Difficult cold start help
 

2005 MSM with a MS3. I have had the car professionally tuned and it runs great once started and the AFR settles down after warm. But it is difficult to start when stone cold. It takes many cranks and sputters a few times before finally starting up. If the engine is warm it always starts right away.

It's been a long time since I've messed with Tuner Studio - life, kids, job, etc.- but I'm sure it will come back to me. Can anyone take a look at my tune and let me know if there are some obvious settings that I could tweak to improve my cold starting issue?

Thanks.

I'm kind of taking a stab in the dark without a log, but try the attached tune. Made some idle changes I typically use, maybe it'll work, maybe it won't.

Looks like they did a decent job, I typically don't like the 15+afr in cruise, and it's a shame they didn't tune it with incorporate AFR turned on, but other than that, looks like they tuned knock control, made MAT retard actually safe, and fixed a bunch of other stuff that's shit on some base maps.

With a log of it starting cold, I see see what your idle valve and fueling is doing.

Hi SpeedracerIndy! Are you running aftermarket injectors, and if so, what size are they?

@curly

Because why? pollution, or some other reason?

DNM

100% unjustified paranoia. I just know lean cruise can burn up pistons over time, is that 15:1? 16:1? No idea. When I tune, I don't know if the longest freeway cruise is going to be 10 minutes or 10 hours. It spooked me a bit when a customer picked up a miata after a tune, and sent me a pic from 3 states over the next day saying "car ran great, thanks again!". I had no idea he was going to pick it up and immediately put 1000 miles on it. I was glad I tuned to 14.7 and not 15.5. IIRC, that same customer said he got 26-28 mpg, and at that mileage I don't feel the need to tune for more.

TLDR; If you want to hypermile, get a Prius, IMO.

Thank you!!!

Car is on stock injectors.

Was planning on loading up this tune this weekend to try out but realized I don't have TunerStudio on my new computer and my company won't let me install it. :mad: So now I need to locate a computer... I'll report back when I get it loaded, and we have some cool mornings coming up so good opportunity to test cold starts.

Thinking back on when I had this car tuned, I had a problematic AFR set up. It was an innovate sensor and was showing erratic readings. I remember the tuner having trouble with it so maybe that's why he tuned without incorporate AFR on? Does that make sense. I have since installed a new AFR from AEM and it has always worked fine.

When I locate a computer I'll get a log of cold start to share.

Here's a cold start log from this morning. This is with the tune shared by @curly . The changes made a big difference, the car started faster and reached a stable idle relatively quickly. With the previous tune I had to crank for quite a while before it would catch, then it would sometimes stumble and die. I killed an AGM battery with so many hard starts this spring.

Let me know if you notice anything in this log that is of concern. It looked pretty clean to me.

@curly how do I compensate you? This would have cost me many $$$$ to take to a tuner, which I don’t have time for. I was prepared to put the car away until my kids were out of college but now it’s drivable. Ok, so that may be a bit of an exaggeration, but I’m still very appreciative for your help.