MS3 dsm cas problem.

General support questions and announcements for MS3. See also MS3 manuals.

Moderators: jsmcortina, muythaibxr

242gt
MS/Extra Newbie
Posts: 21
Joined: Tue Apr 01, 2014 3:02 pm

MS3 dsm cas problem.

Post by 242gt »

hi guys
i am new to Megasquirt i need some help!

i have a volvo 242gt and i have convered from k jet to ms3 ( no ms3x) still running the volvo 4cyl b23 motor.

i have built my ms3 and tested it and it is ok ( tested using jimstim.)

i initially built it to use a standard volvo hall sensor dizzy, but now am using a mitsubishi 4cyl CAS with a adapter to fit in the standard dizzy hole in the block.

the issue i am having now is i cannot get a steady rpm signal via ms3... it will sit cyling from 0 rpm-150 and if i increase the pot on the jim stim it jumps to 5000-6000 them back down randomly.

all other sensors are working correctly tps ect....

i built the 4g63 circuit (input and spark) as per the manual.... ( http://msextra.com/doc/ms2extra/MS2-Extra_4g63.htm )

i am using 4 LS1 coils and no cam input.....

can any one help or point me in the right direction in regards to what to test/ check?
Last edited by 242gt on Tue Apr 01, 2014 3:44 pm, edited 1 time in total.
jsmcortina
Site Admin
Posts: 39587
Joined: Mon May 03, 2004 1:34 am
Location: Birmingham, UK
Contact:

Re: MS3 dsm cas problem.

Post by jsmcortina »

4G63 requires both "crank" and "cam" signals from the CAS - otherwise it won't get RPM.

James
I can repair or upgrade Megasquirts in UK. http://www.jamesmurrayengineering.co.uk

My Success story: http://www.msextra.com/forums/viewtopic ... 04&t=34277
MSEXTRA documentation at: http://www.msextra.com/doc/index.html
New users, please read the "Forum Help Page".
242gt
MS/Extra Newbie
Posts: 21
Joined: Tue Apr 01, 2014 3:02 pm

Re: MS3 dsm cas problem.

Post by 242gt »

jsmcortina wrote:4G63 requires both "crank" and "cam" signals from the CAS - otherwise it won't get RPM.

James

the Mitsubishi cas is bolted on to a adapter so it fits on to a b23 volvo motor....... ( http://yoshifab.com/store/index.php?_a= ... oductId=45 )

i dont see how it will not work as it is just two separate signals... one crank one cam....
jsmcortina
Site Admin
Posts: 39587
Joined: Mon May 03, 2004 1:34 am
Location: Birmingham, UK
Contact:

Re: MS3 dsm cas problem.

Post by jsmcortina »

242gt wrote:i dont see how it will not work as it is just two separate signals... one crank one cam....
That's what I was saying.

James
I can repair or upgrade Megasquirts in UK. http://www.jamesmurrayengineering.co.uk

My Success story: http://www.msextra.com/forums/viewtopic ... 04&t=34277
MSEXTRA documentation at: http://www.msextra.com/doc/index.html
New users, please read the "Forum Help Page".
JoseMiguel
Master MS/Extra'er
Posts: 652
Joined: Thu Dec 09, 2010 3:48 pm

Re: MS3 dsm cas problem.

Post by JoseMiguel »

242gt wrote:
jsmcortina wrote:4G63 requires both "crank" and "cam" signals from the CAS - otherwise it won't get RPM.

James

the Mitsubishi cas is bolted on to a adapter so it fits on to a b23 volvo motor....... ( http://yoshifab.com/store/index.php?_a= ... oductId=45 )

i dont see how it will not work as it is just two separate signals... one crank one cam....
that cas has 4 cables

1 is 12v
2 is ground
3 is "crank" signal (although it is in the cam, we consider it the crank signal)
4 is "cam" signal

here is the pinout

Image

CKP goes to the standard crank cable in the lower harness of your ms3 (only the white wire)

CMP goes to the cam cable in the upper harness of your ms3
242gt
MS/Extra Newbie
Posts: 21
Joined: Tue Apr 01, 2014 3:02 pm

Re: MS3 dsm cas problem.

Post by 242gt »

jsmcortina wrote:
242gt wrote:i dont see how it will not work as it is just two separate signals... one crank one cam....
That's what I was saying.

