Where are you guys hooking up your megasquirts to receive rpm data from the second gen engines? I tried the black tach output plug on the leading coil harness but didn't get any reading on Megatune. Tried a few of the wires going directly to the coils under the plastic covers, still nothing. I could have a harness issue or something else, and I don't have the megastimulator.

So yeah, where is your tach signal wire hooked up to on your FC?

 

I used the -ve terminal of the leading ignition coil on my old FC. Did you verify operation of your Megasquirt after it was built? If not, bench-test the unit to be sure the tach input, and all other circuits are functioning properly. A stimulator is available that simulates all inputs, provides an artificial tach signal, and has led's for all outputs. Many MS builders have one of these to test new builds or mods.

 

I'm using msns-extra with the wheel decoder, so my tach signal is coming straight from the CAS

 

Either my megasquirt is fucked or it's fucked, I'm about to order a stimulator kit so I can verify that it's fucked. No rpm signal no matter where I put the wire, including the FC dashboard tach signal wire.

 

Trigger signal from CAS. RPM signal going to my tach is from one of the leading coils. It has two pulses per rev which matches a 4 cyl/2 rotor tach.

 

Did you hook it to one of the nuts at the top of the coil, or somewhere on the connector, or the black rpm signal plug? I tried 'em all.

 

First things first, get yourself a Stim....maybe see if another person in the area has one you can borrow?

Second, did you put a jumper between XG1 and XG2?

From the Megasquirt manual:
In the troubleshooting portion:
"1) Verify that you have a XG1 to XG2 jumper in place on the MegaSquirt PCB. MegaSquirt will not receive ignition pulse if this jumper is not there. See assembly step #54 for more details."

Please read step 54 first!

 

One of the nuts.

 

Thanks. I'm sure I have the XG1-XG2 jumper in correctly but I'll review step 54, and I ordered a stimulator kit. I NEED this thing to work, I can't stand my stock ECU any longer!

 

Got it solved, also I got a stim to verify everything with. In a nutshell, the opto isolator U4 was installed backwards. Everything works now, yay!

 

Another tidbit: the black tach signal plug from the leading coil gives a useable signal, as does its negative wire.

 

NICE! Thanks for the info!

U4....I'll have to keep that in mind for the next one I build....just incase.

Did you get your car running yet?

 

What a pos, this project is taking 10x longer than it should. Easytherm is ****, I got the MS working perfectly on the stimulator and in the car with what available signals I had, and wanted to get it to read data from the stock air and water temp sensors so I tried downloading both versions of Easytherm. The newest version won't even start, the older version works but totally wipes out the MSNS_E firmware on the megasquirt in the process. I'm giving up on easytherm and going to experiment with potentiometers on the bias resistor locations to find what value to eventually hard wire in place so my stock sensors read correctly.

Then my ******* laptop got a virus or some **** and now it won't even start megatune. This is almost as bad as blowing a side seal over and over again due to porting mistakes (ask me how I know), and of course I don't have a thinkpad compatible extension CDrom to reload windows 2000 with. Windows is ****, hackers can kiss my *** for ******* up the internet as we know it with the full array of binary demons that have taken over my laptop.

****

 

This is a diy project, but many 100's of people have successfully completed the steps you are now struggling with. There are instructions for using ET with MSnSExtra on the msefi forum, and also included in the readme.txt file included with ET. You might want to try slowing down, dropping the profanities and following those instructions. This step is a 5-minute job at best.

To get decent air temp resolution you'll need to change out the bias resistor for one of much higher resistance. Anything in the 30k to 50k range is fine, but record the value and enter it into ET when generating new tables.

 

I went ahead and bought some potentiometers and soldered them in, then calibrated them with a screwdriver. The laptop issue was some phantom problem and I was able to use megatune today.

Long story short, I got the car to run on the MS, it pulls harder in first and about the same in the other gears, and staged injection is a bit of a mystery. If I set the injection to simultaneous and get it to idle, when I switch to staged it causes it to die. I need to look into how to reset the fuel tables and set the ratio for injector staging, as I think I'm leaning out when I stage the injectors.

Then my laptop battery's 30 min lifespan came to an end and hopefully the car power adapter for it will arrive in the mail soon.

Wow, I can't believe it's actually running. Right away I can say the megasquirt cured my FC's persistent hot start flooding problem; looks like the stock ecu really likes to prime on startup.

Thanks for all the help everyone.

 

Thanks, I'll look into it. I guess I just expected to be able to read the instructions in easytherm's readme and have it work. MSNS_E is the twilight zone or so it seems, sometimes I would disable the spark function and have the firmware crash the next time I tried to power up the unit. I'm not an electrical engineer, I'm a mechanical engineering student. Code, circuits, file placement in proper folders and lots of obscure instructions are just too much for my visual mind to take sometimes.

 

Update: the car is starting and running pretty well, has more torque than before and the gas mileage looks pretty good so far.

I settled on a 15k resistor for the air temp bias resistor and am about to attempt to get easytherm to work with it.

I was able to find the info for the ignition circuit and will try to order some parts for it, but yes I'm kind of pressed for time, engineering school tends to put a squeeze on time and money (taking a summer class while working full time + playing with the car projects).