MSefi.com read only forum (Jan.15,2018)

What is the logic one applies in deciding what percentage of accel enrichment to be TPS and MAP based? Mine came with the default set at 100% TPS. Is there a reason to change this, and what would it be? How does this effect driving or economy?

Thanks, Sam

After reading the MEga Manual section on enrichment settings, I noticed that my threshold setting for the TPS accel enrichment was 200%. And the proportion of TPS/MAP was 100%, which if I understand this, means the MAP accel function is not used at all, since the TPS would never go over 100% in its actual travel. This seemed as if this combination of settings would disable that function entirely. So, I set this TPS threshold value at 20, and all of a sudden the idle injection open time went from 3 ms to 10 ms. Why did this setting change the value of the idle fueling? I thought it would do nothing until I touched the throttle, and then kick in. But apparently it does effected the fueling with a static TPS reading as well. Can anyone explain this. The default setting shown in the MEga manual is 20, so I thought that would be safe.

As soon as I changed the threshold setting back to 200, the idle fell back to normal and it idled back qt 3 ms. Then I set the TPS/MAP proportion to 80%, which gave me some accel enrichment. This was enough to make it take the throttle more gracefully. But, I am confused about how to proceed tuning the accel wizard. Any help would be appreciated.

Sam

Sam,

The thresholds are TPS% per second. So if yo go from 0% to 100% in 1/4 of a second, that's 400%/sec.

Setting the threshold to 20% means you are always triggering accel enrichment, which is why your pulse widths jumped. This is covered in the manual.

Lance.

Thanks Lance. We all appreciate your help here! And, thanks for moving this to the right section of the forum. I'm sure by now there is so much written and documented in the manual, every question could receive the reply, "this is covered in the manual". It is a fabulous resource. People have put enormous time and talent into its writing. The Manual is one reason I decided to move back to Mega Squirt after two years of fooling with another comercial product. The manual is standard bed time reading for me these days. But, I am sure you are tired too, of answering the same questions over and over. Hang in there please.

It makes me feel stupid to ask questions here on the forum because of this.The answer is almost always, "it is in the manual". I have not wrapped my mind around the organizational logic of the manual yet. The challenge is that the manual has grown so over the years it is really difficult to find the information you need at the moment. Most of my questions arise after I have read and re-read the section of the manual I am in, and still don't understand a particular thing.. At that point, I am either too thick headed to get it, or I feel the answer is elsewhere in the manual, but don't know if this was covered in more detail earlier, and is now information I should be carrying with me, or if I must move on to find more detailed information. Either option makes me feel stupid, and reluctant to ask. But, I do anyway. So, thanks again.

Sam

This might explain the number of stupid questions, and apologies ahead of time for asking them.

Likely this subject is covered in the manual too. If there is a section on how to find things, could you give me a link to that.

Sam,

The manual is huge, and it can be intimidating (or just a chore!). We have added a search function for the manual (near the middle of the top of the forum page). So you can search for 'TPSdot threshold' and narrow the volume you have to look through (then I use 'ctrl-F') to search within a page with Firefox.

The TPSdot has changed over the years. There was a change in V1.3 code (to % from volts), and then a 10x adjustment in the scaling of TPSdot was made for the 2.8 code (more here: viewtopic.php?f=31&t=38811&p=231128&hil ... ot#p231121). So the manual's illustrations don't, and can't, apply to all situations.

In general, the manual has specific sections relating to specific code, for example, all the parameters for the 2.8 code are here: http://www.megamanual.com/mt28.htm. The more general explanations are linked from the manual table of contents: http://www.megamanual.com/mtabcon.htm - and it's worth scrolling through that just to see what is there, for example the acceleration enrichments section is here: http://www.megamanual.com/ms2/tune.htm#accel

Lance.