Hot Start, Starts then Dies

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Re: Hot Start, Starts then Dies

Postby rukavina » Thu Nov 02, 2017 10:39 pm

This is how I did mine originally
Do anything to get it to temp
At temp get it idling good. Fuel and timing. At this point shut it down and let it cool overnight.
Now you have one shot to tweak ase start engine and see if it stays running until wue
Tune wue to keep it running.
Now you can't do anything with these settings til next morning.
Step and repeat til happy
4wheel drive 454 vortec on ms2 w/gpio for 4l80e Trans control
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Re: Hot Start, Starts then Dies

Postby Blown88GT » Fri Nov 03, 2017 12:50 pm

enigmaticdream wrote:...I had two more questions
1. Should the x/y axes values/scales of the VE Fuel, AFR, and Ignition Timing tables be the same?
2. Is there any reason to go back to closed-loop?..

1. To me, it makes sense to do that, but I don't think it's necessary.
2. Only if it makes the idle more stable. Closed-Loop adjusts the valve position to achieve a target RPM.
1988 Mustang GT, 57k miles, Orig. Owner
ProCharger 600B I/C, 12psi, FRPP Hdrs, Flwmstr F2, 3G Alt, Mk8 Fan & DCC, 3.55's, Prog Sprng, Subfrms, UCA, LCA, FCA, Tokico 5-way, CSA 16x8, Bridgestone RE760 225/50R16, Crane HI-6, Kirban FPR, MS2, DIYPNPF60, LC2, C&L76mm blo-thru MAF, 30lb FRPP
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Re: Hot Start, Starts then Dies

Postby enigmaticdream » Sun Nov 05, 2017 10:48 am

Okay, so I took a day off from tuning and mulled over some stuff. My last tune I had cold start and cold idle doing really well, but once I got into hot idle it would start to oscillate after blipping the throttle. Looking around TunerStudio I found a few more settings to turn off. The three I disabled were EGO, Idle Advance, and Accel Enrichment. Since it was driving me up the wall that the car idled so well when cold but not when warm I decided to continue to disable any settings that might be manipulating of VE/Timing/AFR settings. Analyzing the logs neither EGO or Idle Advance seemed to be doing anything but I disabled them regardless. Finally I got thinking about how well the car idle when cold but not when hot and the two main factors that seems to be driving this was the AFR values were richer and the icv duty cycle was higher (higher RPM). So I decided to apply that to my tune, I knocked the target AFR at idle from 14.7 to 14.5 and changed the icv duty cycle from ~32% to 36.6%.

The results of my changes was that the car now seems to be cold start and idling great and hot start and idling great. :yeah!: I felt so good about it that I decided to do a little bit of VE auto tuning by driving around. The car felt great with minimum throttle input, on the highway, coming to stops, etc. As you would expect from a car.

So getting home I decided to do some heat soak restart testing. I turned the car off for 10 minutes with a blanket over my lidless engine bay to try and heat soak the IAT. I did this three times with tweaks here and there to try and fix the problem. So the log and tune attached are my last attempts to fix or help counter a heat soaked IAT. Are there any settings I should look into for handling this? The car will fire up (sometimes die), stumble and oscillate a bit until what I can only gather is the IAT sensor cooling off enough to function correctly. Once it is pass this the car returns to normal.

Things to note about the tune
-At the moment WUE has its last value at 161 instead of 180 like I originally had because I noticed it would drop back into WUE while I was driving around this morning. It was about 55F out so the cooler temp dropped the CLT sensor down below 180. I'm going to rescale this table but I just quickly turned it off while I was driving around because I had auto tune on and I didn't want it messing up my VE values.
-I tried spiking ASE Taper at 180 above to run longer to try and counter act the leaning out/oscillation I'm getting with the heat soak.
-I have not matched my AFR, VE, and Ignition tables X/Y axes.
-I have not removed the 300/400rpm column from the AFR, VE, Ignition tables yet. I kept them but default them to be identical to my expected idle VE cells. I'll remove these completely later this week after I get enough cold and hot idle/starts under my belt and feel comfortable.

Things about the log
-After the car restarts I try giving it some throttle input to counter or prevent it from dying.

