Inconsistant restarts. Tuning issues. MS2 V3 2.888

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durson1
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Inconsistant restarts. Tuning issues. MS2 V3 2.888

Post by durson1 »

I recently got my car running. Some non MS setbacks slowed me down, but I am back to tuning and day to day the car will start or it won't. Yesterday it started right up and idled ok. Today it started then died 3 times. Then cranked and cranked with no start. When I did get it started I had to keep the throttle open to keep it running. When I check my timing at idle the timing marks aren't consistant. With my timing gun on, the mark jumps around. Not steady at 11 degrees, where I have it set at idle.
To keep it simple I used 2 point instead of table for WUE, ASE etc. I just took a long datalog, which is apparently too big to upload, Its 3.3mb, 2mb is the limit, mostly at idle trying to get things dialed in to get a little more consistancy. I ran it thru the VE analysis in MLV and weighting was 528 or so.
MLV says the higher the weighting the more sure you can be that its correct. Is that high? I dono what is. Watching the log means nothing to me. I'd really like to get an opinion on it and my msq to get me going in the right direction. Seems like I've been tuning in circles.
After much tuning things are almost back where I started, comparing old msq's. Frusterating.
Car is a VW rabbit. 2.0L 8v, I can give more spec's f needed.
Thanks for any responses.
I attached my msq. I don't know what to do about the log file. I guess I could email it if someone is willing. I'll take a shorter log tomorrow and attach it. Also that will give me a chance to load the VE table generated by MLV.

I guess I'll take a shorter log tomorrow.
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durson1
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Re: Inconsistant restarts. Tuning issues. MS2 V3 2.888

Post by durson1 »

My TPS values are closed= 184 open=909. Is that right. I figured out which connection was which following the directions in the megamanual. My values were different but still increased as I opened throttle if I switched the 5vref and the signal. But the values were more like 104 and 200 something like that. So I wired it this way due to the greater distance between the values. But the manual says blow 155 closed and above 178 open. I'm way off that. That could be a big part of my issue, yes, no? Maybe I should rewire. So during cranking am I in flood clear? That sucks if I am.
durson1
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Re: Inconsistant restarts. Tuning issues. MS2 V3 2.888

Post by durson1 »

I was having internet access issues so first of all thanks.

The TPS thing makes sense since it looks like it goes off TPS %. So as long as it is calibrated it should be ok.

Been doing alot of reading. So from what I've read, if I am understanding, I should set my idle and cruise AFR targets to 14.7 and get my VE table dialed in. With enrichments off. After setting my cranking PW, and cranking PW is Cranking PW alone, not VE dependent. Then Start adjusting my AFR targets to where I want them, rich on accel, lean at cruise, and whatever it idles smoothest at with the lowest map. then bump up enrichments and lower VE to compensate when cold. And warmup period is the sum of VE + ASE +WUE. I think it may be easier to not even use ASE. ASE and WUE seem to overlap some to me. Since ASE is time based and WUE is temperature based enriching by temp seems the more logical way to go, and ASE I don't think I have a use for since it would enrich on top of WUE for given # of ignition cycles.

Cranking ignition advance is the sum of initial + cold cranking advance + the lowest rpm by highest 1 or 2 map bins.(given a highest map row of 100 and lowest rpm row of 500... give or take) Less advance= easier start. Then at idle map by idle rpm bin more advance for more steady fuel efficient idle.
Yes? No?

This is where I will start tomorrow. Any other input from experience would be helpful. Am I on track or am I off on anything.
devastator
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Re: Inconsistant restarts. Tuning issues. MS2 V3 2.888

Post by devastator »

durson1 wrote:ASE and WUE seem to overlap some to me.
They do overlap, but many engines need a little extra fuel for a short amount of time after starting. If your engine dies a few seconds after starting, but runs alright at colder temps ,(once you get it past the immediate stalling), then the WUE is probably pretty close and you need some ASE.
durson1 wrote:Cranking ignition advance is the sum of initial + cold cranking advance + the lowest rpm by highest 1 or 2 map bins.(given a highest map row of 100 and lowest rpm row of 500... give or take) Less advance= easier start. Then at idle map by idle rpm bin more advance for more steady fuel efficient idle.
Yes? No?
You might find it useful to increase the number of skip pulses. This will let the engine crank at the default advance setting of the dizzy, instead of the MS applied value. I have to do this or my idle advance settings, (18 degrees), will stop my starter.
Sandrail-ACVW 2276 cc, Turbo
MS-II W/spark burning E85
The sand must be punished. :twisted:
durson1
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Re: Inconsistant restarts. Tuning issues. MS2 V3 2.888

