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Calling Shelby, Indiana, Phinko, Scott87Star...All the big guns...HELP!


polarisman14
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Not yet but it's on its way. The thing that doesn't make sense to me is that I thought you had to tell TS whether it was a sine wave or square wave so even if you did swap the tach adapter in it wouldn't be able to interpret the sine wave signal properly, would it?

 

Either way there's a hurricane coming Sunday and it looks like we'll be getting hit with it...Maybe it'll drop a tree on my car and I can buy a working MPI one with the insurance money, lol.

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Not yet but it's on its way. The thing that doesn't make sense to me is that I thought you had to tell TS whether it was a sine wave or square wave so even if you did swap the tach adapter in it wouldn't be able to interpret the sine wave signal properly, would it?

 

Either way there's a hurricane coming Sunday and it looks like we'll be getting hit with it...Maybe it'll drop a tree on my car and I can buy a working MPI one with the insurance money, lol.

did you pay for the tunerstudio registration to get the full version?

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Not yet but it's on its way. The thing that doesn't make sense to me is that I thought you had to tell TS whether it was a sine wave or square wave so even if you did swap the tach adapter in it wouldn't be able to interpret the sine wave signal properly, would it?

 

Either way there's a hurricane coming Sunday and it looks like we'll be getting hit with it...Maybe it'll drop a tree on my car and I can buy a working MPI one with the insurance money, lol.

 

If I remember correctly

The square wave is a pulse and is used more in on / off frequences (DC currents)

The sine wave is a smooth repetitive (transitional) oscillation and in the nature of its form it blends and is not distroted as easily by interference

(AC currents)

Edited by Metric-man
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Here is the output from a tach adapter assisted CR125 module.

 

http://picturehosting.com/images/oblique9881/cr125tachadapt.jpg

 

 

It is also square wave, you may be confusing sine with the output of a VR sensor which is both positive and negative but in no means is it smooth.

 

Scott

Edited by scott87star
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Here is the output from a tach adapter assisted CR125 module.

 

http://picturehosting.com/images/oblique9881/cr125tachadapt.jpg

 

 

It is also square wave, you may be confusing sine with the output of a VR sensor which is both positive and negative but in no means is it smooth.

 

Scott

 

 

whats up with the double spikes at the top of some of the switch points ?

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whats up with the double spikes at the top of some of the switch points ?

I think those are spikes from the coil.

 

 

What does the signal look like with out the adapter?

 

Are you are using an 8910 ?

Edited by Metric-man
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Here is the output from a tach adapter assisted CR125 module.

 

http://picturehosting.com/images/oblique9881/cr125tachadapt.jpg

 

 

It is also square wave, you may be confusing sine with the output of a VR sensor which is both positive and negative but in no means is it smooth.

 

Scott

 

thats the money shot! cr125 w/tach adapter = signal found!

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Yeah, I'm curious if that one had a signal without it or not. Either way I'm still waiting on mine, it'll be here sometime early next week and I'll be putting it in ASAP.

 

The wiring diagram still kinda confuses me though...How does it get wired in? Is it spliced in and where? In between the dizzy and main harness, between the ignitor and weatherpak, etc...Just trying to figure out where to mount it on my specific setup.

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Yeah, I'm curious if that one had a signal without it or not. Either way I'm still waiting on mine, it'll be here sometime early next week and I'll be putting it in ASAP.

 

The wiring diagram still kinda confuses me though...How does it get wired in? Is it spliced in and where? In between the dizzy and main harness, between the ignitor and weatherpak, etc...Just trying to figure out where to mount it on my specific setup.

 

Does your fuel pump still turn on ?

 

No flooding of the cylinders correct?

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you need to stop worrying about where your going to mount things and just make it work. Make it pretty later. Did you even test anything yet? We cant reach through the computer and fix it for you.
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I was thinking he might go to Chat but with all of us giving suggestions his screen would probably lock up,

That probably what he is doing testing stuff..

 

I have to go clean my garage so I can get some work room..I'll check back later.

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My fuel pump does turn on, 42psi fuel pressure while cranking. And it may be flooded right now because of all of the start attempts but I still have no spark so that doesn't matter. Like I said, it has power and when the MS first gets power it gives the engine the prime pulse which squirts a little fuel in to purge the fuel system. However, with no spark, it won't fire anymore.

 

Phinko, I have every intention of making it pretty later. I'm just asking how it gets wired in--I don't really understand the wiring diagram that was posted earlier. I know they're only two wires, just not sure where they're supposed to go in my particular setup.

 

I've tested a shitload of different things (a lot of which are in PMs between Scott and I so I don't blame you for accusing me of not doing anything) and so far everything indicates that things should work. The voltages and continuities are where they should be, there's just no signal getting through. Hopefully the tach adapter will fix this, but I just need to know where to run the wires and whether it's supposed to run "through" the tach adapter (in-line) or just splices into a preexisting wire (the equivalent of using a scotch-lok style connector) based on how Scott said my system functions right now.

 

And Metric, I've already spent some time in Chat and gotten some suggestions there. I just can't do much else until I get that tach adapter in the mail. I tried to purchase it locally but NOBODY had it and it would have to be special ordered. That's what I get for living in NH I guess.