Anyway, any feedback would be great and thanks again for all the help I've received.
Attachments
1986_Porsche_911_Supercharged_2017-11-05_12.33.06.msq
(250.1 KiB) Downloaded 6 times
2017-11-05_12.07.58_log.zip
Contains a log of the heat soak idle oscillation
(155.5 KiB) Downloaded 3 times
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Re: Hot Start, Starts then Dies

Postby Blown88GT » Sun Nov 05, 2017 1:45 pm

I had the same problems, idled perfectly when cold but oscillating when hot.
You just have to keep trying different settings, like you're doing.
I was told it was probably heat-soak, but it's not. I even temporarily moved the IAT sensor in front of the radiator, made no difference.
I went to closed-loop because it attempts to lock onto an rpm, i.e. your idle rpm
See Closed-Loop Idle Target RPM's.
I think you're ready to try closed-loop.
The issues you state are exactly what it's used to correct.
Your engine is nothing like mine but it's interesting you are having the same issues.
Mine always fires up, cold or hot, never dies unless am at full steering lock backing up & I don't give it enough throttle. It always did that with the OEM ECU & just had to live with it.
It still oscillates a little bit under certain conditions which seem to vary. I attribute it to the centrifugal blower which never bypasses 100% at idle, BOV is not big enough.

You're making a lot faster progress than I did.

BTW, I made an MS3 Project just to see what the differences are. Also, allows me to do a TS compare tune with another MS3.

There still some setting that look wrong & they will affect your idle quality.
Injector Dead Time & Battery Correction Voltage are not those calculated for your LU-60's
DT = 0.526 (you have 0.400)
BCV = 0.112 (you can enter all the values to get the curve)

All injectors are the same, but there is a bug in MS3 code, so you have to enable all 6, even though they are identical.
viewtopic.php?f=131&t=66098

Your crank to run taper time seems pretty short (1 sec),
What happened to your ASE & ASE Taper?
1988 Mustang GT, 57k miles, Orig. Owner
ProCharger 600B I/C, 12psi, FRPP Hdrs, Flwmstr F2, 3G Alt, Mk8 Fan & DCC, 3.55's, Prog Sprng, Subfrms, UCA, LCA, FCA, Tokico 5-way, CSA 16x8, Bridgestone RE760 225/50R16, Crane HI-6, Kirban FPR, MS2, DIYPNPF60, LC2, C&L76mm blo-thru MAF, 30lb FRPP
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Re: Hot Start, Starts then Dies

Postby enigmaticdream » Mon Nov 06, 2017 7:46 pm

Blown88GT wrote:I had the same problems, idled perfectly when cold but oscillating when hot.
You just have to keep trying different settings, like you're doing.
I was told it was probably heat-soak, but it's not. I even temporarily moved the IAT sensor in front of the radiator, made no difference.
I went to closed-loop because it attempts to lock onto an rpm, i.e. your idle rpm
See Closed-Loop Idle Target RPM's.
I think you're ready to try closed-loop.
The issues you state are exactly what it's used to correct.
Your engine is nothing like mine but it's interesting you are having the same issues.
Mine always fires up, cold or hot, never dies unless am at full steering lock backing up & I don't give it enough throttle. It always did that with the OEM ECU & just had to live with it.
It still oscillates a little bit under certain conditions which seem to vary. I attribute it to the centrifugal blower which never bypasses 100% at idle, BOV is not big enough.

You're making a lot faster progress than I did.

BTW, I made an MS3 Project just to see what the differences are. Also, allows me to do a TS compare tune with another MS3.

There still some setting that look wrong & they will affect your idle quality.
Injector Dead Time & Battery Correction Voltage are not those calculated for your LU-60's
DT = 0.526 (you have 0.400)
BCV = 0.112 (you can enter all the values to get the curve)

All injectors are the same, but there is a bug in MS3 code, so you have to enable all 6, even though they are identical.
viewtopic.php?f=131&t=66098

Your crank to run taper time seems pretty short (1 sec),
What happened to your ASE & ASE Taper?


I've only been making good progress with good help :)

Here are my responses to your questions/comments
-I used the spreadsheet you referred me to earlier to calculate the dead time with the LU60 profile. Here is a link to my copy of the spreadsheet with the values from the injectors. https://docs.google.com/spreadsheets/d/ ... sp=sharing. I'm using the value in cell N21 for my dead time. I also created the "Injector Dead Time Curve" with cells M24:N29. How did you get the value of .526 for dead time? What am I doing wrong?
-Regarding the bug with all injectors are the same. Are you saying I need to update the "Injector Dead-Time/PWM" settings to have "Inj Parameters" set to "Individual" instead of "Same"? Please see the attached picture.
-I'm not following you on the Battery Correction Voltage. Where is that option? I tried searching but the closest thing I came up with was Dwell Battery Correction, but those values seem a lot different than the one you provided.
-Crank-To-Run taper was done by the previous owner. I have it currently disabled with open loop. With it disabled I shouldn't be using it right? Do you have a suggest on a value?
-Regarding ASE/ASE Taper, it is still there. Does it looks weird or something?