James

so your saying i cannot just run it as a crank sensor by its self? and not wire up the cam signal....?
242gt
MS/Extra Newbie
Posts: 21
Joined: Tue Apr 01, 2014 3:02 pm

Re: MS3 dsm cas problem.

Post by 242gt »

JoseMiguel wrote:
242gt wrote:
jsmcortina wrote:4G63 requires both "crank" and "cam" signals from the CAS - otherwise it won't get RPM.

James

the Mitsubishi cas is bolted on to a adapter so it fits on to a b23 volvo motor....... ( http://yoshifab.com/store/index.php?_a= ... oductId=45 )

i dont see how it will not work as it is just two separate signals... one crank one cam....
that cas has 4 cables

1 is 12v
2 is ground
3 is "crank" signal (although it is in the cam, we consider it the crank signal)
4 is "cam" signal

here is the pinout

Image

CKP goes to the standard crank cable in the lower harness of your ms3 (only the white wire)

CMP goes to the cam cable in the upper harness of your ms3

i am only using the crank signal, wired in to the tach input on the ms relay board, cam signal is not wired in as i am only running ms3 ( not ms3x)
jsmcortina
Site Admin
Posts: 39587
Joined: Mon May 03, 2004 1:34 am
Location: Birmingham, UK
Contact:

Re: MS3 dsm cas problem.

Post by jsmcortina »

242gt wrote:
jsmcortina wrote:
242gt wrote:i dont see how it will not work as it is just two separate signals... one crank one cam....
That's what I was saying.

James

so your saying i cannot just run it as a crank sensor by its self? and not wire up the cam signal....?
As I said, 4G63 ignition mode REQUIRES both signals.

If you want to just use the crank signal, then select and configure "Basic trigger" and use a single coil output.

James
I can repair or upgrade Megasquirts in UK. http://www.jamesmurrayengineering.co.uk

My Success story: http://www.msextra.com/forums/viewtopic ... 04&t=34277
MSEXTRA documentation at: http://www.msextra.com/doc/index.html
New users, please read the "Forum Help Page".
242gt
MS/Extra Newbie
Posts: 21
Joined: Tue Apr 01, 2014 3:02 pm

Re: MS3 dsm cas problem.

Post by 242gt »

Is it possible to use four LS1 coils in a wasted spark cop set up?
dontz125
Super MS/Extra'er
Posts: 4200
Joined: Mon May 11, 2009 7:14 pm
Location: York, ON
Contact:

Re: MS3 dsm cas problem.

Post by dontz125 »

Do you mean wasted spark with COPs (paired COPs firing together, 2 channels for 4 coils), or wasted COP ((paired COPs firing together, 4 channels for 4 coils and a waste of pins)? Either way the answer is 'Yes'; you could also use COP ignition with each coil firing sequentially.
QuadraMAP Sensor Module -- PWM-to-Stepper Controller -- Dual Coil Driver
Coming soon: OctoMAP Sensor Module
TTR Ignition Systems
prof315
Super MS/Extra'er
Posts: 3760
Joined: Sun Jan 18, 2009 3:13 am
Location: Melbourne, FL

Re: MS3 dsm cas problem.

Post by prof315 »

Regardless to use more than a single coil you must use BOTH CKP and CMP in 4G63 mode with that CAS
Linfert Performance/321 Motorsports
SCCA 2019 SM National Champion Crew Chief
SCCA 2023 FP National Champion Tuner/electrical engineer
100s of MS systems built installed and tuned
Support the developers!
jsmcortina
Site Admin
Posts: 39587
Joined: Mon May 03, 2004 1:34 am
Location: Birmingham, UK
Contact:

Re: MS3 dsm cas problem.

Post by jsmcortina »

As prof315 says, no you cannot run wasted COP without using both signals.

If you want to run wasted COP and only a single signal, then use something more accurate like a crank triggered 36-1 wheel. The 4G63 CAS is likely to be as inaccurate as a distributor trigger.

Summary - use BOTH SIGNALS or ditch the CAS.

James
I can repair or upgrade Megasquirts in UK. http://www.jamesmurrayengineering.co.uk

My Success story: http://www.msextra.com/forums/viewtopic ... 04&t=34277
MSEXTRA documentation at: http://www.msextra.com/doc/index.html
New users, please read the "Forum Help Page".
242gt
MS/Extra Newbie
Posts: 21
Joined: Tue Apr 01, 2014 3:02 pm

Re: MS3 dsm cas problem.

