ms doesn't see the rpm?

I finished wiring up a 5.9 magnum.
the distributor is a little different than stock. it has a shutter wheel in it instead of whatever is normally in a magnum distributor.


based on the wiring diagram diy auto tune supplied, I wired it in with all 3 wires.
common 5 volt, and then specific ground and sensing line on their shielded wire.

I can see voltage changes in the sensing line. but the tuner studio software doesn't seem to see anything.
I have a resistor wired in to the sensing line as well from how it was previously used.

sent them an email since there is no way to call, but wondering if anyone has any ideas on what to check.

Need to see the pickup. That saud, stock magnum would have been a hall effect type sensor. If the new one is 3 wire it is likely hall effect as well.

magnum engines get the engine rpm from the crank sensor, distributor is basicly used for the injectors (aka cam sensor)

this is the pickup.
I realize it is the "cam' sensor, it worked for the old setup.
trying to make it work for the new.

it might just be that I don't have the right settings, or I didn't wire it right. not sure at this point.



the plug. is a 3 wire.

need a 1k ohm pull up resistor between the power and signal pins. I had to do it on mine (using it as a cam sensor). It's the two outer pins.

oh another tech tip is if you want to test it you'll see the hall sensor switch state when you pass a razor blade through it.

The Magnum of course should be a ported inj with 8 inj and not throttle body inj. Just asking to be sure and are you using the Mopar eng controller ? The Mopar ones would always use a 5 volt signal wire and then one is ground and the key on pull up voltage wire that powers the hall effect up could be from 5 to 12 volts as Mopar has used 5 , 8 , 9 and 12 volts on the key on voltage wire that powers the unit up. I dont remember which yours would have as it would depend on what controller is uses. On the Mopar controllers the crank sensor gives the RPM signal on that type. Actually on the Magnum V/8's you could unhook the dist pickup after the eng is running and it will keep running as once the PCM knows the firing order (from the cam sensor-the dist) it remembers it and keeps going through the same firing order so it does not need to look at the dist pick-up signal until the next start-up. Ron

I don't know the size of the resistor, but painless used one too. it is already wired in. I clipped the wiring with it still intact.
I will double check but it seems correct.
383 man, this is not quite stock anymore.

the engine and injectors and throttle body are stock.
it is using gm sensors for temp the stock tps, but the distributor has been modified with that shutter wheel and sensor.
it was running an aftermarket efi setup and I am replacing it with another efi setup, just trying to figure out why it won't get a signal.

Not sure if this is what you need. I used one of these to pick up an rpm signal for the digital tack I used with the 5.7 in my 55 pick up. I picked the signal up off of one of the injector trigger wires. Should work on your set up.
http://www.msdignition.com/Products/Accessories/Tach_Adapters/8918_-_Tach_Signal_GMR_Pickup.aspx

not sure that would help. it isn't firing the injectors on crank as far as I can tell because it isn't getting a cam signal to fire them at all.

383 man, this is not quite stock anymore.

Gotch ya. I have not fooled with the aftermarket EFI stuff much at all. All my years were at the Dodge dealer. Thought it may help if you were using mainly factory Mopar setup. Sounds like some of these guys have messed with it. Good luck to you. Ron

goldduster318- I checked and the resistor is wired like yours.

with the computer unplugged, I get 2.17 ohms on the 20k scale. So 2170 ohms between the two outer pins.
.3 up each line to the connector. so I think I am good there.
problem is, I am not sure what settings to put in the tuner studio for this setup.

for those of you that have a running megasquirt with ignition, can you tell me if your sensing lines read full voltage or just partial?

I haven't been able to get a response today from diy, so I guess they are closed for the holidays. but since I only get full voltage when I disconnect the ecu, I am begining to thing something is wrong with the box I got.

Andrew are you on Facebook? There is a Megasquirt group that I believe is hosted by DIY. There is some decent help on there a lot of it from DIY Employess and other folks from around the world.

I am using a crank trigger on mine so I am not going to be much help. I use a 36-1 wheel and a Jeep cam sensor on my 360.

no, not on facebook.
but I did join the msextra forum.
they decided that the jumpers were wrong based on the current manuals.
Unfortunatly I broke some pins changing the jumpers so now am stuck till I can get replacments or a new board.

Hate to hear that! Good luck!

Any Luck?

I got a partnumber from diy on monday for the replacement pins. Got it ordered from mouser same day. They delievered it yesterday, and I was able to replace the pins today.
Tested and got 5 volts now out of the sensor line as expected.
I could see rpm's on the tuner studio during cranking.

So progress. Now I have to see where the timing is. but probably won't get to it till this weekend.

Thanks for the help.
Man this has been a pain. It almost makes me wish I had spent the extra for ez efi instead.

Shame it's been so hard for you. I spent the bucks on the MS3 Pro...doesn't have any jumpers to set...all software. I had totally forgotten about that on the earlier/less expensive versions.

yeah, that nickle and dimes it everytime. the upgrade to ms3 was over 100 bucks closer to 200.
put me half way to the ez efi.
But ez might not work with my spark control. so I figured I was better off with ms.
was never going to use the extra features on ms3, but had I known it was easier to wire I might have gone that route too.
eh, live and learn and hope to never have to do it again.

well after the jumper change, it fired up.
It would not stay running though unless I feathered the throttle.

I got it to warm up that way and then it just hunted around forever.
not sure if I have the iac wired right or if it is something else.
but it is more progress I guess.

anyone have the diagram for how mopar wires the iac motors?

To set your base idle, I would pull the plug on the throttle stop screw and use that to set your idle speed just like a carb. The IAC should be used for warm-up fast idle, not base idle control. I would get the IAC closed, then disconnect it and come back to it later.