Edited by polarisman14
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http://i761.photobucket.com/albums/xx254/notstock88/ECUInstall1.jpg

hooking it up is just as it shows - leave your current set up the way it is and just bare a little wire on the 12v and solder the tach adapter lead on. Then do the same with the signal wire. it will be quick and easy.

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Nah, after Shelby said it wouldn't work right if it wasn't grounded I figured that'd mean it wouldn't work. Plus it's raining out right now so I can't do much of anything. What specifically am I doing? I don't have the o-scope right now, is there anything else I can do that would benefit me without that?
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And Notstock88, when you say the +12v you mean the one that is yellow with a black stripe on the stock harness, right Or could I just crimp a ring lug on it and use the positive from the coil? And the signal wire is the black wire? Should be pretty easy to do either way, just need the damn thing to get here!! I'm gonna be super bummed if it doesn't work, lol... Edited by polarisman14
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Running MS2 V3.0 with the V3.11 firmware, set up for fuel and ignition control. TunerStudio V1.004 and the most recent version of MegaLogViewer for viewing datalogs.
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the jag on the bottom following the square wave if you notice those with a double spike have less coil energy after the fireing is over,, could just simple be dirt inside the dist interfering with the signal as it's rather random
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http://www.msdigniti...ge.aspx?id=3298

 

 

Import Vehicles

 

If your fuel injected import vehicle fails to start or the tachometer reads erratically, you will need an MSD Tach Adapter PN 8910. If the PN 8910 is installed and you have spark but the vehicle will still not run, you will need a special Tach Adapter. Contact MSD Tech for the correct Adapter.

In some instances, after installing an MSD Ignition control unit on an import vehicle may result in a no-start situation or a erratic tach. Depending on which MSD Ignition was installed on the vehicle a tach adapter will be required to remedy the situation.

 

A no-start situation may result from a smart ECU not sensing coil current as a result not energizing the Fuel pump. The 8912 tach adapter will develop an artificial coil current to sadisfy the Smart ECU’s requirement to energize the Fuel pump again.

 

An erratic tach or non working tach is a result of the factory wire being removed from the coil -. The adapter will also develop a tach signal to satisfy the tach again.

 

If a DIS controller was installed, a PN 8912 will be required.

 

The ECU must have the tach signal from the - coil terminal or after the ignition key moves from "start" to "run" the fuel pump portion of the control relay shuts down. If you have that going to MS you'll need to send it to the stock ECU too, OR take the fuel pump relay wire from MS and cut the white wire with the red stripe at the conrol relay and connect it to MS. You say it starts then dies so it has spark and fuel for the prime pulse but afterward dies. It sounds like its because you still have the stock ECU controlling the fuel pump relay inside the control relay and there's no ignition (tach) signal to it so the fuel pump shuts down after you release the ignition key from the "start" position.

Although I don't doubt your theory, the car USED to start for a few seconds then die out when it was running fuel only control. At that time the tach on the dash of the car also worked but there was still no RPM being registered in TunerStudio and therefore nothing to continue driving the injectors past the prime pulse. The car had spark.

 

The ignition signal is also being controlled by MS now. At this point the car does not start whatsoever, has no spark, no RPM signal, no tachometer movement in TS, and the only time the tachometer on the dash does anything is when the key is first switched into the on position. It jostles a bit. No movement when cranking so that tells me the in-car tach has no tach signal either. I believe the reason why the OEM ignitor is still part of the system is to be able to tell the fuel pump to keep running, no? I have a fuel pressure gauge and it reads a steady 42psi when cranking.

The ignition switch powers the control relay and when the switch is in the cranking position it causes the pump relay to close and after the ECU gets a tach signal from the - coil post (nothing at all to do with the dash board tach you don't even need it and it runs off another wire, its from the little metal thing with the black and white wires from it ) and as you are starting the car the tach signal begins and the ECU also holds the pump relay closed and when the ket moves from start to run the pump relay stays closed.

Edited by Metric-man
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So if that doesn't work then I may need an 8912 instead? Does this apply for other ignition management systems or just the MSD box? As noted before, I'm not using one of those so I don't know how much of that applies to my setup.
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I wish I had snapped a screen shot of Matt's actual ignition output, I gotta start doing that for these kinds of troubleshooting reasons. But this is what it looked like on the scope, this is actually a real Caravan module but an aftermarket cr125 with the megasquirt documented 5 V pull up looks the same.

 

http://picturehosting.com/images/oblique9881/mitsumodule.jpg

 

 

 

And for the curious, this is the output from an aftermarket (non Mitsubishi) cr125.

 

http://picturehosting.com/images/oblique9881/cr125.jpg

 

For the technically inclined, the ignition input triggers an optoisolator on the megasquirt board. An optoisolator optically isolates anything happening on the ignition circuit from the processor so it can't get damaged, it is nothing more than an LED mounted in a chip. The voltage difference on/off fires the LED, a light sensor in the chip sees the LED light and sends a signal along to the microprocessor that an rpm signal is incoming. You can plainly see from the scope traces that the aftermarket cr125 does not have enough voltage by itself to fire the optoisolator so to make it work you either connect the MSD tach adapter (how FIP had everyone do it since their board didn't support mods to the igntion circuit) or you add a pullup voltage to the ignition circuit. 5 volts is normally plenty of voltage.

 

Scott

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