Post by durson1 »

I guess I never read that far into skip pulses. Mine has been set at 1. What is yours set at? Probably depends on how many cranks to start. I have been moving my advance around the the 500 rpm row at 100, 90, and 80 kPa for starting. But the only times I will see that rpm and kPa is at crank anyway. My advance map I borrowed off someone had 18 in that row and my engine would just stop cranaking like yours. Must have been using the skip pulses with that advance map.

So i may need some ASE. My engine started then died until I got the WUE dialed in. It was still a little rough just after start then it stablized.

I got it up and running today pretty decent. My idle advance is at 20, rpm at about 1000-1100 depending on if radiator fan is running or not, and a map of 32. It idles smoother than it ever has.

Could someone give me A good time to use injection timing delay? I understand what it is, but is it something worth playing with? Or when should you start making changes there? What syptoms will this fix?
durson1
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Re: Inconsistant restarts. Tuning issues. MS2 V3 2.888

Post by durson1 »

In regards to the rpm drop when the radiator fan runs. Should I be able to correct that in the voltage correction? In the "Battery voltage correction" under injector characteristics? Mine is set to .2 ms/v currently. If I up that can that correct my rpm drop. I'm not using the stepper motor but I don't think a stepper mtor can be used as an idle stabilizer anyway from what I've read. Or can I set a spare output to open an air bypass solenoid when the fan kicks on?

Also my injectios per cycle is set at 2 simultaneous. If I go to 2 alternating it stalls out. I have heard to confirm you have the right injector opening time increase or decrease your injections per cycle and raise or lower if lean or rich. What about going from simultaneous to alternating? I would think I would be able to run either if my required fuel is calculated correctly. Or is this not the case. I wired injectors 1 &4 to inj. bank 1, and 2&3 to bank 2. So I should be able to use alternating.
devastator
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Posts: 333
Joined: Mon Feb 11, 2008 10:19 am
Location: Kinda near Tucson Arizona

Re: Inconsistant restarts. Tuning issues. MS2 V3 2.888

Post by devastator »

durson1 wrote:I guess I never read that far into skip pulses. Mine has been set at 1. What is yours set at?
15, I think. Increase yours and see if it helps. You can always put it back if you want.
durson1 wrote:But the only times I will see that rpm and kPa is at crank anyway.
Watch your logs as you may hit them on decel. Remember also that MS will "look" at the cells next to the one it is in and interpolate between them for it's applied value.
durson1 wrote:So i may need some ASE.
Try it. If you don't like it, put it back.
durson1 wrote:Could someone give me A good time to use injection timing delay? I understand what it is, but is it something worth playing with? Or when should you start making changes there? What syptoms will this fix?
This will only affect your idle. Move it up in increments of 10. Once you find the best idle, lock this number in, (even if it is zero).
durson1 wrote:In regards to the rpm drop when the radiator fan runs. Should I be able to correct that in the voltage correction? In the "Battery voltage correction" under injector characteristics? Mine is set to .2 ms/v currently.
If your fan is electric, the draw on the alternator is pulling down your engine so changing the voltage settings in MS will not affect anything, unless, of course, the alternator is not putting out enough power in the first place. Try adjusting the VE bin that the idle drops to to compensate instead.
durson1 wrote:Or can I set a spare output to open an air bypass solenoid when the fan kicks on?
You should be able to do this.
durson1 wrote:I have heard to confirm you have the right injector opening time increase or decrease your injections per cycle and raise or lower if lean or rich.
I've never heard of that.
durson1 wrote:What about going from simultaneous to alternating? I would think I would be able to run either if my required fuel is calculated correctly.
You can switch, but it usually requires a tuning of the VE table. Although my engine was wired and set-up for simultaneous, I run much better set at simultaneous.
Sandrail-ACVW 2276 cc, Turbo
MS-II W/spark burning E85
The sand must be punished. :twisted:
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