I did some more reading/thinking over night. I got an idea of how to handle heat soak iat issues and looking around online it seems like others have used this method. Below are the three steps I took.
1. I updated ASE and ASE Taper to have an increase in fuel delivery if CLT goes above 185F. I also increased the ASE Taper until I found a value I liked to allow it to run richer until the IAT temp stops heat soaking a bit.
2. Add/work on the MAT Air Density Table. From what I gathered it is the equivalent to the MAP Correction Table. So what I did was add extra fuel when MAT is above 130F. The idea being that during hot restart with heat soak it will provide extra fuel until the temperature is back to normal. I need to do some more test with this in a situation like sitting idle for a really long time and not a hot start with heat soak.
3. Enable "Ignore MAT Correction During ASE"

The results of my changes was I almost eliminated leaning out during hot starts with heat soak. What I did was turn the car off and throw a moving blanket over the engine bay to simulate a hot summer/force heat soak the IAT. I let it sit for about 10 minutes then fired the car up and see how it ran. I tweaked the ASE and MAT settings above and repeated. I let the car cool off for about an hour and tried firing it up and it fired up real quick and was relatively warm.

Attached is my current tune and a hot heat soak log for observation. I'm not 100% sure I should be doing it this way, but hey it works. I haven't started closed idle work yet because I want to read a bit more about it before I start attacking it. I can definitely confirm it needs work though because I tried enabling it briefly today and the idle was oscillating. If I disabled it and went back to open loop the idle was solid. I also departed from keeping ASE and WUE using the same temp. Part of this is due to hot start with heat soak and the other is that the engine is warm before 180F. I need to ultimately rewire and move the CLT to use cylinder heat temperature but for now this will get me out of WUE and into regular functionality.

Thanks
Attachments
1986_Porsche_911_Supercharged_2017-11-06_18.09.56.msq
(250.07 KiB) Downloaded 6 times
2017-11-06_18.06.28_log.zip
contains hot start with heat soak
(110.26 KiB) Downloaded 3 times
injector.PNG
Pic of injector setup
injector.PNG (70.38 KiB) Viewed 192 times
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Re: Hot Start, Starts then Dies

Postby Blown88GT » Tue Nov 07, 2017 7:31 am

enigmaticdream wrote:...
-I used the spreadsheet you referred me to earlier to calculate the dead time with the LU60 profile. Here is a link to my copy of the spreadsheet with the values from the injectors. https://docs.google.com/spreadsheets/d/ ... sp=sharing. I'm using the value in cell N21 for my dead time. I also created the "Injector Dead Time Curve" with cells M24:N29. How did you get the value of .526 for dead time? What am I doing wrong?
-Regarding the bug with all injectors are the same. Are you saying I need to update the "Injector Dead-Time/PWM" settings to have "Inj Parameters" set to "Individual" instead of "Same"? Please see the attached picture.
-I'm not following you on the Battery Correction Voltage. Where is that option? I tried searching but the closest thing I came up with was Dwell Battery Correction, but those values seem a lot different than the one you provided...

-Crank-To-Run taper was done by the previous owner. I have it currently disabled with open loop.
With it disabled I shouldn't be using it right? Do you have a suggest on a value?-Regarding ASE/ASE Taper, it is still there. Does it looks weird or something?
...

I'll comment on the spreadsheet now & the rest later. Anything new will be added to this post.
BTW, Quoting everything makes this thread too long.
MS3 is still a work in progress.
He says in note at top: "** Small Pulsewidth Curve is BETA and is probably total garbage! **
He recently upgraded his hardware from MS2 to MS3, so the conversion uses the values from MS2.
Use the MS2 number for DT
BCV values are probably OK.
I used a fuel pressure of 40 psi instead of 39.15. Enter the fuel pressure you are using. Unlikely it's 39.15.

I think the pic is OK, except Inj F is still using Curve 1; A-E are using Curve 2.
1988 Mustang GT, 57k miles, Orig. Owner
ProCharger 600B I/C, 12psi, FRPP Hdrs, Flwmstr F2, 3G Alt, Mk8 Fan & DCC, 3.55's, Prog Sprng, Subfrms, UCA, LCA, FCA, Tokico 5-way, CSA 16x8, Bridgestone RE760 225/50R16, Crane HI-6, Kirban FPR, MS2, DIYPNPF60, LC2, C&L76mm blo-thru MAF, 30lb FRPP
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Re: Hot Start, Starts then Dies

Postby enigmaticdream » Tue Nov 07, 2017 7:48 am

Ah okay that makes sense regarding the spreadsheet. So I updated the spreadsheet to use 43.5psi (based on what was in the tune for static fuel pressure. I'll double check that value tonight with the fuel pressure gauge on the engine to make sure they match. I also updated the tune to use the MS2 dead time (0.515) instead of MS3 dead time (0.423). Lastly, I fixed the Inj F not pointing to the right curve. Nice find! Those are all the changes around the spreadsheet updates.

