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420A New Megasquirt install and no spark or fuel

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biglady112

15+ Year Contributor
1,871
390
May 20, 2004
Commerce City, Colorado
I am about fed up with this system and their customer service. I bought all the extra stuff that was needed which took three different purchases. Spent all this time wiring in all the BS to make the system work. I am not getting any spark or fuel to the engine. I have the quadspark, the expansion card and all that I was told I needed and nothing. I am not getting any kind of RPM signal while cranking. All the settings appear to be correct to me.

Any guru's in here want to take a stab? I knew I should not have taken this project on. It is just dragging on. COuldnt be the simple 4G63 and already be down the road.


It looks like I cannot upload the msq files here. I am happy to send them to anyone who can help. Beyond fed up here.
 
This is slightly discouraging for me. Had been contemplating getting an MS system for a future project, but had worried about the support for less than normal platforms...

Wish I could help, but am useless as I never tinkered with one intimately.
 
This is slightly discouraging for me. Had been contemplating getting an MS system for a future project, but had worried about the support for less than normal platforms...

Wish I could help, but am useless as I never tinkered with one intimately.

I have had my MS for almost 9 years now. I have been able to troubleshoot any issue/question with a bit of googling. The MS manuals are organized much better now a days compared to 2011.
 
I’m assuming you are running the MS3x. Did you get the preassembled main board?

DIYautotune has an article about what is needed for mods on the MS3X for the 4g63. Scroll to the bottom. It starts with MS1, then 2 then goes to 3.

https://www.diyautotune.com/support/tech/install/dsm/megasquirt-your-4g63/
This is for a 420A. Thus a 420A subforum. I rewired the crank and cam sensors from 5v to 12v this morning and still nothing.

My advice is look for another system. The software is easy to navigate, the bullshit you have to do to make this ecu work with the car is terrible and getting help has been even worse. I would have done a universal AEM if it was going to be this much of a hassle. Not impressed with mega squirt at all.

And yes, this is an MS3X stupid ass setup.
 
This is for a 420A. Thus a 420A subforum. I rewired the crank and cam sensors from 5v to 12v this morning and still nothing.

My advice is look for another system. The software is easy to navigate, the bullshit you have to do to make this ecu work with the car is terrible and getting help has been even worse. I would have done a universal AEM if it was going to be this much of a hassle. Not impressed with mega squirt at all.

And yes, this is an MS3X stupid ass setup.

my fault. Just knew you typically did 4g63 stuff. Send me your file and I can check it against mine.

the sensors should be fine on 5v, stock they are on 8 volts.

DIY does have an article about the 420a. What mods have been done to the inside of the unit?
https://www.diyautotune.com/support/tech/install/chrysler-dodge/megasquirt-your-neon/
 
I followed that article and I am still in the dark here. There are no mods to the board other than ordering the MS3X board and installing it. All the jumpers were set to what was asked. And even then I didn’t have to do anything.
I have also posted this on the msextra forum with the files there.
 
This is setup with their quadspark. The wiring wasn’t difficult. Just nonsense that wasn’t needed to make it work. And yet, it still won’t.
 
Also, there are no wires from the stock wiring harness going to the engine. The stock ecu has been completely removed. The mega squirt wiring harness is all there is as far as the engine is concerned.
 
For the crank sensor do you have the shielded wire used correctly? I know I stumbled there a bit because I had never used any before at that point. That shielded wire should provide the ground and signal for the sensor.
 
The shielded wire is not grounding the sensor. The bare wire is unterminated currently. The black wire coming out of shielded bundle per the instructions is where the ground is wired to. For both cam and crank.
 
Yup the shield wire doesn’t connect to anything. Do you have the cam and crank both on that same ground? Or just to each respective shielded wire pack?
 
There is only the one shielded ground. Even with the MS3X. So they both go to that.
 
Only do one ground to the shield wire ground. Disconnect the cam from it and see if you can read the crank signal. I ran a shielded wire for my cam when I re-wired the car a few years ago. Both being on that ground could be the problem.
 
I am going to try to composite log it tomorrow and see if anything is happening
 
I went back through some of my notebooks this morning from when I re-wired everything. I did run a separate shielded wire for the cam signal. I used pin #17 on the MS3x for the ground. I don’t remember how I came to that conclusion but it would have been based off the manual or a reputable post on the MS forums.

while looking, I did find people saying they ran the cam sensor ground to the MS units sensor ground (pin #9 on the main board) and didn’t have any noise issues.

what are you using for the ignition? Is the stock coil still in place? If so why not run wasted spark? Then you don’t need a cam signal. I ran that way for a number of years before I moved to the COP setup I have now.
 
I just went through with the composite logger and I am still not getting a signal. The retard at diyautotune told me I needed the quadspark and expansion shit to run wasted spark.

I am setup to run the factory coils in a wasted spark setup. I am not trying to do anything weird. I am just trying to get it running with what the car originally had. It is pissing me off and this car needs to go back to its owner. I am sick of working on it.

I took the cam signal ground of and still I am not getting a signal. I absolutely cannot believe this is this hard. It is a stupid three wire sensor. I have followed all the instructions, the 420a instructions and the quadspark instructions. And nothing.

the only thing I have been able to do is turn the stupid fan on.
 
The forums there are a joke. No one has any actual helpful answer. Just read the manual is all they say. And that has done me no good so far
 
The reason for the quad spark is the main board only has one spark output. You can add a circuit for a second one, but the MS3x is the easier way to do that.

so the sensor is getting 12v power, ground is to pin 1 on the main board and signal is to pin 24 on the main board, correct? Just trying to double check things. Diagnosing electrical stuff over the internet is not easy. Have you double checked the wiring into the sensor?
 
I have stripped the wires all the way to the sensor and the colors do not Change or branch off. I do have the stupid resistor for the signal wire jumped off of the 5v source. I have not tried to wire it straight to the exit with no resistor as the 420a megasquirt instructions say to do the pull up resistor.

I have tried both 5v and 12v. In my case it of course is a 3 pin connector.

pin 1, yellow- 12v currently
Pin 2 black/green- ground
Pin 3 blue/white- signal with 1k resistor jumped with 5v

the picture is how I have determined the pin out directly from dsmtuners here. As I said, three wires. Doesn’t seem like it should be this hard.
You must be logged in to view this image or video.
 
I just tested the signal output and they are saying it needs to move from 0v to 5v as I pass the magnet for the sensor over a grounded metal. I used the block with the old sensor and the signal is stuck at 5v no matter what.

I am wondering it the pull up resistor and jumping the output signal off of the 5v reference is my problem.
 
That resistor should go between pins 24 (crank signal) and pin 26 which is the sensor ground. It shouldn’t be getting an additional 5 volts there, it needs a ground.
 
If you remove the resistor, the composite log should show the top image. With the ground in there it will bring it to the bottom image.


You must be logged in to view this image or video.
 
Pin 26 is 5v reference. Pin 7 is sensor ground on the main harness.
 
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