Hey guys, I'm running really rich at idle and on decel from about 2000rpm and down. The A/F is 11.0 and lower. I'm running T-LM_25_MTX_S-IV (the latest version), on my 1987 Shelby Z. I've played with the PE table, and the fuel pressure, but to no avail. The car runs perfect under part and full throttle, and decel above 2000rpm. 2000rpm and lower and it's just drinking gas. Any suggestions?
Subscribed. I can't help you yet, but I'm having the same issue. My AFR isn't quite that rich, but still in the 12's at idle and decel. I'd rather have it on the lean side until I'm in boost anyway. I'm in the mid 14's at steady cruise, and low 11's at 20 p.s.i., so I don't want to mess that up.
You probably need to pull some fuel out of the fuel no throttle table down there. I have to do that also. This is even with a properly tuned pumping table.
Is there actually a graph for fuel no throttle? I see where the AFR settings draws the yellow line on the fuel part throttle and fuel full throttle graphs, but I don't see fuel no throttle anywhere as a graph. As best I understood, changing the AFR values in the settings screen just draws the yellow line on the graphs, but you have to manually adjust the curve. Is that correct? If so, I see no curve for no throttle in the .bin or the .tpl.
Now that I have a netbook to tune with, I did go out and play with the PE graph with the car running. I only messed with the low side of it, but I did get it quite a bit closer. I'm in the high 13's now, and it won't make your eyes water standing behind the car at idle.
There is a table for it. It's been a while since I've used MP tuner, and a while before that since some of the table names have been changed slightly. It's in there. You just need to knock it down some in the lower rpms and you'll be all set.
Dragging the brakes at WOT is the way to set the pumping table though. Once you have that dialed in the rest is pretty easy.
it's under fuel/running/fuelBaselineFromMAP. Lean it out based on vacuum level. Based on looking at the stock 2.5 MTX in T-LM it does look fat rich.
Best way to set the PE table is to disconnect the WG arm to achieve 0 psi, then do a 3rd WOT gear run recording the a/f ratio. Then boost levels don't come into play.
beautiful responses gentlemen! I can't wait to tweak this thing a bit more this evening and report back. Thanks!
Yes, thanks for the tips and info. I think this will fix me up on this portion of my tune. I'm trying to have a fuel-miser in vacuum, and a monster in boost.
The ECU will try to adjust fuel to the switch point of the O2 sensor, If you go beyond 25% beyond that the car won't be able to adjust and it won't run very well. Now if you have an Innovate wideband then that's a different story.
The table only goes to 14.7" vac...my issue is at idle, and decel, which is about 25" vac.Originally Posted by GLHNSLHT2
The table is in psi, -14.7psi is 30" of HG For some reason it won't show the vac in " of hg on t-lm. But if you scroll the mouse pointer over it it reads in "ofHG.
Ohhhhhhh I'm a dummy...makes a bit more sense now! Thanks again!!
Ok, I ran with the car with the wastegate disconnected today. 10.3 AFR at WOT in 3rd, and 10.2 slightly dragging the brake. Just so I'm clear, am I shooting for my ideal AFR under boost here, or am I about to crank this thing back to stoich here?
What you want is a steady a/f ratio and a steady boost level. That's why I say disconnect the WG as that usually allows WOT and a nice 0psi from 1000rpms to redline. If your a/f is all over the place on a full throttle run through 3rd gear you need to adjust the Pumping Efficiency table to get rid of the bumps and dips of the a/f as you go through the rpm range. Once that is dealt with then you can start tuning the fuel for vacuum and boost.
at 0psi at WOT maybe 13:1? I don't think Stoich would be a good idea.
I would drag the brakes to keep the car at a set RPM for up to 1min so that you can make your readings when everything is under a steady state of load. I start at about 1500RPM and go up 500rpm at a time. In so doing I get the pumping table dialed in quickly and accurately.
I would agree that 13:1 or so would be a good place to be. I usually have it set so that it's about 13.5:1 as it's coming into boost and dropping down to 11.0 or 11.5:1 while above about 5PSI.
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