After-start idle control (cold)

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Re: After-start idle control (cold)

Post by turbo conversion »

Jim_Blackwood wrote:Yes, it is rich. I do intend to lean it out.
The thing that puzzles me after looking at your ve and afr numbers I would expect it to be lean not rich, they are very low.

David
1976 Datsun 280Z L28ET Garrett GT35R T3-T04E stage3 50 trim 63 A/R housing custom grind cam 2000-6000 rpm 440cc injectors intercooled 18 lbs. boost
3" exhaust turbo back LC-1 o2 sensor Hallman manual boost controller EDIS 6 ignition batch fire 60mm throttle body 5 spd T5 borg warner 3.54 lsd
turbo conversion
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Re: After-start idle control (cold)

Post by turbo conversion »

After looking at your msq again I think your ase enrichment is set to high.

Try lowering then, here is an example of what mine are set to.

David
1976 Datsun 280Z L28ET Garrett GT35R T3-T04E stage3 50 trim 63 A/R housing custom grind cam 2000-6000 rpm 440cc injectors intercooled 18 lbs. boost
3" exhaust turbo back LC-1 o2 sensor Hallman manual boost controller EDIS 6 ignition batch fire 60mm throttle body 5 spd T5 borg warner 3.54 lsd
Jim_Blackwood
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Re: After-start idle control (cold)

Post by Jim_Blackwood »

Yes I think you are right. I cranked up the enrichments in an effort to get good starting behavior and there's little doubt I overdid it.
But, I've been getting erratic readings from my LC-1, it was hanging at 7.5 afr yesterday. So after recalibration, wiring checks, restarts etc I ordered a new gage (MTX-AL) and it should be here in a few days. Bit of sticker shock but I'd been saving my pennies.

I didn't have much guidance on the afr settings so that map is pretty much a guesstimation on my part, as is the VE map. Oddly enough it runs pretty well except for startup behavior and being overly rich, at least at points in the tune including WOT, start and warmup. I'd like to get it leaned out but I'm willing to wait for the new gage to do it since it'll be rather pointless otherwise, but I can begin paring down the enrichments bit by bit. Interesting that uptick at the end of your curve. I suppose that must help?

I really haven't used the afr map to tune with before now and don't really understand how it is used. The map seem arbitrary aside from just a few data points like cruise, idle, and WOT, and even those really are a range rather than a set number. I'm having a little trouble understanding how that is much better than just tuning the VE map while driving and watching the afr gage (With a co-driver of course. Well, I guess it does let you eliminate the co-driver). So, learning new things. That's always fun.

Jim

Do you know of a really good thread on tuning using the AFR map and the autotune feature?
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Re: After-start idle control (cold)

Post by Jim_Blackwood »

David, I loaded your curve and it works at least as well as what I had before, maybe a bit better and it is leaner so that's an improvement. What are you using for taper?

Jim
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Re: After-start idle control (cold)

Post by turbo conversion »

I am using an older firmware and it does not have ignore mat function on hot start.

This is what works for me to get around heat soak in the summer.

In the winter that part of the curve is not used as the coolant temperature doesn't get that high while sitting.

The afr table is what your target is for afr and the ve table is what makes it happen.

Once you achieve afr target by tuning ve you can then change afr with the afr table and leave ve alone.

This is possible because of include afr target in the settings, don't include afr requires you to tune the ve table.

David
1976 Datsun 280Z L28ET Garrett GT35R T3-T04E stage3 50 trim 63 A/R housing custom grind cam 2000-6000 rpm 440cc injectors intercooled 18 lbs. boost
3" exhaust turbo back LC-1 o2 sensor Hallman manual boost controller EDIS 6 ignition batch fire 60mm throttle body 5 spd T5 borg warner 3.54 lsd
Jim_Blackwood
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Re: After-start idle control (cold)

Post by Jim_Blackwood »

So then I guess you are basically just guessing about either the best AFR or else the best VE values. I've always just skipped the middle man and edited the VE map directly based on what the WB and the engine was doing. I never saw the effort of dreaming up hopefully ballpark values for the afr as being an advantage. I've done that now anyway, but I'm seeing that you have to exclude areas like idle from autotune and I wonder where the payoff is?

Well, back to work. My MAT sensor came in so I should hook that up.

Jim
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Re: After-start idle control (cold)

Post by Jim_Blackwood »

alrighty that's done. There wasn't a definition for the AEM but it was close to the GM so I just kept the GM resistor value and tweaked the calibration values to match the AEM chart. (It listed 2 resistor values, one was the same as the GM) Seems to work, I was showing 102 ECT and 103 MAT. Hopefully more parts will be in tomorrow.

Jim
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Re: After-start idle control (cold)

Post by Jim_Blackwood »

I found advice on cranking speed and changed that, it seems to start OK at 250 and then does not die which is helpful. Maybe I can even lower the idle speed, but I've got an oscillation I have to get rid of first.

Looking at the latest datalogs (ran a bunch of them today), I have completely turned off the prime pulse and ASE and the car still starts fine. However I have picked up that oscillation.

Also, despite the fact that I have just recently replaced the TPS I'm seeing a lot of spikes on that line. I don't know if that's normal, but when I ran a datalog with it unplugged they went away. (also attached)

Any advice?

Jim
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Re: After-start idle control (cold)

Post by Jim_Blackwood »

Here's another. The pw is 11.4 steady but the engine speed drops from 3400 to 296 then it dies. Still trying to figure out why. Cranking speed was at 250, lowering it to 200 since actual is 135.

Jim
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Re: After-start idle control (cold)

Post by Jim_Blackwood »

Maybe you guys are tired of me but this time I really think I found something.

My injector pulsewidth lags the MAP by half a second. Now why would that be?

Jim

It does it with no enrichments, no accel, no TPS, no IAC.
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Re: After-start idle control (cold)

Post by turbo conversion »

Can you post the msq that goes with your last posted data log?

David
1976 Datsun 280Z L28ET Garrett GT35R T3-T04E stage3 50 trim 63 A/R housing custom grind cam 2000-6000 rpm 440cc injectors intercooled 18 lbs. boost
3" exhaust turbo back LC-1 o2 sensor Hallman manual boost controller EDIS 6 ignition batch fire 60mm throttle body 5 spd T5 borg warner 3.54 lsd
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Re: After-start idle control (cold)

Post by Jim_Blackwood »

This should be it.

Jim
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