This morning I also dropped the 400rpm column off of Fuel AE, AFR, and Timing tables. With open loop idle I was really never hitting the 400 rpm area. With the loss of the 400rpm column though I added a new 1200rpm column after shifting things around a bit. I particularly want a 1200 rpm column so I can have more control on fuel and ignition timing when I'm cold starting. My target cold idle for CL when I get there will start at 1200rpm and taper down to 950rpm when the car is warm. I read a good blog post on tuning close idle last night. It was a good refresher on what all the different settings do. If I feel comfortable with all these changes I made allow the car to still run well when I run it tonight I'll probably start working on closed-loop idle.

Thanks
Attachments
1986_Porsche_911_Supercharged_2017-11-07_09.46.47.msq
revamped dead time and dropped 400rpm column
(238.62 KiB) Downloaded 7 times
Supercharged Porsche 911 on MS3Pro, Sequential Injection, Vortech V1 SC
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Re: Hot Start, Starts then Dies

Postby Blown88GT » Tue Nov 07, 2017 1:53 pm

Since you responded, I'll continue here.

The default value for DT was 0.9, BCV default was 0.2, the calculated values are lot closer.
That big a difference throws the tune way off, but now you're tuning after the corrections, so OK.

Why do you have 2 Ignition Tables? Maybe because you have dual wheels?
General Settings says Secondary Ignition Load is disabled.
The tables are a little bit different.
Can't tell you what to do, you'll have to figure it out.

Good that you dropped the 400rpm column. It was providing no benefit.

You can also control idle with Idle Advance. Right now, it is turned off.
Just noticed Idle VE. It's also turned off.
MS3 has more control than MS2 & a lot more settings.
1988 Mustang GT, 57k miles, Orig. Owner
ProCharger 600B I/C, 12psi, FRPP Hdrs, Flwmstr F2, 3G Alt, Mk8 Fan & DCC, 3.55's, Prog Sprng, Subfrms, UCA, LCA, FCA, Tokico 5-way, CSA 16x8, Bridgestone RE760 225/50R16, Crane HI-6, Kirban FPR, MS2, DIYPNPF60, LC2, C&L76mm blo-thru MAF, 30lb FRPP
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Re: Hot Start, Starts then Dies

Postby enigmaticdream » Thu Nov 09, 2017 1:28 pm

The 2 ignition tables was from the previous owner. I think it blends timing when in boost or something.

Anyway, I'm postponing anymore tuning for the moment. I've decided to revamp the CLT sensor from using oil vapor temp to cylinder head temp. It should provide a more stable coolant temp (not fluxuating a ton with air movement. I was getting a lot of temp changes with movement), provide quicker warmup, and it is the temperature the stock ECU used for determining WUE and determining when the engine was warm. I just think it will be a waste of time for me to continue to work on the tune just to have to go back and redo it again. Luckily the wiring should be easy since they're relatively close to each other.

I'll post back once I've done this and revamped the WUE for whatever the new "warmup" temp becomes.

Thanks for all the help so far!

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Re: Hot Start, Starts then Dies

Postby enigmaticdream » Thu Nov 30, 2017 6:56 pm

Alright, I finally finished rewiring the CLT sensor to use cylinder head temperature instead of oil ventilation temperature. I had a new tune that I had been messing with but loading it on the car causes all kinds of problems. Thankfully my most recent tune was on the forums, so I reverted it back to that and the car fired right up. I tweaked the fuel pressure after some more research while working on the car. The car's FPR is a 2.5 BAR setup which is around 36.3psi, not 43.5 like the PO had it *sigh*. So with that tweak and updating the injector dead time to match I had to tweak the VE table a bit. Since the car was already warmed up by the time I switched back to the old tune I decided to just worry about getting AFRs back in range. I drove around a bit with auto-tuned running to get cruising AFRs in range and the car ran as expected. The idle is oscillating again, but I think I just need to utilize the same methods of tuning I used last time to fix it. I'll worry about new ASE and WUE next time I can cold start it.

I've got to work on figuring out what's considered warmed up and the high for the new CLT temp range. I couldn't find much info in terms of CHT max temp (when operating okay) anywhere online but I noticed it was around 300-310F idling outside the garage. I followed the diyautotune procedure for getting the temp/ohms matching pairs for MS and put them in. Anyway, no tune or log file this time. Just an update that I'm back and working on the car again.
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