Car initial startup/idle issue
 

I am having an issue with my startup. Previously i would have to hold the accelerator pedal down on startup to keep the rpms up for 30 seconds before it would idle. Now I start it up and it will die the first time and then the second or third time it will start and then idle poorly. I cannot figure out what to do. Here is my my log and msq if anyone could help me. I just rechecked timing was at 10 when on fixed timing. There also seems to be a slight misfire or hiccup at idle. I haven't noticed this before MS install. I just changed fuel req from 12.9 to 13.2.

Thanks in advance,

Ben

You should add a signature block and show your list of mods. Your user name suggests you have a 1.6, but your tune shows 1839cc. When I had stock injectors on my '99, my Req Fuel calculated out to 12.2. How did you get 13.2?

Il'll change my signature block now. That name was from a 1.6 turbo build i did back in 2014.

lol I had it set to 12.9 as it was stock in the ECU from reverant. I saw online from what i think was braineack said 13.2 was correct.

1990 miata with 1.8l flyin miata swap (95 motor), k0422 turbo (mazda cx7), stock 1.8l injectors, ebay intercooled, DW 255lph fuel pump, 5x11x22 magnaflow muffler with no cats, MS2Extra/Enhanced by Reverant. There are some others but they are irrelevant to my engine.

tune your startup settings.

I have been trying but I haven't been too successful. I made logs this morning but the attachment button isn't showing up so i cannot upload them. It started up the second time this morning. I changed the req fuel back to 12.9. This is the number that the fuel calculator in megasquirt has given me.

Here is the file. It is too big for the site.

https://drive.google.com/file/d/1egB...ew?usp=sharing

since you have to hold the throttle open to sustain running, the first thing I would start tuning is the cranking duty table and initial idle duty tables. think about every car you ever start, they idle up after initial startup and then slowly work down -- you need to mimic this WITH THE TUNE, not your foot.

then you probably have a completely untuned warmup table as well coupled with a poorly tuned VE table, and why youre having difficulty running, where you need more fuel at idle when the motor is cold, and holding the throttle open is probably putting you at a better spot in your ve table.

Once the car is warm it idles mostly normal (with some small hiccups/stuttering every once in a while) I adjusted the cranking rpm to 400 from what I saw you said in another post. I will try to make some more adjustments after work. I have an issue when I burn to the computer the car tries to die, is that normal? Thanks for the info.

with ms2, yeah, that was annoying.

I changed my Idle Cranking Duty/Steps and got it to start at about 1100 but immediately dropped down to about 850. I cannot find where you change the base rpm at initial startup so it will stay at 1100 and then idle down after a specified amount of time. Is that the idle warmup duty/steps table?

Does the MS have a place to set injector response based on voltage? and if so did you set that?

I don't have an MS for my EMS I have an Hydra. But when I changed to different injectors I had to change the setting for the injector response. It would not idle properly until I did.

it's the crank-to-run setting. you're only not using closed loop idle -- this will cause much havoc when the temp and/or load changes.

your prime pulse table being zeroed out is odd.



https://cimg7.ibsrv.net/gimg/www.mia...ca884dbe44.png

you're also not using adaptive timing with idle control, which coupled with closed loop makes idle better than stock.

So I should change all my parameters to what you have on the right side in yellow, change my warmup enrichment to match yours and use adaptive timing with idle control? I can do that on my lunch break.

close loop requires more tuning than a lunch break, and I didn't post those settings -- but you can d/l one of my diypnp basemaps and compare to yours.

Ok I can do that. I figured my spark plugs might be fouled because it hiccups at idle also so I changed to the recommended ngk vpower gapped at .025. do these old ones look normal? They have about 1000 miles on them.

https://cimg5.ibsrv.net/gimg/www.mia...2739cf919d.jpg
https://cimg4.ibsrv.net/gimg/www.mia...2511979d20.jpg

those look prefect imho.

For some reason after changing some settings my car idled at 2200 rpm. I then turned it off for 2-3 minutes and came back out to start it up again and it was a normal idle rpm without changing any settings. I drove to the store to get the plugs and it stayed in a normal rpm the whole time. When i left the store to go home my car idled at 1400 rpm and did so until i got home. Why is it so sporadic without any input from me?

your tune is telling the idle valve to stay open at a particular value based on clt temp and nothing else.

The weird thing is that my coolant temp was 178 degrees but idling at 1400. The bubble that i arrowed to was glowing green.https://cimg9.ibsrv.net/gimg/www.mia...ab2717c8e8.png