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-   -   Still having issues with it bucking (https://www.miataturbo.net/megasquirt-18/still-having-issues-bucking-69318/)

Mikelly 11-06-2012 07:23 PM

Still having issues with it bucking
 
...I'm going to have to log and tweak some because when I start the car, let it warm and start driving it, it goes lean and bucks. After about 5-10 minutes, it finally is running what I would consider "properly". Mind you, I'm monitoring and modulating the throttle, but it definitely needs some serious attention.

All that said, this morning at 0530 I was on Rt.29 north heading towarts Rt.66 in Gainesville Va. A little E36 M3 thought he wanted to run from a stoplight. He tried really really hard, and twice from a stop, once from a roll. God this little car loves this cold air.

I'm going to have Surgery on Friday so I'm just not going to drive the car any more until after this whole issue is resolved with my stomach. But once I'm back up and mobile I'll take a look at the last log I posted in the other thread and take a cut on getting the idle stable... Thing is surging really bad below 2500RPM until it gets up to full operating temps.

Mike

hornetball 11-07-2012 01:00 AM

Sounds like you need to tweak ASE, but are otherwise in pretty good shape.

Best way to get ASE where you need it:

1. Make a note of your normal, warm idle AFR. It will probably be just a bit rich of stoich (like 14:1).
2. Now, on a nice cold day start from cold. What you are going to do is run the ASE wizard and tweak the ASE% so that your wideband gives you your normal, warmed up AFR reading.
3. Let the car idle until warm. As the ASE wizard moves to new cells, continue to tweak for the AFR target.
4. Once you've warmed up, you're done. Save your work and enjoy.

Braineack 11-07-2012 10:29 AM

Yeah, needs some extra fuel added in the warm up table to compensate for the cold air, where it's been otherwise unneeded.

upload your latest tune and we could probably just arbitrary get it running a bit better.

John151 11-07-2012 03:43 PM

I experienced similar issues once before - turned out the MAP line had worked its way into a position where there was slight pressure on it. On warm days, the MAP line would get pinched slightly as it became more flexible. The pinch slowed the response of the MAP changes, so aggressive acceleration would result in bucking as things went lean. However, steady cruise was fine. I thought the issue was with AES, until I noticed in a log file that the MAP line trailled behind the TPS line (they generally track together). I felt lucky that I didn't grenade my motor.

Not sure if this is your issue or not, but it gives you something to check in your log file.

Mikelly 11-11-2012 11:09 AM

Might try this later today guys... Recovering from hernia surgery and man I'm sore all over... For those of you with wives who have had "C" sections during birth, that's basically the same type surgery when they fix a hernia... Cutting thru lots of stomach muscle to install a mesh patch. Ugh..

Mike

Mikelly 11-18-2012 08:03 AM

Going to get to this today... Finally feeling "good" 8 days after getting cut on... I'll see what my ASE values are and go from there.

Mike

Mikelly 11-18-2012 05:34 PM

It seems like the tune is much happier when I switch the wideband to the Innovate LM-1 instead of my UEGO. I "think" I have the car dialed in better with the current settings, but time will tell. I may drive it in to work tomorrow and see how it does again.

Mikelly 11-23-2012 06:35 AM

Well it's back.. This is intermittent and something I'm thinking more mechanical and not software related. I'm going to check all the vacuum hoses and then consider replaclng the Map sensor.

Mike

Braineack 11-23-2012 08:15 AM

log the event, and ill take a look at it. could be a number of things. but i sitll think we need for work on the colder temperature related settings.

Mikelly 11-25-2012 08:58 AM

I sent you an email with the file, two log and the tune. However, this Morning while its colder I may try to log some more with it bucking in the colder air. One thing I noticed is that the AFRs are spiking at 16-18 in the logs. No clue "why"... It just goes real lean, and then comes back to normal. Very brief, but still...

Mike

Mikelly 11-25-2012 05:08 PM

Braineack is the man, Again, as usual. The file was causing the car to go way lean, but I was able to copy the settings from the file he sent me and I was able to duplicate the tables, and make the changes, as well as correct an issue with the warmup wizard.

Might take the laptop with me in the morning and just autotune the whole 1.25 hours to work.

Mike

mellowout 11-25-2012 10:14 PM

care to share your fixed tune?

Mikelly 11-26-2012 07:13 AM

I'll post it this evening.

Mike

Braineack 11-26-2012 08:46 AM

One big problem was that the warm up wizard was dropping below 100% around 140°F. That was causing the map to lean out as the temperature was reaching 170°F.


Another thing I changed was the AIT corrections table, which was still based on the MSPNP basemap for an NA. It's great for an NA that sees really high intake temperates, but not for a turbo setup for with a FMIC. I'm emailing another map that compensates in the fuel map for the reducution of AIT corrections. Your old map was already adding 5% more fuel at 50°F intake temps, so when I leveled that off, the fuel map was too lean. On your log you were averaging 10% fuel being added based on the intake temps...which is silly.

Mikelly 11-26-2012 06:50 PM

Scott, I'll load it up over the next day or two and drive the car. I'm knocking down about 27mpg right now, and the car seemed to run ok. I will def. want to do the VTPS on the car. A little nervous about that because the documentation is a little misleading in the various threads... Probably wait until the Xmas holidays to knock that out.

Mike

Mikelly 11-27-2012 05:32 PM

4 Attachment(s)
OK so hot off the presses is the latest and greatest tune, and log. I just loaded and drove around and logged it over the last 45 minutes.

Mike

Mikelly 11-28-2012 07:31 PM

Finally got the chance to put the 150miles roundtrip in it with this tune today. Ran smoother, still knocking down about 26.5-27mpg. Of course that's with getting on it a little bit, but it's pretty fun to get into it. Smoother on cold start-up, and smoother in parking lots.

So far so good!
Mike

Braineack 11-28-2012 07:44 PM

Ill take a look next chance I get. But sounds like I got it running much better again?

Mikelly 11-28-2012 08:05 PM

Dude it's running MUCH better. I'll maybe cart the laptop with me tomorrow and let it "self tune" on the way home. 75 miles of driving will give me plenty of time to "VE tune it".

Mike

Mikelly 11-29-2012 04:11 PM

Drove the car for well over an hour letting VE do its magic. Seems like the fuel economy is "up".

Mike:party:


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