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Anybody else realise that the Pedal Map tuning doesn't work as it should. The only value that seems to have any bearing on the tune is the max mm3 value at 100% Throttle. The rest of the map does absolutely nothing no matter how you set it up.
I've been trying to make the pedal less touchy and quickly realised this map inst doing what it is supposed to. No matter how you map it it seems to be completely linear based on what is in the 100% throttle row.
It's not a gas engine with a throttle. Its a governor based diesel. Think of the gas pedal as an RPM request, and the tables are limits of how agressively it tries to reach that and hold that RPM. You can make the pedal way less touchy by usiung realistic governor max rpm targets, then it wont just jump to full load fuel.
Can you go into more detail on how to make the throttle less touchy?
On my 03 the "part throttle gov" was enabled on my "base" read. Every other 03-05 "stock" file I have looked at this is set to disabled. My 03 is very early production, maybe has something to do with it I'm not sure. All this map does is basically limit the overall mm3 based on rpm and throttle position.
Now most diesels have a throttle map that correlates to a requested mm3 which is then figured out based on the pulse map. This is what I'm used to and normally if you want to remap the throttle its very easy to do. However on this truck the "base fuelling" "pedal" maps don't influence anything based on my testing except the 100% row will limit overall mm3 the rest of the map doesn't do squat, you can fill it in with zeros.
I admit I don't know much about the governor stuff in these computers, can you for lack of a better word "remap" the throttle with these tables? Where do I start? I notice small changes year to year looking at base files but they don't make much sense to me.
You?re fueling goes off of more than just your accelerator pedal, it also uses input from rail pressure, baro, load, exc.
I?m working with the same issue, I?d spin the tires and blow smoke everywhere just from hitting a bump.
I?m trying to make my rail pressure less aggressive and it?s helped the touchy pedal issue a lot.
Also, try going to your rail pressure tables and just smooth them all out.
Rail pressure isn't the issue. In every other diesel I have ever tuned your throttle position translates into a requested amount of fuel. With this truck I think the throttle position translates into a requested rpm, more like a governor then a throttle. So the more you turn up the tune the more aggressive it seems because all it cares about is reaching the desired rpm.
I think this is what Turbo_mike was getting at.
I just don't know how to dial down the sensitivity. I can use the "part throttle gov" map to limit it and build a nice curve but it seem like the incorrect way to solve the issue.
Look at your duration table. It goes off mm3 and rp. If you?re rail pressure map is shit, it?s going to jump from cell to cell drastically as your mm3 changes
Nobody is talking about duration or rail pressure.
I am talking about pedal position translating into requested fuel, which there are maps for that DON'T work as labelled. This I found odd, as with every other diesel I have tuned this is typically how fuel is requested. So I made a post saying "hey these maps don't work" (7731 & 7732). Turbo Mike is the only one who made a valid comment to the point and said the way these trucks work is the throttle input is basically a rpm request.
I've been tuning Diesels for years I understand the role of rail pressure and how the f*****g duration maps works. However this is the first "governor based" diesel I have worked with.
Well, you said you were trying to get rid of the touchy accelerator pedal. Good luck.
I bet you have all your limiters off/maxed, and you have your governor max numbers higher than you woiuld ever actually rev the truck. So because of that, any time it's below desired rpm, it applies max fueling for that rpm, with no limits. Your percent load comes from rpm delta of current rpm request from the gas pedal vs maximum possible rpm, and that's used to look up the value that you think is the part throttle table. So if that function is altered or disabled, then so are those tables.
I think im in the same thing...at 60-70% tps it goes to the max of the table... someone figure it out?
Tried with part throttle governor and it do a very good work