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Which function do I have to work with for the commanded af ratio? Also how do you convert the efilive to af ratio?
I tune on a dynapack so when I hold steady state at 3000 rpm at low load it reads ok but then starts to get excessively rich. Like 10.0. But I messed with open loop Vve table and it seemed to get better.
Thanks for the help with the Maf. I'm gonna try it. Customer wants to run about 1 bar of boost. I'm currently working with the 3 bar map. Am I on the right track?
The car does run a heck of a lot better than before. Oh also is there a writeup on how to deal with power enrichment? Still don't understand how that works. Is it similar to accel pumps on other standalones?
Commanded fuel: look at B0141-B0148.
Also look at PE: B3618 and B3670.
In the tunetool, go Edit-Properties->Display and look at Commanded fuel values... you can set this to AFR, but I strongly recommend setting it to EQR...!!!
[ use a cheat sheet to convert from EQR to AFR for your fuel types ]
Also, from your wideband use Lambda instead of AFR.
Power Enrichment:
- enables when the enablers are met, see B0156-B0170.
- commanded AFR (or rather commanded EQR) comes from B3618 and B3670.
- when the enablers trigger, tables B3618 becomes active, and if it is the richest of the active tables then it commands the EQR.
For example, when throttle is opened, ECM goes to OL (B0141,3 become active) and PE enables (B3618 becomes active)... the richest active table (at the operating point) is what the ECM selects for commanding EQR.
BTW: need to start thinking in EQR and Lambda rather than AFR:
EQR = 1/Lambda = AFRstoich/AFR or Lambda = 1/EQR = AFR/stoichAFR
This will make things more accurate and easier in the long run.
I have noticed that when i log data and look at my tune tool the map/kpa doesnt seem to go above 105 even though i know im making boost above that. When i hit that 105 ceiling and try to hold boost above that the car bucks and farts. I forgot to ask which table I would be modding if I set it to maf tune only? i think you said b8024 and b8025 for maf. Would a good setting be B8024 at 3500rpm and B8025 at 3400 rpm?
If you want MAF only, try setting B8024 to 400 rpm and B8025 to 380 rpm... or something similar.
If MAP doesn't go above 105 kPa, then check:
- 3-bar MAP sensor is installed,
- tables B2101, B2103 contain suitable scaling values;
the tunetool suggests values for B2101/3;
sanity check: with key on engine off, MAP should show barometric pressure in your locale (e.g. 100 kPa at sea-level).
hey joecar i checked b2101 and 2103 and it said
map sensor scaler = 94.4297
map sensor offset = 10.34
Used to scale the MAP sensor voltage output into a kPa/psi value.
1bar sensors are typically - 94.429688
2bar sensors are typically - 188.000
should I change the scaler to 188 and tune the 2 bar table? Would that work?
If you have the 2-bar sensor then yes.
If you have the 3-bar sensor then use 282 (i.e. 3*94)... will it allow you to enter 282...?
When the scaler is correct, then at koeo MAP will read the same as baro.
Where is the 2 bar map sensor usually installed? Is there a generic one already built into the stock harness? Sorry for the stupid questions but i didnt build this car. I know that the turbo kit is from hahn and everything looks installed well. If i input those settings to run maf only ie 8024 and 8025 at 380 and 400, which table would i use to tune the maf table?
The 2-bar or 3-bar MAP sensor completely replaces the 1-bar sensor.