The MS Project - Switchable maps

Post Thu Oct 08, 2009 4:20 pm

I've finally made a start on my project to megasquirt the touring and try to map it to run both petrol and LPG (mainly for educational value). So far the board build has been relatively painless, but there are a few things I'm not 100% sure on:

The trigger wheel - is this a VR, Hall or optical sensor? I had assumed it to be a VR sensor...

Idle control - is the stock M20 ICV a PWM idle valve or a stepper? How hard is it to control using MS? I've seen a few posts saying it isn't necessary as you can compensate with spark/fuel enrichment anyways.

Also I've not been able to get an emulated O2 signal to show up on megatune. Everything else seems to be ok, so I have a feeling it's me being incompetent with the stim!

Any help is greatly appreciated!

Post Thu Oct 08, 2009 4:31 pm

Check out Flappysocks' guide www.diyefi.co.uk

My 325i Sport originally didn't have an ICV with its MS, and you needed to let it warm up for a short while, else it would stall. I then built an extension board as detailed on DIYEFI to drive the standard M20 ICV which improved things considerably.

Post Thu Oct 08, 2009 6:21 pm

So according to the guide the standard ICV is a 3 wire jobbie and will definitely require the PWM modification on my MS board? - I'm running MSII V3 so it shouldn't be too difficult to build in!

Still not a clue about the O2 signal, but perhaps it's too early to say!

Post Fri Nov 27, 2009 3:39 pm

Another question - MS only has one spark output so I will need an ignition module to feed to the coil pack. Is there one specific item I should look to get or will any 6 cyl specific module do? The coil pack is the GM vectra/omega jobbie...

Thanks!

Post Fri Nov 27, 2009 4:26 pm

Use a spark output driver board, such as those described in Flappysocks' site:
http://wiki.diyefi.co.uk/DIYEFI.co.uk_S ... iver_Board

Post Tue Jan 12, 2010 2:51 pm

Another question for the experienced MS users - has anyone got the E30 tachometer working with MS? Some say a transistor with a few resistors and others just an inline 10K resistor. Will probably look at taking the signal to the proto area, doing the resistor/transistor mod and taking the final signal out through SPR4.

Also where is the best place to pull this signal from?

Thanks!

Post Tue Jan 12, 2010 7:31 pm

My tach out is enabled but no matter what I tried it wouldn't feed anything to the tach. I found a easy fix and totally forgot about it. When I lose the oem ecu I will lose my tach again, I had my MS board ( Ms1 v3 ) modded for boost control, water inj, water pump and tach. When I redo my loom ( current is a hybrid ) and fit a ms only one I will have to figure out what it is.

Ant/Flappysocks have forgot more than I know about MS and do you know Phil @ extraefi?

Post Wed Jan 13, 2010 5:16 pm

Seems the best way to have the tach working is to run the Motronic unit at the same time, but it's not the nicest of solutions...

There's no way you can mess up the signal right? it either doesn't work at all or works perfectly (i.e. I'll never be in the situation where it's 200rpm off and don't realise?)

Post Wed Jan 13, 2010 5:30 pm

To drive the Tach off MS you 'll need to add the transistor output stage to JS2( or other)

then enable that output in "codebase and outputs"

then using MT label that output as tach out.

you MAY have to add a 12V pullup to the signal line, again Stuats wiki on DIYefi has all the info

It can and does work, occasionally I have to put a 0 to 5K trim pot inline to correct the tach reading, but rare to need it

3 wire idle valve works fine, use in warmup only and not PWM to simplify things a little, alternative is run more ign timing to prop the cold idle speed up ( enable IAT/CLT related ignition in MT )

HTH.

@Fozz, will email you back soon dude, just can't sit still long enough lol !

Post Wed Jan 13, 2010 5:46 pm

Ant wrote: HTH.

@Fozz, will email you back soon dude, just can't sit still long enough lol !

Don't fret dude, I could always pick up the phone if you're in later?

Post Wed Jan 13, 2010 10:33 pm

I got a bit of MS experiance and work in loughborough, let me know if you need anymore help.

Post Thu Jan 14, 2010 10:33 am

So I could use the original PWM valve as a fast idle valve?

I'm surprised the tach setup differs so much between cars! I would have thought if one person got it working, that same setup would work on everyone else's cars!

@chu346 - may take you up on that offer when the project gets moving!

the big challenge is going to be running the LPG setup using MS to control the stepper motor through the idle control maps... I'm not sure this has been done before, but it's worth a shot before splashing out on LPG injectors!

Post Wed Feb 17, 2010 10:30 am

Question again - what is needed to do switchable maps? A pdf I found floating in the ether says it's just a case of wiring a 12V ignition source (fused obviously) through a switch into one of the spare connectors (pins 3,4,5,6 on the DB37)...when the switch is closed, 12v goes to the ECU and switches maps...

Logic tells me that something isn't quite right here, but maybe I'm just paranoid!

Post Wed Feb 17, 2010 10:44 am

all the info you need is here dude : http://www.extraefi.co.uk/Drawings/PDF_ ... leMaps.pdf

Source is Phil Ringwood, he wrote the firmware and software so 100% pukka info there !

Post Thu Feb 18, 2010 6:42 pm

sweet! that was the pdf I found earlier so nice to verify it works!

I'm not getting this thing about enabling spare outputs for the tachometer - I found a wiring diagram on e30tech with the tach connected ultimately to pin JS1 on the MS board (V3)... does this automatically work or does that output need to be enabled using megatune?
-EDIT- just read it again, looks like it does need to be enabled, however I'm not finding 'codebase and outputs' anywhere in megatune!

also if I plugged the fast idle output into the correct pin on the bosch ICV and made sure it was powered, would it then open? If so which is the correct pin?

Sorry I'm asking all these questions! Just so many experts here - thanks guys!