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Yup
 

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In Yates' case he had a plug-and-play version of Megasquirt for a Mustang, but did not have the adapter harness that normally comes with. The adapter harness has the required pull-up resistor for TFI, it is not internal to the plug-and-play computer. So he did not have computer controlled timing until he added that resistor.
But unless I misunderstood what he said, he has the same exact setup as me. A 3.57 board and a home made wiring harness (not factory) and no adapter harness.

So how could he have the pull up resistor? I thought the 3.57 board didn't have a spot available for it regardless if it was a PNP or not. Maybe I'm missing something here.

But judging from what he said, pulling spout and the car dies, the computer is seeing something.
 

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Well 1st things 1st, the car should still run with the spout unplugged. Let's start there and get that base timing to 10 degrees.

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So how could he have the pull up resistor? I thought the 3.57 board didn't have a spot available for it regardless if it was a PNP or not. Maybe I'm missing something here.
There is no dedicated set of pads for adding the resistor - but you can put the resistor on top the board, wrap it in heat-shrink tubing, and connect one end to S12 and the other end to the center hole of Q16.
 

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But unless I misunderstood what he said, he has the same exact setup as me. A 3.57 board and a home made wiring harness (not factory) and no adapter harness.

So how could he have the pull up resistor? I thought the 3.57 board didn't have a spot available for it regardless if it was a PNP or not. Maybe I'm missing something here.
To your question, there was confusion in your case b/c you had a "plug and play" computer, so we all assumed everything would be in the computer itself. We later figured out that the plug and play aspect considered the cpu and the harness it comes with. They're sold together so that's not unreasonable.

His isn't (or he didn't tell us it was) so it had to be "built" in a manner of speaking. In that process you can certainly solder in the pullup resistor inside the case. There isn't a dedicated place on a v3.0 board either.
 

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Discussion Starter · #26 ·
This might be a MS ecu issue. After the resistor it started and same thing I went right off the tfi and joined the red 12v to the pink spout wire. The car will not start with the spout connector disconnected. I did a pin to pin test and everything seems fine. Key on spout connector has 12v, when cranking voltage dies then comes back to 7-9v. I have to get my scope and see whats going on with the signal and see if i can see the square signal. But as of now the MS will not communicate with Tunerstudio. I have tried restarting the computer, re communicating, check the wires, usb etc. I have another MS this ones a MS2 version 3.0. The one i have was not made by me and I am not a fan of the soldering job done by the builder. I will try this and report back and solder the relay as per what Matt said.
 

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The car will not start with the spout connector disconnected.
Not attempting to ignore anything else you wrote, but if your engine will start with the spout in, but will not start with the spout out, this is the 800 pound gorilla that you need to take care of 1st.

Your engine can and should start with the spout unplugged. You will still get spark without the spout plugged in, you just don't get extra computer-commanded timing advance.

If you don't have a hand-held remote starter switch (like this), ask a friend to help and see where your timing is when the engine is cranking, and the spout is unplugged. You want to get it around 8* - 12* advance. Anywhere in that range is fine and it makes no difference what it is specifically, as long as you get it in that ballpark.
 

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Discussion Starter · #28 ·
lol yea no one likes a 800lb gorilla, I have no spark now the TFI seems to be dead :shakehead, there no spark to the coil and the negative side is not pulsing. I am going to get a new TFI and hall sensor for the distributor and am hoping that this has been a odd signal from either or that has been giving me the trouble, especially since I highly doubt that they have ever been changed and the car is a 1994.
 

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lol yea no one likes a 800lb gorilla, I have no spark now the TFI seems to be dead :shakehead, there no spark to the coil and the negative side is not pulsing. I am going to get a new TFI and hall sensor for the distributor and am hoping that this has been a odd signal from either or that has been giving me the trouble, especially since I highly doubt that they have ever been changed and the car is a 1994.
Roger that. Not good that the negative side isn't pulsing. Just realized you have a '94. They have a different TFI than the foxbodies, and if you don't set up things right you can burn up coils and modules. Been there done that. :)

The short of it is that you don't used fixed duty cycle of 50%, you use standard dwell. I'll check my settings for you when I get home.
 

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Alright, so the TFI module on the 94/95 mustangs is the computer controlled dwell type. So instead of only sparking when it sees the SPOUT go to ground, it also looks for when the SPOUT goes to +12 as a signal to begin charging for the next spark.

With these modules you don't want to use a 50% fixed duty cycle on the SPOUT, or you get far too much dwell times at lower RPM that will eat up modules and coils.

This should get you started.
Under Basic Setup -> More Ignition Options:

Use Prediction -> 1st Deriv Prediction
Cranking Dwell -> 2.5
Dwell type -> Standard Dwell
Maximum Dwell -> 2.5
Acceleration Compensation -> 1
Maximum Spark Duration -> 0.1

You can turn on overdwell protection if you want. My understanding is that underdwell protection isn't really implemented.
 

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Discussion Starter · #31 · (Edited)
Ok, changed the setting as you said and put the new tfi. The car starts with or without the spout connector now. I also installed the resistor pin3 to pip on the tfi, and the timing stays the same and turning the distributor makes a very little change the MS seems to have a number in its memory and try's to keep as close to the number as possible. The MS is calculating or using the wrong timing this makes no sense why i can't adjust the timing below 30 according tunerstudio and the car shuts down.

I also had a a buddy of mine come by that just got back into town and he had a picture of when i first had the car started, he happen to have a picture of the tunerstudio and guess what 15 degrees and the car idled. When i first started the project I was doing a little then life got in the way for a few days or weeks and then I would go at it again so I don't remember the car really running correctly. I also forgot when I first had the car and i was tweaking the injection and timing I drove down the street with him and the car was ok until about 2500rpm's so we cruised a little. So there must be a problem with the MS there's nothing else I can think of especially that the tfi and pickup sensor is new.

Also I tried my buddies MS 2 version 3.0, His is setup for a edis trigger system on a MR2 but when it cranks its about 15 degrees mine spikes 38, also the 3 led's when i have the key on the ON position blink quickly then go off and only react when cranking, mine however stay lit and then also react when cranking. Needless to say the timing does not jump to 30's.

Any ideas on where to look on the MS itself?
 

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What is the timing now, according to a timing light, withh the spout unplugged?

What is the setting of your trigger offset?

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Get that number, spout out, with the timing light when you get a chance.
 

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Oh sorry, I thought you had it running. It's okay to get it going with the spout in... just need to know where it's at when the spout is out.
 

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Discussion Starter · #38 ·
It is running just the idle flutters up and down hard to determine a degree. I'll try and get it to idle and get a degree. Could it be anything with the MS or am I way off and its not possible, since it seemed like everything was working correctly a while back? I have the MS out of the car and case off so If there's a dedicated circuit for timing i rather check it before i throw it back in the car.
 

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It's not that it couldn't be the MS, but we need to build a foundation of known quantities first, otherwise we'll have no direction in troubleshooting.

With the spout unplugged, even though the engine may be all over the place, the timing won't move except for a little bit due to timing chain slack/stretch... assuming the distributor itself is tight and doesn't rotate.
 

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Discussion Starter · #40 ·
Fair enough, is there anything else to check while car is running? want a datalog? snapshot? or in the scenario the number is close to what your looking for what would be next step to look at and the reverse what if its way off? I only get to do this 1 time a week if i am lucky so doing as much as possible would work for me.
 
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