I am putting megasquirt on a s5 n/a. its a 3.0 board running MS w/extra 2.0.1 .
I followed the pdf guide in the stickied ms2 post in this forum.

Right now I am only testing to make sure I am getting a correct signal from the CAS, so I have not hooked any other sensors up, except the CAS. I get an rpm in the range of 210-220 rpm, but about every 1-1.5 seconds the rpms drop to zero and megatune indicates that it lost sync. Immediately after it loses sync, it syncs back up and returns to the 210-220 rpm, and the cycle continues. I have added a 0.1uF capacitor on G+ to ground to help with the noise with no luck. I also tried tuning the potentiometers also with no luck. If anyone has any input on why it is doing this, please post.

 

You don't want a .1 uF cap, you want a .01uF Cap, but that's probably not the problem.

Are you using an lm1815 to condition the G signal? You need to ground pin 14 on that.

Finally, you should use the 2.1.0 firmware or later. 2.0.1 had some rotary specific bugs that will cause you problems even after you get the RPM signal stable.

Ken

 

yes i am using the lm1815 to condition the G signal. I did ground pin 14 straight to ground, but it goes through a .01 uF cap like the diagram in the pdf says. I added an additional .1uF cap from G+ to ground, but it did not change the results i posted above. I will change the firmware and post back with the results.

 

The pdf is wrong, please use a .01 uF cap (103). Thinking about it for a second, it could be causing the 2nd trigger signal to occasionally drop out.

Ken

 

I have updated to 2.1.0 and re-read the assembly guide to fix a few things on my board. Also took out the .1uF cap. It is now syncing correctly. My next problem is that the fuel injectors are not firing. I tested the voltage across the fuel injector leads and both read +12v. I tested the voltage across the injector output from megasquirt(which should ground out the injector) is reading a constant 0v, which means megasquirt is not grounding out the injectors to fire them. I have tried a few versions of code with no luck. If you have any suggestions on what could be wrong please post.

 

That is probably a wiring issue. Have you tried using test mode?

Ken

 

I just tried the test mode, but it did not fire the injectors.

edit:

I also tapped a ground on the injector output on megasquirt and it fired the injector, so it cant be the wiring.

 

Did you build your own MS? Did you get a stim?

Ken

 

yes i built my own MS. I do have a stim, but I thought that since I have a VR sensor setup, that the stim would not replicate a VR sensor output.

 

Well if you use the EDIS setting in Megatune or TS and switch to that setting on the Jimstim you should be able to get rpm to test the injector circuit on the board.

 

Yeah, you only need to set it up enough to get the injector LEDs to blink.

Ken

 

I have the MegaStim. I changed from toothed wheel to EDIS and got an rpm on the stim. The led for I1 was blinking, but when I put the rpm over 3500 (where my staged injection should start injecting the second set of injectors) I2 did not blink, nor did it blink anywhere. I switched the leds from I1 and I2 to make sure the led on I2 was not blown, but it did the same thing as above. Since I am running an '91 S5 N/A I have high impedance injectors. Because of this, I removed the PMW flyback circuit for the injectors, but MS is still not firing the injectors. I am guessing that some part of the fuel injector circuit is blown, so I am going to try start replacing all of the components for the fuel injector circuit. I am at a loss of what else to do.

 

Maybe post your msq and we can check to see if maybe the configuration is setup wrong or see if you missed something. It happens to most of us here.

 

Sorry, I guess I should have posted this sooner.

 

I noticed you have your Bank 2 injector characteristics set to off. Try turning this on and set this to what you have for Bank 1 and see if it activates.

 

I changed the Bank 2 injectors to on and set the settings to the same as Bank 1, also put the rpm above 3500 where they should come, but the I2 led did not come on.

 

It seems then there is a problem with the Inj circuit Bank 2. I would start with checking the signal at output of the IXD1404P chip and use an led with resistor (there's an explanation on the troubleshooting page on the megamanual website on how to make one) or use an led from the jimstim and probe pin 5 of the IXD1404P chip. That's channel 2 for the injectors.

 

ok i got the car running, just have to tune it. I replaced U4. I also got a diagram of the fuel injector circuit and started tracing problems. I had some bad solder joints
.

Anyway, thank you muythaibxr and a_reyes1014 for all your help. Also Aaron Cake for your awsome write up. Can't wait start tuning it.

~cr4ckills