Steve's Megasquirt/tunerstudio Help Thread

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You can just upload the datalog here by clicking upload a file. And I want to give a shout out to @a91what. He's been helping me tune my DIYPNP. A little more tweaking and I'm all set! Thanks Steve!
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Man, I've got a problem Steve. My car hasn't started in the last couple weeks. I thought I had done something to the tune ( being the idiot I am ).

I compared my current one to the one you sent and the only changes were where I inputted my required fuel in basic settings. So, no real changes were made....timing offset was still the same at 10.

With all that figured out....I data logged in MegaLogViewerHD. Found the MS is only reading about 125 cranking rpm. Ofcoarse , my cranking rpm is set to 450.

Now, I just put a new 1000ca AGM battery in last weekend and I know its cranking faster then 125 revolutions. My distributor pick up is new and so is my TFI module.

I did wire a tach to my coil... Do you think that could be causing some type of interference ? I'm going to remove it in the AM but wanted to know what you thought about it. I also did hook it up correctly... I think...:thinking:

Figured I'd document this issue in case there are any other dummies like me out there.

Edit; my engine running threshold is 450rpm.
 
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Make sure the settings are set to 8 cylinders. Also there is a tach output on the main board in the MS.... use it for the tach signal, if you unhook the tach that's wired in and get a proper signal to the MS then problem solved.

BTW great job using the data logger for troubleshooting I'll get you learned yet.:D
 
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Thanks again, Steve !

The tach and everything works. I had to reset my timing, again. Smh

The car is alive. Think I'm learning....slowly. The tach works fine... My cranking rpm is a hair under 200rpm. That rpm seems normal with the research I've done.

All of my spark plugs were fouled from cranking with the required fuel at 10.3. My fuel pressure is only 44psi and I have 42lb injectors in a 331. Cleaned them and they're OK.

Haven't data logged yet.
 
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This is my datalog from my start. After a couple minutes my rpm hits the roof vacuum comes up, too. I have no idea whats causing this.

it was doing it previously...my temp stays steady around 200.....195 thermostat. I can't find any vacuum leaks but wont pull more than 10 vacuum until I hit the rpm surge.

Any help would be greatly appreciated. This surge is the reason I started screwing around with the idle. Should I just auto tune for the driving end and leave this alone for now ? its kinda scary when the rpm starts shooting above 2500.
 

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just got done looking at the datalog and if you chart rpm with PWM idle duty you can see the car idle away at 900 rpm with the iac open 100%.... when the duty cycle drops the rpm comes up.... this is backwards to what should be happening. the valve is working in reverse.
go into startup/idle then [idle control] on the right side of the box in pwm idle settings change the valve mode.

this should fix the problem the mode should be set to "normal" 0% =closed

on a side note the datalog shows you idle very lean in the 20afr range please verify this.
 
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The cruise control uses a separate module ( under left side of dash ). The module controls a vacuum reservoir behind the left fender. The cable from that hooks up to the throttle body.

I'd have to check wiring schematics but I'm sure it could be made to work with MS.

There are aftermarket cruise control kits that work off the same principal...on/off switch, set/resume switch, vacuum hose, clutch switch, brake switch, cable to TB, and module.

I believe the cruise control in fox mustangs works independent of the ECU.
 
Man, I feel like an idiot...( most of the time I do ):(

I just added PWM to the datalog graph and instantly saw the problem...smh. I'll change those settings and check out how he runs tomorrow after work.

The lean condition is from an air leak at the v band behind the turbo before the WB. I planned on fixing it when I put the down pipe sleeve on. Starting and idling has been my focus thus far. I'll fix it before I really drive it.:burnout:
 
Just checked my idle control settings in TS. The valve mode is set to normal, 0℅=off.
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I switched it to inverted, 100%=off. We'll see what happens tomorrow. I'll post a catalog.

Thanks, Steve !!!
 
I've read were people had to reverse polarity with certain IAC valves. I'll see if I can command it open and closed and watch what it actually does.
 
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