Post by 242gt »

jsmcortina wrote:As prof315 says, no you cannot run wasted COP without using both signals.

If you want to run wasted COP and only a single signal, then use something more accurate like a crank triggered 36-1 wheel. The 4G63 CAS is likely to be as inaccurate as a distributor trigger.

Summary - use BOTH SIGNALS or ditch the CAS.

James
Ahh ok thanks I am using a hi res disc in the cas

http://yoshifab.com/store/index.php?_a= ... oductId=46

So it should be more accurate?
racingmini_mtl
Super MS/Extra'er
Posts: 9128
Joined: Sun May 02, 2004 6:51 am
Location: Quebec, Canada
Contact:

Re: MS3 dsm cas problem.

Post by racingmini_mtl »

It should be more accurate but this also requires you to use both signals even with a single coil.

Jean
jbperf.com Main site . . . . . . . . . . . . . . . . . . . . . . jbperf.com Forum
Image
242gt
MS/Extra Newbie
Posts: 21
Joined: Tue Apr 01, 2014 3:02 pm

Re: MS3 dsm cas problem.

Post by 242gt »

i have built the circuit as per the link above, but i cannot get a rpm signal above 150rpm... ( testing with jimstim.

and when plugged in to the car i only get 1rpm signal....

i have checked the circuit and solder joints and they are all good.

any help would be appriciated
jsmcortina
Site Admin
Posts: 39587
Joined: Mon May 03, 2004 1:34 am
Location: Birmingham, UK
Contact:

Re: MS3 dsm cas problem.

Post by jsmcortina »

Please take and post a composite log.

Note that with the trigger disc you are using, "4G63" is the wrong ignition mode to select. The 4G63 is for the trigger pattern, not the outside body of the CAS.

You need to use "Toothed wheel" with "Dual wheel" and configure the number of teeth etc.
See: http://msextra.com/doc/ms3/trigger-whee ... alwheelcam

Note that the manual covers this as the Nippondenso CAS as your trigger disc is not an OEM fitment.

James
I can repair or upgrade Megasquirts in UK. http://www.jamesmurrayengineering.co.uk

My Success story: http://www.msextra.com/forums/viewtopic ... 04&t=34277
MSEXTRA documentation at: http://www.msextra.com/doc/index.html
New users, please read the "Forum Help Page".
242gt
MS/Extra Newbie
Posts: 21
Joined: Tue Apr 01, 2014 3:02 pm

Re: MS3 dsm cas problem.

Post by 242gt »

here is my msq
jsmcortina
Site Admin
Posts: 39587
Joined: Mon May 03, 2004 1:34 am
Location: Birmingham, UK
Contact:

Re: MS3 dsm cas problem.

Post by jsmcortina »

That MSQ won't work. You do not have a 4G63 trigger disc.

As I said in my last post, you need to use "Toothed wheel"

James
I can repair or upgrade Megasquirts in UK. http://www.jamesmurrayengineering.co.uk

My Success story: http://www.msextra.com/forums/viewtopic ... 04&t=34277
MSEXTRA documentation at: http://www.msextra.com/doc/index.html
New users, please read the "Forum Help Page".
242gt
MS/Extra Newbie
Posts: 21
Joined: Tue Apr 01, 2014 3:02 pm

Re: MS3 dsm cas problem.

Post by 242gt »

ok it's been a while...

i have now purchased ms3x card

and still am having an issue,
i have set ms up as per above ( toothed wheel)

i have checked my CAS and get 5v-0 when rotated.

i have 5v pull up i have tested it with 5v pull up and without the pull up. but still no RPM signal.....

can any one shed some light on the situation...
all other sensors are working correctly... intake air, water temp tps ect...

just no rpm...
jsmcortina
Site Admin
Posts: 39587
Joined: Mon May 03, 2004 1:34 am
Location: Birmingham, UK
Contact:

Re: MS3 dsm cas problem.

Post by jsmcortina »

:msq:
Plus composite log and tooth log.

James
I can repair or upgrade Megasquirts in UK. http://www.jamesmurrayengineering.co.uk

My Success story: http://www.msextra.com/forums/viewtopic ... 04&t=34277
MSEXTRA documentation at: http://www.msextra.com/doc/index.html
New users, please read the "Forum Help Page".
Post Reply