[Mancino]

I recently got my car running on a Speedy setup. Had some bugs that prevented me from starting, but all that's worked out now. The next problem I've been struggling with is starting. Mainly cold start. The car just won't start unless I give it some throttle. When cold, it takes longer. Sometimes a few attempts to catch. When it does attempt to start, it bucks a few times and quits.

I've tried going both ways with the cranking enrichment and ASE, but it doesn't seem to help. Sometimes going too high, it seems to flood the car a bit. Then I need to crank more to clear it.

Any quick suggestions you guys can think of? Maybe it's a combination of things I don't have quite right?

[LPG2CV]

You need to post your tune, and a log of it occurring

[Mancino]

Here is the tune that seems to work the best right now...it's still in the works obviously. I don't have a log yet of the event. I can hopefully get that tonight when I have a bit of time to play around.

[PSIG]

Tuner tip: Log everything. It is your window into the engine, what it's doing and what it needs. You can review and analyze the log on TunerStudio (good for settings and adjustments) or MegaLogViewer (much better for tuning analysis and diagnostics, so you know what to set in TS).

Before tuning cold start, you must set a good tune for warm running (the baseline everything works off-of) and warm starting. Here is a first-start outline I did to help with this: Successful Initial Start. At least initially, the cranking, idle and high-idle areas must be spot-on before tuning cold starts. Extra functions such as closed-loop idle should be turned off so they don't confuse the tune or the tuner.

Here is one description I gave previously on tuning cold starts after tuning warm start, taking each startup/warm-up function as a separate step:

... Remember, starting is a series of events beginning with priming, through cranking enrichment, transitioned by ASE, to WUE. Taking it in clear steps one-at-a-time usually makes tuning simpler and more effective. When you get one working well, move to the next. Begin with a very good warm-idle tune and warm restart, and on the next cold start adjust each event control to best values for immediate and solid response. If it responds well but then quits along the way, that's no problem, and just indicates you succeeded with that adjustment and need to adjust the next event control.

For another example; some like to zero all cold start/WU settings (no change from warm-start) so each step in tuning is very clear, and the engine only runs as far as steps have been tuned. Then for example, key the power ON twice instead of once in order to double-prime. Did that cause instant firing on the first rev (after minimum sync) like when it's warm? If not, key it again for more fuel until it does. If that was 3ms, then set prime at your cold temperature for 3ms and test, then set cranking for extra fuel until it catches and gains to above cranking rpm then quits. When it does that add enough ASE to carry it for a few seconds then quits. Good? Then add WUE until it continues running. Tweak WUE so it is solid and strong as it warms.

Use whatever tuning scheme like that you can get your head around, and follow your steps methodically. Most find that once they get the first couple results, it all begins to make a lot more sense. Watch your logs and learn to interpret what the engine is telling you by its responses. This is tuning!

David

[Mancino]

Thanks, PSIG! That's a good write up. It looks like I'm putting the cart before the horse then...Admittedly, I'm very green to Speeduino. I figured I had the car idling and running pretty good so I wanted the start up to be easier and jumped right to it. I still need to work on other areas.

[Chris Wolfson]

What kind of idle valve do you use? You need some extra air to have an instand cold start.

[tigerstyle]

That image is 8MB, bit excessive for a forum

[Mancino]

What kind of idle valve do you use? You need some extra air to have an instand cold start.

I'm not using one at the moment. The wiring is in place to run it though if needed.

That image is 8MB, bit excessive for a forum

Not quite sure I understand the issue...what exactly does it do to the forum?

[PSIG]

I'm not using one [IAC] at the moment. The wiring is in place to run it though if needed.

That's fine, as initial warm tuning should be in stable conditions and the IAC is often disabled or capped for that. Chris is saying when you move to tuning cold start that you will likely need more air (again, stable, so typically in Open Loop mode) to get the additional air often needed for stable startup.

That image is 8MB, bit excessive for a forum

Not quite sure I understand the issue...what exactly does it do to the forum?

He's saying that the image is much larger than necessary for the detail, and it makes for slow load times on slow connections, large data use, etc; so resize or compress your large images when possible. It's just a consideration thing.

[Mancino]

Ok, I'll keep this in mind. I tuned a bit more last night. I got a better warm start, but it still needs work...one thing I noticed was the taper time to ASE. It helped when it was increased

I definitely don't use forums that often as you can probably tell . I didn't even think people considered that when uploading pictures. I thought the uploader usually set a limit to follow on size. One particular forum I use, they encourage higher quality pictures so details can be seen better.