I have a turbo Miata that I bought already built and tuned by a shop. The car has always taken Multiple cranking to start and would have a tribble idle dip stall issue. It also would have a big hesitation when trying to rev the engine at a stop and when it stopped hesitating it would rev up to like 3k with just a little throttle applied. I looked into the tune and found out that it had Barely any fuel in the bottom of the ve table. So, i gave it fuel, and the idle dip stall issue went away so you could put the car in neutral at any time now and it won't die as rpms fall, and the gas pedal had no hesitation, and you could hold the revs at a low range now with little throttle like a normal car. BUT it now has an issue revving back up when the rpms are falling. Sometimes it even has this issue when you come to a stop, wait a few and then try giving gas to take off. It is very noticeable when trying to rev match and giving gas causes it to die. It still revs nice once parked or sitting there but for some reason it doesn't like revving up when rev matching. I am wondering if i should try to keep adding fuel into higher rpm ranges in the ve table or mess with the ignition chart and excel enrichment. I appreciate any help. The first two are before i messed with it.




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None of that is tuned well. Attach the entire tune and maybe we can help. But the ignition table is retarded in the naturally aspirated areas, and a bit advance in boost, with almost no resolution. Fuel table looks like it might been tuned on a dyno at WOT but nothing else. Weird jumps in VE like it was never tuned.

idle stuff is probably not just fuel and ignition table, looking at the entire tune would help.

 

I attached the original tune before i messed with the ve table

 

Yeah that's all pretty terrible. You're targeting 12.2 at 10ish psi, there's no over boost protection, idle VE is on but just flat lined at 45, idle ignition control doesn't have enough control, you have 10* of VVT advance even at 7000rpm, fan on/off temp is too far apart, those are the big things that pop out to me.

I'm not saying it'll blow up with this tune, but I'd definitely take it to someone who knows megasquirt and have them completely retune it. I'd be surprised if you're hitting AFR targets with that VE table.

I'd be able to judge the tune a bit better if you included a log in 3rd or 4th gear from low RPM to redline.

 

yeah ill probably end up bringing it to get tuned. I went into it thinking it would just be low rpm ve table changes and idle air control valve adjustments. But i guest its worse then i thought. thanks for the help and If anyone knows a good tuner for mega squirt near Raleigh NC i am all ears.

 

Spend $50 on a month subscription to Evans Performance Tuning. Watch all his basic tuning videos and then the MS series of videos. Evan has the best video lessons on tuning, and after watching them all you can't tune your own car, you will know how to pick a tuner that knows what they are doing, and won't get robbed blind.