Ms tuning assistance

[gslender]

If they are low impedance, you've probably damaged them.

Low impedance injectors require peak and hold circuits to correctly drive them. Not many ECUs support using low impedance due to the fact that you can buy big size high impedance injectors with the same characteristics.

Find out for sure what injectors you have, and maybe consider swapping back the stock injectors for now, until you can start and run the engine normally. Then swap in the big bad ass injectors with a tune that simply requires changing the ReqFuel to suit the injectors sizes.

G

[gslender]

I just checked the tune file again - it didn't have sequential injection enabled.

Under Advanced tab, Sequential Injection -> change from Untimed to Sequential/Semi-Sequential.

I'd also be concerned about those injectors, as again, if they really are 850cc then they'd flow almost 4 times as much fuel as a standard 240cc injector and require very, very small PW to fire. At a ReqFuel of 12ms it would be dumping heaps and heaps of fuel with the VE at 100%.

Something is wrong with them if you can get it to idle with a VE near 50% and the ReqFuel at 12.

G

[elitee]

Any chance you are able to make changes to the msq I need and then I'll try load it on and see how I go

These are the injectors i purchased :

http://www.fiveomotorsport.com/product-search/?v=9790

"Fuel Injector: Custom Fiveo 026IMP850X "

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[elitee]

going by this thread : http://forum.miata.net/vb/showthread.php?t=430494

Looks like my dead times need to be changed that could possible be my issue when the car isn't starting up with the req_fuel set to 3.6.

How would i go about changing the dead times in TS ?

[gslender]

Email sent with changed MSQ attached.

Log the starting and don't make any changes to the tune and send back the log when you can.

G

[bear2230]

Great work gslender. Its people like you and Dann who are willing to help out when someone is in trouble that make this forum a very unique place.

Richard.

[sailaholic]

Oh, and it should be set to 2 squirts for fully sequential injection.

Why would it fire the injector twice per cycle if its fully sequential injection?

[gslender]

Why would it fire the injector twice per cycle if its fully sequential injection?

Err... its not.

I guess you need to really understand MS2 fairly well to fully understand what is going on here.... I'll try and explain.

1) MS2 and earlier never originally had 4 cyl full sequential code. And all the original settings and values were organised and setup for 2 injector control whether you had a 1 cylinder 2 stroke or an 8 cylinder 4 stroke engine that used 2 injectors (probably in the throttle body, or per side). For our MX5 NA6s this meant the original MS2 could control the injectors just like the stock computer in batch configuration. So the settings favoured a world where there was only ever going to be 2 injector drivers.

2) When the Full Sequential mod was added later, this increased the number of injectors to 4, and made the code capable of firing 4 injectors. This new Seq code is independent of the original TunerStudio settings and really only looks at the number of cylinders and 4/2 strokes to work out what to do with the 4 injectors. The new Seq code ignores the squirts/simultaneous or squirts/alternating values - they aren't used in this new code, and if you have it set to 4 cylinder/4 stroke then the fuel will be divided by 4 and equally distributed by the 4 injector drivers at the appropriate engine cycle (ie once every 720 deg).

3) The ReqFuel is a value setting that is used in the PW fuel calculations - its used to baseline the fuel used in cranking and as a base value for when VE is at 100%. The squirts/simultaneous or squirts/alternating values then divide the ReqFuel when TunerStudio writes this data to the ECUs configuration. So if you have these values wrong, then the only thing that gets mucked up, is the fuel calcs and you either need to add more/less when cranking or in the VE cells. It has no other effect than that when using the Full Sequential code.

So, whilst it makes no specific difference to the number actual squirts, getting the values wrong (ie not using either 1 sq/sim or 2 sq/alt) just means you muck up the ReqFuel and need to compensate with odd values in the cranking % and VE tables.

Does that help explain it?

[sailaholic]

Sorry for the slow reply, yah it does help explain it.

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