Idle all screwed up
 

When I first started up the car running MS, it idled just fine. After my little no start issue, now it idles around 1200-1400 and moves up and down between those numbers. When it revs up to 1400, the car misfires and the rpm's drop back down to 1200, etc. Also, on cold startup the car revs up to 2800 and stays there for a couple minutes. How do I fix these things? Under idle control, cold idle is set at 1400 but it seems to want to double that.

Car drives fine down the road, no issues there. If someone can take a look at this MSQ and yell at me that would be great. :laugh:

reset your timing, you're missing the trigger angle addition (+22.5)

When I first timed the car, if I added the addition, the car would freak out. The idle would really move up and down then.

pretty sure it needs to be set that way.

Of course your trigger angle with vary. Mine is 56, yours looks like it should be in that range as well. You are nearly compensating for the lack of addition.

EDIT: All your tables and constants look good.

Oh yeah, duh, swap idle to PWM.

This is what my settings look like...

Attachment 207013

Wow, my settings are way off from yours. Wonder if I should try them out...

You're NA though, right?

yeah, N/A NA

EDIT: shouldn't make a difference, and we're running the same injectors. Only difference I see is that you are running variable throttle position sensor accel enrichments. I won't be doing that until next week ;)

Hmm, maybe I'll make a duplicate MSQ and give them a try. I'll see if I can reset the timing this weekend and put the +22.5 addition in.

Here is mine if you want to poke around and see what else you may be missing.

Awesome, thanks. Weather is shitty here through saturday night, so the car will stay in the garage. I'll give some adjustments a try when it clears up.

Not necessarily - it needs to be set so the basic trigger angle is between 50 and 89 degrees and the timing matches, but you can accomplish that with or without the trigger angle addition on most Miatas depending on the factory CAS tolerances. You will need to be sure your base timing is correct.

Ok, understood.

So if I took the trigger addition off, mine, at 56 degrees trigger angle, would still fall in that range at 78.5 degrees.

I assumed above that he was basicaly compensating for having no trigger angle addition.



So what about the idle settings?

He has basically nothing setup there in his .msq.

change the algorithm to PWM and change when to use to closed loop.

also change your dwell settings to 5.5 cranking and 5.0 running, should fix your misfires.

Thanks guys! Think I'm starting to get the hand of this stuff now.

Ok, took the car out for a drive. The misfire at idle is gone, but it will not idle any lower than 1100-1200. Definitely idles better though. Finally got a few pulls near redline @ 12psi and the AFR is in the 11.8~12.2 range. So I will be sure to add some fuel up top.

First drags of the season are in two weeks, so gotta get it tuned enough for that. Seem to be on the right track. :D Thanks for the help guys, and any more insight into the idle thing would be great. :)

Ok, so I switched to gospeed's map, imported my spark and fuel tables, changed the spark settings back to mine, and the car idles great now. However, after shifting the car bogs and it doesn't like boost at all, so I have a few things left to do. :noob:

Yeah, that map hasn't been tuned for boost at ALL!!!

Sorry, thought I had made that clear.

I'm still working on my overrun tuning, so let me know if you figure out what I'm doing wrong before I do.

Glad to hear things are working out!

I know that, hadn't really driven it but around the block, and barely went into boost but a tiny bit, which it didn't like. (knew it wouldn't) I did spend some time last night swapping over some of my boost settings, but the car didn't want to idle this morning for some reason, so I switched back to my old msq with the bouncy idle. Boing...Boing...

Oy.

why not just copy his idle settings to your working map?