rfuerst911sc,
In my firmware development days, we always used a Null Modem adapter which reverses the RTS(Ready to Send) and CTS(Clear to Send) leads and the TD(Transmit Data) adn RD(Receive Data) leads when communicating via a direct link.
Talk to your contacts for MegaSquirt and find out if your system requires a Null Modem configuration or straight through(pin for pin) setup.

I bet it's null as well, I would hope that Megasquirt supplied that cable with the software however.

The cable was NOT supplied I just went out and bought one. After doing research I found out that a "straight thru' was the type I needed and as luck would have it that's what I purchased. I just installed the USB to DB9 cable software and tried to communicate with the ECU. Instead of a "can't communicate" error message I got a "no response' message. I find this encouraging as I believe I corrupted the firmware in the ECU with past attempts of communication. Tomorrow I will work with the gent I purchased this kit from to reburn the firmware with the stimulator and take it from there. I'm feeling better.

They don't really supply anything as a kit. Megasquirt goes through a few approved vendors but all you buy is the kit and free links to info on assembly, install, and configuration. Their forums are a great place to get more info on fuel and spark maps. I think that you can buy the correct db9 cable from their vendors.

edit: Just saw your above post about the cord. Glad to see you are making progress. It took me a long time to get mine working so don't think that you are the only one that this happens to.

Chuck

If your DB9 cable and laptop worked before then unless you changed something, it should still work. I'd suggest you try and think back to what you changed around the time it stopped working.
The stimulator should tell you a lot. Just be sure to use a fresh battery. It will take the relay board out of the picture and you should be able to connect to the ECU with your laptop. If it still doesn't work, either you've somehow damaged the ECU by applying power to the wrong leads from the relay board, or you've changed something on the laptop during your trouble shooting.
Lets assume you hook up the stimulator and Megatune on your laptop connects to the MSII ECU. You can turn the knobs on the stimulator to make it send simulated signals for the various sensors. The RPMs is controlled by two knobs. The O2 sensor won't give you the full 0 to 5 volt range used by a wide band O2 sensor, but if you're using a narrow band sensor that's less of an issue. It will be hard to input a "realistic" combination of sensors inputs, it's difficult to manually produce enough vacuum on the MAP sensor. The main thing you're trying to do is make sure the ECU is reacting to each of the sensor inputs.
Assuming that all checks out, the next thing to do is verify that the connector that connects the ECU to the relay board is supplying 12 volts on the correct pin, also make sure the pins that supply the grounds are giving you a good ground connection. You may also want to double check that all the wires connecting the relay board are connected correctly. The installation guide on the MSII site documents the pins on the connector and you'll be able to see what should be on each pin on the connector.
I'll be interested in hearing what you find out.
Once you get past all these connection issues, configuring MSII to reliably run your engine is not a trivial matter. You need to make sure you're getting a good tach signal. I'm running a Tbitz kit and Tony uses a resistor on the connection to the distributor with stock ignition. I'm hoping you're at least starting out letting MSII only manage the fuel injection.
I'm on vacation all next week and will probably not have Internet access, I'll check this post when I get back and see where you are.

Good Luck!

-Mac

Well today I learned how to use the stimulator. After loading firmware I was able to get a sucessful communication test!!! But when I went to burn the software load I got a "can't execute to controller" error message. But because of the sucessful communication test I now know my laptop and DB9 port/cable are working properly. I'm thinking there is something not quite right in the software.............I'm much closer than I was yesterday. Stay tuned ( pun intended ).

UPDATE- actually had the car running today!!! It ran like crap but it ran. It was running way too rich and I don't think I have a good tach signal which is a major player in this running correctly. My hat goes off to Will R who spent 6 1/2 hours of his vacation time in Orlando helping me with this setup, a finer Pelican member you will not meet. We confirmed I can communicate with my laptop to the ECU via the DB9 port and the USB port. Also confirmed all my wiring is correct as we were getting accurate readings from all the sensors/gauges and wideband controller. I need to work on getting a good tach signal and then go from there. I see a light at the end of the tunnel. I will keep updating this post until hopefully she runs clean. Thanks to all that gave suggestions I really appreciate the help.

GREAT NEWS! I am glad you stuck it out. Do you need a known working fuel map? Let me know and i can send one. Hats off to Will, that is just way cool!

please keep this thread updated as we are watching ;)

Great news! Great thread BTW, keep the data coming!

Rfuerst....if you don't already have one, I'd strongly recomment a PLX Devices wide band O2 controller. You can connect this to the MS and use the auto tune feature :) You can pick these up for 300 bucks and you can mount in your car and monitor the display for the A/F ratio as you actuall drive and tune accordingly.

Yahh!!!!

I do have a PLX model 250 wideband controller. It was trying to make 65% changes yesterday as my air fuel ratio was 11.00 to 1...........WAY RICH!!! I am running a map from a well sorted 2.7 motor but that motor is running higher compression and hotter cams, I thought that map would get me close what do you guys think? bb80sc I wouldn't mind seeing that fuel map, what car and engine config is it from? My email is: sc91183@earthlink.net

Congratulations!! It's definitely been a long road.

UPDATE- Today I received a Tbitz tach adapter and I now have a solid tach signal another problem solved. The car starts right up and idles O.K. but my fuel map or something is not right it's still running rich. I'm getting a air fuel ratio reading of about 11.5 to 1 after idleing for about 15 minutes and I'm still in cold enrichment mode but I know it's just a matter of tuning now. BB80SC I sent you a PM I'd like to take you up on your offer of sharing your fuel map. I'm getting close here guys.

Right on! Congratulations.


Wil needs a medal, that was an extremely generous gesture!

John

That's awesome news. Do you have your tach working also?

Will the tach is working. I started the car again and it sounds better I may have to get some fresh gas in the tank as she has been sitting since Dec. 23rd and it only has about 1/8 of a tank. I have to get a good vacuum source for my power brake booster and I'm ready for some short road trips and some tuning. Thanks to everyone that was willing to help, especially Will for taking time out of his vacation to help me. This is a awsome forum.

I noticed yesterday when I had it running later in the afternoon the fuel pressure was about 48-50 lbs. I have a fuel pressure gauge mounted on the left fuel rail and I'm running 30 lb. hr. injectors and I have a adjustable fuel pressure regulator mounted on the back of the right fuel rail, should I lower the pressure? I was given a "ballpark" figure of about 40-45 lbs. any suggestions on a pressure setting?

What do your AFR and injector duty cycles look like? If you AFR is in target range and your duty cycles is ~80-85% then you are good. If you are too rich when your WOT and cycle is at 85% then you can lower pressure...