DIYPNP starts then stalls when warm
 

I have a 95 with a 1.8 that has had a DIYPNP on it for over a year. I just installed new flowforce injectors about 9 months ago. I have noticed that the car seems to start and run fine until I drive it to the store or something quick. After about 10 minutes of sitting in the parking lot, I will come back and start the car and it will start, and then stall immediately. It will do this until I give it throttle for a couple of seconds and then it is fine. Subsequent starts are no problem unless I let it sit as described. I have logs of the car doing this and have played them so many times, but can not find anything strange except the AFR, but I think it's lying to me because sometimes it says 7.8 before and after starting the car for about 10 seconds and then picks up the actual readings.

I had no problems that I could remember in the cooler months, or before the injector install. The reqfuel calculations are correct as far as I know, and I've tried messing with the ASE, and disabled the MAT during ASE - nothing seems to make a difference. Can someone point me in the right direction?

More ASE, for longer taper at 180* CLT and up. Taper must be long enough until the EGO can help control AFR. As you noted, it takes some time before the WBO2 sensor is working (I'm guessing an Innovate brand). I'm using 1100 cycles ASE Taper at high CLT.

Also, add a longer time to the transition from Start to Run IAC percent, if that is possible with an MS2. This will hold the RPMs up after the start in order to let Closed Loop Idle engage. Otherwise, the lean mixture will keep the RPM's too low for CLI to come into play. 3 seconds should be enough.

Lastly, have at least 10% EGO authority in the idle range.

how about preventing the MS from randomly pulling 23% of your fuel total based on air temps.


Using EGO to solve shitty tuning practices, is a shitty tuning practice.

OUCH

:)

look at his log, his ait corr% is 77%. even if you gave EGO 10% (I actually used 15%), he's still be injecting 13% less fuel...

obviously his MAT based corrections are actually incorrections.

Scott,

I agree. I also admit that I did not look at tune, assumed general correctness, and then presumed that the issue was injector heat soaking, rather than MAT issues. Looks like MAT correction setting in 3.4.2 on MS2 is same as newer MS3, which is good, if set correctly.

Holy mess... I set that table long ago like day 5 of tuning. It's back to stinking default... that's the problem with set it and forget it. I actually forgot about it. I must've done something stupid when loading maps after getting the injectors in. I was wondering why auto tune wanted to change my fuel table. Jeez

For now, the hot start issue is solved by really jamming up the ASE and Taper. In the future it'll be done with a correct tune and and an adjusted MAT.

Thanks for the kick start!

put it at 100% flat, until your fuel map is perfectly tuned, and only tweak the MAT corrections table if you actually need it in extreme temps.

Thank you, Brain.

And thanks to DNM for the temp fix. It helped a bunch, and actually put a bandaid on until I can get it back.

Can you post your ASE curve and taper? Having hot start issues here as well. Think I've got an idea of what they should look like but just was curious what worked for you.