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Megasquirt Wasted spark setup
Posted: Sat Apr 11, 2015 8:45 pm
by JakeusSnakeus
Hi all me again
Finally got the MS built and in the car. Got a few questions but first pictures, we all like pictures:
Mainboard
55pin Breakout board
Crimped and heat shrink'd the cable for the IAT
Re-used the connector from the AFM as I'm trying to keep the factory harness as stock as possible
High quality Chinese air filter
E36 TPS - bit of a bodge but its in tight
Soooo.... TPS, CLT, IAT are all calibrated.
I cant find where to set the following settings from the wiki in Tunerstudio (V2.6.14) can anyone point me in the right direction:
Squirts Per Engine Cycle = highest value so that idle pulse width is no less than 2.0 ms, if possible, and your Req_Fuel is less than 15-18 milliseconds, but more than 6 milliseconds
Injector Staging = Alternating
Engine Type = Even Fire
Tach Input/Ignition Options
Number Of Coils = Wasted Spark (or single coil if single coil)
Spark A output Pin = D14 (again can be sparkA if using the stock transistor).
Trigger Wheel Settings
Tooth #1 angle = 84 Wheel Speed = Crank Wheel
Re: Megasquirt Wasted spark setup
Posted: Sat Apr 11, 2015 9:16 pm
by Lurch320i
Where did you get that pipe for the IAT sensor?im after one to get my Ms sorted
Also just commenting to subscribe to this is as I'm sure I'll need some of the advice you'll get in this
Re: Megasquirt Wasted spark setup
Posted: Sat Apr 11, 2015 9:22 pm
by JakeusSnakeus
Ebay I'll PM you a link. Be warned it is the definition of cheap and nasty but it does the job for the time being.. You might be better off getting an air filter and some tubing and just drilling a hole.
Re: Megasquirt Wasted spark setup
Posted: Sat Apr 11, 2015 9:35 pm
by gromgsxr
megasuirt 2 on a v3 main board with a diy bob, what firmware version?? 2 squirts per cycle alternating works well if using 2 injector driver ( batch fire ) up until tach/ignition options should be in the 'basic/load settings' under "engine and sequential settings"
the ignition bits should be 'ignition settings' then "ignition options / wheel decoder" thats assuming your using a fairly resent ms2 extra f/w
what are you doing about the icv i didn't see any mods to run that properly?
Re: Megasquirt Wasted spark setup
Posted: Sat Apr 11, 2015 10:33 pm
by JakeusSnakeus
FW: V2.92
What version of tuner studio are you describing? The menu's aren't anything like that in mine.
For PWM of the ICV ive got a TIP121 in Q4 (yellow wires)
Re: Megasquirt Wasted spark setup
Posted: Sat Apr 11, 2015 10:37 pm
by gromgsxr
its the firmware you ecu has on it that dictates the menu's if you connect your ecu to the computer and power it on it will tell you the fw number at the top of tuner studio. i would assume you are running the 3 wire icv??
by the sounds of it your ecu may have the b&g firmware on there, id change it over to ms2 extra if i were you
Re: Megasquirt Wasted spark setup
Posted: Sat Apr 11, 2015 11:14 pm
by JakeusSnakeus
Ah ok cool... yea its the B&G firmware i didn't know there where alternatives.
Yea the original 3 wire
Re: Megasquirt Wasted spark setup
Posted: Sat Apr 11, 2015 11:47 pm
by gromgsxr
http://www.msextra.com/ you will find firmware and the correct manuals there. i not sure if the b&g f/w supports wasted spark, besides the extra code has more features and better support.
if you just have 1 tip121 you can only drive one side of the icv you can either use a big ass resistor (40 ohm 50w) on the other side to keep it closed then the ecu pull it open or you can build a circuit to drive both sides of the icv
http://www.msextra.com/forums/viewtopic ... 01&t=41760
some info on the second option
Re: Megasquirt Wasted spark setup
Posted: Sun Apr 12, 2015 12:06 am
by JakeusSnakeus
Ok thanks, yea I'm already in the process of uploading the ms extra fw.
How do the 3 wire's hold up when boosted? That's the way I'm planning to go eventually so not sure if i should invest time in getting it to work.
Re: Megasquirt Wasted spark setup
Posted: Sun Apr 12, 2015 12:22 am
by gromgsxr
pass iv not used one with boost but as long as its plumbed in correctly i dont see why you could not use it, many a turbo car used a pwm icv cosworth's for instance and there icv's never totally seal off.
if its an every day driver and you dont want to feather the throttle for the first 50 seconds or so to keep the engine running on a cold day or have to re start the engine a few times or dint mind having it stall out on junctions when cold then you can live with out the icv. but on a day to day car that lot could get tedious
you could alway swap it out for a 2 wire icv then you could drive that without any mods as long as you have the diode in your tip121 mod you have done.
Posted: Tue Apr 14, 2015 8:43 pm
by JakeusSnakeus
Cool ill probably just get round to making the circuit at some point.
Where is this screen in TS? (Output Pin Options)
one of my coils is getting very hot, i think its just on continuously
Re:
Posted: Tue Apr 14, 2015 8:54 pm
by gromgsxr
i recon the bip will be shorted to ground.... you used the 3 led's to drive your coils?
the pick you posted are for ms1 the settings are different.
Re:
Posted: Tue Apr 14, 2015 10:01 pm
by JakeusSnakeus
Yea 3 led's
Re:
Posted: Tue Apr 14, 2015 10:10 pm
by gromgsxr
id be checking for continuity to ground on the offending bip373, its really easy for a small burr to cut through the mica insulation and ground to the back of the transistor. i can look at the msq to see if its to do with the settings but more than likely a h/w issue.
Re:
Posted: Wed Apr 15, 2015 12:01 am
by JakeusSnakeus
thanks man, i've pm'd you a link to the tune, im going to test for grounds now..
Re:
Posted: Tue Apr 21, 2015 5:25 pm
by JakeusSnakeus
It lives

