The MegaSquirt Project has experienced explosive growth other the years, with hundreds of new MS installations occurring every week - a phenomenal success! MegaSquirt has been successfully used in all aspects of Internal Combustion engine applications including R&D, Industry, Race, and Research. The MS project has transformed itself from a simple R&D project into a full-featured mature engine control system. To reflect this the support structure has also changed to meet the needs of MegaSquirt Users.
Moving forward, the R&D forums for MegaSquirt project are in a read-only mode - no new forum posts are accepted.
However the forums will remain available for view, they still contain a wealth of information on how MegaSquirt works, how it is installed and used. Feel free to search the forums for information, facts, and overview.While the R&D forum traffic has slowed in recent years, this is not at all a reflection of Megasquirt users, which continue to grow year after year. What has changed is that the method of MegaSquirt support today has rapidly moved to Facebook, this is where the vast majority of interaction is happening now. For those not on Facebook the msextra forums is another place for product support. Finally, for product selection assistance, all of the MegaSquirt vendors are there to help you select a system, along with all of the required pieces to make it complete.
Forum rules Read the manual to see if your question is answered there before posting. Many users will not reply if the answer is already available in the manual.
If your question is about troubleshooting, configuration, or tuning, you MUST include your processor type (MS-I or MS-II) and code version in your post. If your question is about PCB assembly or modifications, you must also include the main board version number (1.01, 2.2 or 3.0). For tuning/troubleshooting questions, please attached a datalog and your MSQ file to your post.
I have a very solid tune, been running the same/similar numbers for almost 4 years.
Recently I have made some changes to my setup, and now my problem lies with cranking. Once in awhile, when cold, it takes quite a few cranks before firing. Now, I can adjust idle valve cranking PW, and/or fuel cranking PW. There is basically no feedback. I can make changes, and try, but once it has cranked a few times, and/or sputtered, or started, then it no longer has any problems starting. The problem only applies to the first start, the first 10 seconds. Since there is essentially no feedback in this situation, how do I know what is going on and what is needed?
Ya, but what is our feedback? EGO? on the first start at -10C? Not only that, lets just go out on a limb for a moment and say that our ego in this situation is accurate and believable (thats a long limb). What O2 reading are we even shooting for? When you combine the low rpm of a crank, the low temperature of the motor, the fuel requirements of the first few revs, the ASE required to stop the motor from stalling... there are far too many variables to consider. Also it's a situation that is purely dynamic, there is nothing stable about it. We are trying to tune a transient between crank and run, almost all the inputs to ms (except maybe the tps) are changing at a very high rate. So what are you looking for in your data logs?
I think really the easiest way to do it would be to find an OEM setup as similar as possible to what we are running, and scope the injector PW on starts, at different temperatures.
Does anyone have any theory or links to any about cranking fuel/timing requirements?
Turn everything OFF except cranking pulses,start at 0.1 and try starting,increase pulsewidths until it fires and you have your cranking pulsewidths at that temperature (and a flat battery)
that sounds helpful. So turn off ASE and WUE? What is 'everything'? and what about the Cranking idle valve PW? surely I cant turn the air valve 'off', the engine wont get any air at all. Any recommended procedures for tuning idle valve? I suppose the more you open it, the more fuel it will need for cranking PW. This is probably why my numbers are off, I changed my idle valve setup completely, so now my cranking PW is all out of whack for the amount of air I am giving it.
