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 good tune almost everywhere else but am having a terrible time getting rid of the stumble when i blip the throttle from idle or from about 1800 cruise. It falls flat on its face. I have changed and rebuilt my msq so many times trying to get another problem fixed that I have no idea what the settings might be to start with for a v8 or if mine are even close. any suggestions?
Also in my log the values were listed as map dot max 1118 min -1563, tpsdot max 952 min -1045
MS2 v3.0 PCB, 2.89 firm, w Scotts Adpt board 2.0a
TunerStudio, LC-1 WB O2.
93' LX 5.0 5spd, Original owner 21k mi. Black on Grey
Turbonetics 62-1, GT40 Heads Port/Polish, Wolverine Cam, 70mm TB
Your TPS settings are close to an on/off switch. Look at the slope of that graph compared to the TPSdot changes you are getting in actual driving. I would look at the range of TPSdot you are seeing under a range of driving conditions and set your threshold just above the TPSdot you see in minor movements of the gas pedal and have your scale go from around that min up to the higher range you are seeing (this will flatten out that TPS slope). Your current value of 40 may be a good spot to start with. I would then flatten out that enrichment graph, start with something closer to a 45% angle out starting at your threshold value (you currently have two points under the threshold) up to the higher end of the TPSdot ranges you are seeing.
The shape of the MAPdot looks okay to me, but like with TPS make sure your threshold is not too high (or low) by looking at the rates of change you get in various driving conditions. Then set you beginning and end points closer to your range you are seeing (currently you have two points under the threshold, so to start tuning I would shift your slope to the right).
Try adjusting your blend of TPS vs MAP for AE. Some find they do better with all TPS and no MAP or the opposite, or a mix.
And don't fall into the trap of seeing a lean spike when it falls flat and thinking you need to keep adding more fuel. A noob friend of mine (cough cough, me) did this and the lean spike was from flooding the engine.
OK where I'm confused is here "Also in my log the values were listed as map dot max 1118 min -1563, tpsdot max 952 min -1045"
Thats what happens when I blip to full throttle for a split second. Should I be looking at cruise only throttle like mapdot 45-300?
So basically the 2 problems I have are cruising lean out stumble, and tipin full throttle bog, if those terms make any sense.
Still confused.
Mike
MS2 v3.0 PCB, 2.89 firm, w Scotts Adpt board 2.0a
TunerStudio, LC-1 WB O2.
93' LX 5.0 5spd, Original owner 21k mi. Black on Grey
Turbonetics 62-1, GT40 Heads Port/Polish, Wolverine Cam, 70mm TB
Thanks for the help. I did get it working alot better by looking up the default values from an old msq then modding to match my injectors.
heres what I have now.
MS2 v3.0 PCB, 2.89 firm, w Scotts Adpt board 2.0a
TunerStudio, LC-1 WB O2.
93' LX 5.0 5spd, Original owner 21k mi. Black on Grey
Turbonetics 62-1, GT40 Heads Port/Polish, Wolverine Cam, 70mm TB