Cineman - #01748 3.0lt twin turbo - Italy

[Bitsyncmaster]

Ok, maybe i think i have to use the PWM idle system 2wires of the MS, but use another output with the same pwm frequency but with the complementary pulse witdh...each of the 2 output to the side of the motor, center to 12v... it seems someone did it and it works...

That is correct. The PWM is a constant frequency 100 Hz for stock ECU, 61 Hz with mine. The second PWM driver is just the complement of the first.

[cineman]

Some MS friends gave me this schematic for controlling the 3 wires using the single Fidle output of the MS.
Does some tried or know it ?

http://www.glensgarage.com/3wire/Idl..._schematic.pdf

or this solution using a big power resistor:

http://www.msextra.com/doc/ms2extra/...ware.htm#Fidle

[Bitsyncmaster]

Some MS friends gave me this schematic for controlling the 3 wires using the single Fidle output of the MS.
Does some tried or know it ?

http://www.glensgarage.com/3wire/Idl..._schematic.pdf

or this solution using a big power resistor:

http://www.msextra.com/doc/ms2extra/...ware.htm#Fidle

The first circuit would work but you need a driver (from the MS) that provides 0 and 12 volts.

The second circuit would work if your drivers can provide enough current.

The resistor.....no

I use N-channel MOSFETs with diode and zener suppressors that drive directly from my micro (0 to 5 volts). If you use a power transistor you will need about 50 ma. of drive current for a typical hfe of 20. The idle motors draw about 500 to 1000 ma.

[cineman]

Hello guys,
i made the adapter for connecting the MS to my actual harness and did the first tests.
I had some problem having a good trigger input: i use a VR sensor, the oem renault one on the flywheel ( I use the Renix 44-2-2 standard ) i started with the 2 potentiometer all clockwise like the manual says and got no signal, then started turning then little by little clockwise until the ECU started to see a RPM signal, and got the car idling on the MS.
I did a lot of tuning on them, but i still think i dont have a very good VR signal :
I can hear every few secs the Fuel pump relays switch on-off, and the idle is very unstable and oscillate, i think for the RPM signal input wich switch the pump on and off. I also see the MS software going Synched-Not synched, when this appens.
I tried to open a little more the air but i still dont have a stable idle even at about 1000rpm.
Do you have suggest how to regulate that potentiometer ? I saw someone using an external signal amplifier for this kind of VR sensors, what do you think ?

I also use PWM for controlling the injectors, i started with PWM at 30% and 1.0ms of threshold, and it seems fine. Tried to lowered it, cars die at about 12% and 0,6ms but not start anymore after, so i think i keep the suggested numbers. Changing this dont change the quality and oscillation of idle, so i'm quite sure is more an RPM input problem
Thanks guys! This seems to be a very fun project I get excited every time i see a real time numbers on the PC lol

[cineman]

Ok... found the potentiometer problem, i just soldered them the opposite way
I will do more test in the evening, I'll let you know!

[cineman]

Hello!
Some little progress during this times. I got the WUE, cranking and priming curves quite good and working with frozing out temperature, and even the fuel maps for now seems not so bad, but i have just the narrow band sensor on, now, wich is btw working and making some EGO corrections when all is warmed up.

The problem i have is still a random big "miss" , suddenly die for a second, on the engine, when accelerating, cruising or so. I thought it was the VR sensor sensibility problem, but now that seems to work and read good and it has good graphs in the logger, so maybe could be a power supply problem ? I get my supply from my old main supply of the other ECU and that one was working, but i see in fact some times the volts reading of the MS read peaks of quite high voltage ( around 16 volts )
Do you have tests to try out to find the area of the problem ?

I attach also my MSQ file
Cineman_3.0TwinTurbo_2012-02-24_21.31.42.msq

[Spittybug]

Cineman, I wasn't able to open your file for some reason. What version is it? In any case, it sounds like maybe you are getting a reset.

Is your fuel pump on the same circuit as your Megasquirt? It's not a good idea since mechanical devices are "noisy" and can disrupt the MS. I ran them on two separate circuits. For the conversions I am now helping with, we run 2 fused wires from the battery; one dedicated to the fuel pump relay and the other providing power for the MS, the O2 sensor and the injectors. I haven't heard anyone having problems with the mechanical fuel injectors creating noise on that circuit, but I suppose it is possible.

Check the obvious too, the grounds. All MS grounds need to go to the same spot. Make sure that block is well grounded and that your negative batter cable is firmly connected at your trailing arm bolt (my ring connector was free spinning on the wire!).

[opethmike]

Cineman, I wasn't able to open your file for some reason. What version is it? In any case, it sounds like maybe you are getting a reset.

Is your fuel pump on the same circuit as your Megasquirt? It's not a good idea since mechanical devices are "noisy" and can disrupt the MS. I ran them on two separate circuits. For the conversions I am now helping with, we run 2 fused wires from the battery; one dedicated to the fuel pump relay and the other providing power for the MS, the O2 sensor and the injectors. I haven't heard anyone having problems with the mechanical fuel injectors creating noise on that circuit, but I suppose it is possible.

Check the obvious too, the grounds. All MS grounds need to go to the same spot. Make sure that block is well grounded and that your negative batter cable is firmly connected at your trailing arm bolt (my ring connector was free spinning on the wire!).

+1. I was having a huge number of reset problems until I followed Owen's advice. Mr. Malbec is THE man on this topic.

[Spittybug]

In the immortal words of Garth, "I'm not worthy!!!!!!!!!"

Hey, I'm a believer in modernizing the guts of the car while maintaining as much of the classic aspects as you would like. The fact is that most people either can't diagnose the various components of K-jet themselves or can't afford to have others do it for them. I have nothing against the carburetor camp, but to me, that's a step in a direction I would rather not take. If I can minimize the moving parts, the things that will wear or the things that fewer and fewer people understand and can help with, all the better. There are diagnostics to trouble shoot software problems and plenty of help on forums. If you know injectors are injecting, it's merely a case of making sure they do it correctly. Tuning your car with software is a hell of a lot better with a laptop than it is with a wrench in my opinion! I wholeheartedly encourage each of us that are EFI'd to post their .msq files and to maybe also snapshot their tables. I haven't fully explored the software aspects of reading .msq files and loading into projects..etc... but it isn't hard to copy/paste tables. VE, AFR, ADV, ASE, WU. Done.

Rock on dudes!

[opethmike]

Once I get ~100 miles or so on my newly Spec 2'd engine, I'll post the MSQ for it. Should be useful as a base tune for other Spec 2s, or for a Stage 2, which is similar, but not as aggressive.