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Megasquirt MS3 start issue

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hi guys, here it is my first question.

I have a MS3 installed on a honda s2000. I am managing to improve the start of the car, everything else is more or less ok ( some hard work with tps AE).

First, I will tell you what I see as I dont want a direct answer ( do this and this ) as I want to learn and understand.

I think that my Crancking rpm should be like 500rpm? As I see on the log 65524s it is there were the car wants to start?

As I see before the car arrives to 500 the AFR is very very rich, is this due to too much priming pulse?

Just when it fires it suddenly become pig lean and then very rich untill it stabilize. I think that probably this is due to a very low cranking Pulse? is this why first is lean and then suddenly ASE and WUE kick in and I get rich.

Can somebody explain a correct way to start one by one doing a correct starting mod?

I didnt tell before but sometimes I get kickback, is the Ignition correctly set on start?

kind regards

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I tend to set the Cranking rpm as low as possible, 200rpm I believe is the lowest. In case of a weak battery and the starter can't turn the engine over fast enough to tell the MS that it's trying to start.

I'd try playing with the priming pulse and lessen it, then see what the datalog says. I ran mine at zero and just let the cranking pulse with handle the fuel needs during cranking. I haven't had a problem with the fuel during cold starts to adjust the priming pulse.

I usually start very low on the cranking pulse and richen it up til the engine starts.

If there is an order to set them up correctly, I'd work backwards, start with a solid idle at operating temp.

afterwards, possibly the following day, set ASE as low as possible, 5% I believe is the lowest.

Work on the WUE. Then afterwards, let the engine cool down again, double check your WUE as the engine warms up.

Now work on your ASE, not just in the colder(WUE) temps but also in the hotter temps as well.

My car would hunt if I had gone for a drive, went to a store, started the car back up and let it idle, IATs and ECTs were high and adjusting the ASE stopped the hunting

ok understood. So I guess my ignition map for starting is ok right? I was going to put more ignition but I will follow what you say. Priming pulse to 0 and play with cranking pulse at first. Car idles very well what I only see is that it egocor keeps pulling fuel off so I guess my ASE is too high, I will decrease it ones car starts ok I guess.

I will test tomorrow and log the car, by the way this is my ignition map ( see pic )

thx

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Hi Drews2k , did you check ignition offset with timing light before trying to start up , also does the software have runtime values so you can see whats happening with all the start up and warm up enrichments.

Cheers Keith

Yes is checked. I guess the info you ask for. Can be seen on my first post attachment?

Megalogviewer do very good logs I think I will do screenshots tonight

Your EGOCorrection isnt active during cold start is it? Should be set so that it doesnt function until like 70c

13bjunkie you are right. Is not active

"there is an order to set them up correctly, I'd work backwards, start with a solid idle at operating temp.afterwards, possibly the following day, set ASE as low as possible, 5% I believe is the lowest.Work on the WUE. Then afterwards, let the engine cool down again, double check your WUE as the engine warms up. Now work on your ASE, not just in the colder(WUE) temps but also in the hotter temps as well."

Yes, this is the right idea: work backwards. Often it is the switch between after start and warm up enrichment that causes problems.

thank you for your advice.

Here is what I did ( look attach )

I have set to 0 the priming and work on the Cranking pulse.

ASE HAS something to see exactly when the car goes to idle just after starting right? when it idles the WUE comes? I modified a bit the Wue and set the EGOcor NOT TO kick it until 60Cº.

I started and stopped car several times and only had 1 kick back that I think was because starter was getting hot or so hahaha

I see that the start now is ver contundent and fast but... is it too much Cranking pulse? or is it ok? I mean this because probably there is too much fuel wasted ruining my oil or is it a normal value? at 80cº if I decreased to 110 cranking pulse car doesnt start same way.

What do you think. thanks for your inputs and help.

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Cranking enrichment is in operation until the engine exceeds the rpm set in the startup rpm box. So, if its set to 300, anything over 300 will move into After Start Enrichment. Afterstart enrichment has a decay time that is specified either in engine cycles or time, after ASE decays, it will move into Warmup Enrichment and read from that table until your WUE gets to 0% at operating temp

Understood 13bjunkie. I think startup is set to 300rpm. In this case I see the engine start moving at 220rpm or so then goes up so I think is ok. I didn't know the exact procedure now yes, thank you I will start playing with ASE, I did ones and car started supercars style reving to 3500 rpm :D but when is cold it cant be good ;)

I will try to start and log and check again when is cold and tell you the results.

Thank you very much

well today I went ( no laptop ) to start the car and it started but I think it need a bit more of cranking pulse at near didnt start but finally did at first shoot.

I guess that if a car start correctly revs to 1500 rpm and then goes down to 600rpm near stop but suddenly go up and stay at 980rpm, I need more ASE right?

You may have enough fuel but not enough air.

I dont know what happened here... later it started ok.

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