Re:
Posted: Fri Apr 24, 2015 1:05 am
by JakeusSnakeus
Thanks for your tune grom
I didn't copy your spark table as its not the same size as mine so i copied the VE table and used the spark table from
http://wiki.diyefi.co.uk/index.php?titl ... Conversion
something's not right tho... very shakey and unstable. I'm sure its just the timing as its back firing etc
In test mode i checked that each plug was firing as per below:
Spark A = Cylinder 1 & 6
Spark B = Cylinder 5 & 2
Spark C = Cylinder 3 & 4
Re:
Posted: Fri Apr 24, 2015 8:01 pm
by JakeusSnakeus
lol found the import/export button

Re:
Posted: Fri Apr 24, 2015 9:05 pm
by gromgsxr
are all the cylinders firing now? it sounds like you may have a cylinder or 2 down. if you can capture a datalog il have a peek.
Re:
Posted: Sat Apr 25, 2015 11:09 am
by JakeusSnakeus
All cylinders are firing I've tested each one. What kind of kPa do you see at idle?
Ill log some stuff now...
Re:
Posted: Sat Apr 25, 2015 12:55 pm
by gromgsxr
35-38kpa, you want to be rich for idle 13.5-14afr and about 16btdc for timing.
Posted: Sat Apr 25, 2015 1:04 pm
by JakeusSnakeus
Re:
Posted: Sat Apr 25, 2015 1:12 pm
by JakeusSnakeus
I'm getting like 70kPa at idle :S
Re:
Posted: Sat Apr 25, 2015 2:39 pm
by gromgsxr
il have a peek after work
Re:
Posted: Sat Apr 25, 2015 6:32 pm
by gromgsxr
AFR is mia do you not have a lambda sensor? it does look like its running a bit rough. not a lot jumps out at me but you do have a bit of sync loss 3 times it happens in the log can you take a tooth and a composite log so can see whats going on with the rpm signal. and at one stage the spark advance jumps up to 83.9 btdc not sure where that is from so if you can get the current msq up as well
Re:
Posted: Sun Apr 26, 2015 12:03 am
by JakeusSnakeus
Thanks man been out all day so didn't get chance to reply earlier. No lambda yet getting one soon. Its back firing and knocking badly not driveable at all, starts stalling, popping and banging under throttle. RPM Will climb if you feather it very gently.
Here's the latest file:
https://dl.dropboxusercontent.com/u/189 ... 20Tune.zip
How do i go about making a composite log?
Re:
Posted: Sun Apr 26, 2015 12:39 am
by gromgsxr
http://www.msextra.com/doc/pdf/html/Meg ... e-3.3.html pages 182- 186 covers the different type of logs and how to record them.
did you import the 16x16 ignition table in the the 12x12? im not convinced it worked properly, the timing figures in the log seem a bit funny in some places they dont seem to match the table.
and one more thing have you tried with the sequential batch fire off thats one of the few settings i have not had a play with so could be one more thing to rule out the rough running.
Re:
Posted: Sun Apr 26, 2015 2:57 pm
by JakeusSnakeus
I'll get some logs to you either tonight or tomorrow.
yea tuner studio re-scales the table as best it can i guess, i should surely be able to enter some generic values around the tick over area's and at least have it idle smoothly. Ill see if the batch fire setting makes it any better,
Re:
Posted: Sun Apr 26, 2015 3:03 pm
by gromgsxr
what i saw on the log aside from there being a time when the timing jumps up to 84 btdc for no reason. The timing was in a part of the ignition table with 18-19 deg in but the ecu was commanding for 10-11 deg not the 18-19 that was in the table.
Re:
Posted: Sun Apr 26, 2015 3:27 pm
by JakeusSnakeus
how odd....
Re:
Posted: Sun Apr 26, 2015 3:31 pm
by gromgsxr
im womdering if importing the larger table did odd things
Re:
Posted: Tue Apr 28, 2015 11:57 pm
by JakeusSnakeus
Yo! been busy only just got chance to do this...

it wont run now just detonates
https://dl.dropboxusercontent.com/u/189 ... 20logs.zip
Re:
Posted: Wed Apr 29, 2015 1:36 am
by gromgsxr
was that with the sequenced batch fire off? were there any other changes? the tooth and composite logs look ok,
Re:
Posted: Wed Apr 29, 2015 9:56 am
by JakeusSnakeus
It was getting late last night and quite loud with all the banging lol. So I just packed it in, in the end but I've got more time tonight so ill keep logging and try again...
Re:
Posted: Wed Apr 29, 2015 1:11 pm
by gromgsxr
hmm banging is not a good thing have you got a timing light? you may need to confirm you are getting the ignition at the correct time.