you have the time. If not, no offense is taken. Just wanted to give this a shot.
I'm attaching a file of my current tune. It is not anywhere near done yet. I've only been trying to get a proper idle and cruising capability for a total of 2-3 hours before this work week started. Thank you
*I have not changed too much from the base tune I was sent with the MS3. There were some hiccups when I first got it: alternator control was not turned on and I had to open the casing and turn some **** to get the tach to read properly.
I'm hoping there is something stands out as a red flag with my idle setting, closed/open loop, tpsdot, any ego corrections ETC. Thanks again for any input here!!