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Hey guys. Tuning a 19 Durango 5.7 with a Procharger on it. While crusing the truck is running 10-11 AFR. Sometimes in the 12s but in the 10s and 11s during regular driving. The commanded afr is 14.7 and the fuel trims seem like they are way off. While it is running rich we're seeing good fuel trims. At idle the long terms will be maxed out negative but the short terms are maxed out positive just cancelling each other out but idle is the only time it seems to run were it should. Any ideas?
post a tune file and data log. also what injectors are you using?
Sorry for the delay, finally getting back to this one. So here is a quick cruise around the block with this truck. Fuel trims are all over the place and worse...the wideband (sorry it was recorded) was reading 11.9-12.0 pretty much the whole time while cruising. Idle was around 13.5
Wideband works find, just tuned a few other cars with it without issue.
The injectors are FIC 60lbs I believe and after reviewing the data I'm thinking maybe one of them is cutting out and the fuel trims are adding fuel to the rest of the cylinders on the bank? or maybe the o2 is just bad. Something seems imbalanced. I'm also guessing my wideband must be in the ypipe getting a mix between each bank.
I'd be curious to see the injector pulswidth logged for all of the cylinders. Overall, through the entire log bank 2 (ST+LT) is 15 to sometimes 60 or 70% lean. Any chance to monitor fuel pressure on the bank 2 rail?Quote:
Originally Posted by JASON11WS6
Attachment 131352
So here is another quick scan with a new o2 sensor on it. I went wot on this one for a bit to see what it would do....it actually ran lean in the 13s afr.
The rest of the time I was seeing 10s and 11s afr while cruising. The old o2 was pretty black as well so we are seeing true rich conditions even though the ecm is saying lean. It appears to be adding fuel for no reason. Really thought the o2 sensor would have been the issue. The driver side bank seems okay. The passenger bank is running almost twice the injector pw. I believe that is because of the fuel trims staying so high. At wot you'll see the pw is the same on all 8. Any ideas? Really seems like the fuel trims are messing up everything
Turn closed loop off, clear the fuel trims and then see where you really are without 02's messing around with the fueling.
Just put the CL enable temp higher than hot ECT to disable CL.
Hmm… Does your ECU go into open loop when its in WOT? That would explain the bank to bank injector PW coming back to being equal under WOT, your VE tables are identical bank 1 vs bank 2, which is as I would expect. The bank 2 O2 sensor is thinking bank 2 is lean, and during part throttle while in closed loop the ECU is trying to correct by adding fuel to bank 2 by increasing the bank 2 injector PW. Problem is, the bank 2 o2 is not showing any response to indicate there was any success in bringing bank 2 richer. Could u have a horrendous exhaust leak allowing the bank 2 o2 to be getting a constant whiff of fresh air?Quote:
Originally Posted by JASON11WS6
Latly, do you intend to leave Neural Network enabled when dealing with an issue like this? Looks like its enabled in the calibration file you posted earlier.
Attachment 131459
I went closed loop but the long terms are still there. It was better, I was getting 14 afr while cruising but it drops when off throttle back to 10s. I'm going to hook the wideband up to the scanner and turn off the ann. Anyway to turn off the long terms? Also, couldn't reset them either with hp
the way i see it if you make ect 376 degree in close loop enable it is no longer using the trims cuz its not in closed loop so it is not correcting
batt disconnect will reset ltft
i believe writing a calibration does as well
why do you have two intake air temps and why are they 150 degree away from one another?
The ltft will not reset. I flashed the ecm twice now. Updated to a speed density tune again. Seems better but the ltfts are still causing issues. It's a supercharged car so the manifold temps are probably a little higher. I'm guessing one of the other temps isn't reading anything and it's pegged at 32? Just a guess.
Here is a new tune and log. Looks like the long terms do the same thing they have always done and just won't reset.
first of all for part throttle fuel work i dont even hit 'start scanning' until my t-stat opens
that thing wasnt even to 200 yet when you stopped
it did look like it was still correcting - i made 2 changes - check it out
for mine i added stft to the channels and made two more histo's so i am not always looking at the sum
I just need to find a way to shut off these ltfts at this point. I'm going to have to unplug the battery but this guy has a system in the back with to massive batteries that are all covered and hard to get too. Hopefully leaving it unplugged for a while will do the trick.
did you try the 2 adjustments i made?
If a battery unplug isn't an option, and for some reason HP Tuners isn't resetting adaptives from the scanner (you did attempt to reset them from the special functions tab, yes?), then maybe it's time to get a bi-directional scanner involved, or purchase AlfaOBD and an appropriate OBD dongle.Quote:
Originally Posted by JASON11WS6
If the scanner wont clear the LT trims,
just unplug the 2 large PCM connectors for 30 secs,
that will clear the LTFT without upsetting anything else in the vehicle that a battery disconnect might.
Yes, no change on the ltfts. I'm going to try and pull the ecm plugs and see if that does it. I feel like the truck will run fine once the fuel trims are off.
pulled the ecm, it reset the fuel trims. Now I can finally tune this thing