2014 V6 mustang procharger stumbles/sling shots at 2.5k rpm
I'm totally lost on this one. I'll post up a log and tune file - need help sorting out this one drivability issue. The car drives fine everywhere else. I tested the heck out of this across RPMs and gears. Turned off traction control just to verify that wasn't a factor for a bit. Doesn't matter.
If I roll the throttle gently at 2k rpms so that it hits WOT a bit softer at 2.5k it will power thru it. If I Jam into it the car hits a wall, RPMS flutter all over and then it sling shots forward off that once things stabilize.
Spark plugs are brand new one range cooler - gapped and installed just yesterday. Again it drives fine 90% of the time but I do hit this condition pretty regularly getting into traffic and it's obnoxious having to remember to roll the throttle. I'm open to it being a mechanical issue as well...
Do I need to add any PIDS to help find this issue? I don't know enough yet to set up a histogram to track it... thanks in advance.
torque = (moment of inertia)(angular acceleration)
If I had to guess lowering this made the ecu think the engine should rev up faster than it is. With the added load of the procharger I don't think this is so. May have something to do with your problem.
I did a compare on the file to my stock file. The engine inertia torque is unchanged at .015. Tho I think that was a great idea to check - the idea had merit. I checked all my IPC sums and demanded torque values to make sure they didn't conflict. I.e. having a driver demand higher than a torque management limit. Everything looks good there. Any other ideas?
Bump - still having issue. Can't think of anything more to tweak in the tune to fix this. I'm including a screen grab of a spot that really concerns me in a log file I ran just before the previous one but I've seen this pattern in all of the logs. I also have the worst idle hunt. Tweaking idle air flow down or up hasn't helped it at all. So I'm cleaning the maf sensor at the moment.
basically the car goes quite lean - like it is missing - for a brief split and then picks up again and accelerates on from 3k rpms. but it only does it at this range in 2nd or 3rd gear. in 4th+ it rolls thru no problem.
Wheres your BOV in relation to MAF, throttle body, and head unit? If you have a BOV venting to atmosphere after your MAF this can cause these issues when you let off the gas or slam the throttle shut. You may just have a malfunctioning BOV or BPV I would check the lines for kinks, rubbing, and leaks. use and air compressor and regulator and make sure your valve is working properly.
BPv is a brand new Turbosmart recircle. Plumbed in at the compressor outlet and enters side of intake tube about halfway between blower and filter. MAF is after the intercooler. Car holds 8psi of boost no problems. tested with a leak tester from a reputable shop... attached to snout of blower and ran it up.... I've also leak tested the whole system and it went to 5psi before the oil dip stick started venting. Which is when I called that quits since you're not supposed to pressurize the block. My MAF transfer is beautiful - between 1 & 3 percent off all day long at max on Long term and the upper RPMS are within 3% on short term.
It looks like you are having the RPM drop when your load is climbing and the transition from fuel economy to drivability is not occurring fast enough. Other have found drivability improvement from lowering the fuel economy max load and the drivability min load. This should help speed up the transition to the more optimal mode.
Can you specify which tabs those are under? I also dialed out Tip-in and such under Torque management. If I'm already in borderline spark, it doesn't have any glitch. but if the car is in base or as you say, fuel economy and I dump it into borderline real quick at 2500 it hits tip-in detonation and all this nonsense.
Been Busy tho here's a brief update. When I reduced the load limits as discussed above it made the part throttle delivery extremely choppy. The spark torque limit stuff I want to play with a bit more but it doesn't seem to effect this specific problem and the load limits didn't either and just made the car surge so that maintaining speed was extremely difficult. It would want to pull a couple mph, then chill out. then pull a couple more. Is there a better way to update those charts so that the limits are moved without it bouncing in & out of Optimum power so spastically. basically it looked like it was fluttering between fuel economy, torque control and optimum power way too much.
On a hunch I changed Idle Interger time underspeed back to 2.0 vs the 1.5 suggested. This lead to an interesting correlation between two issues I'm having. Both seem to be driver demand/IPC at the root cause... how do I smooth out the "Torque N" areas of this log so that it idles smooth with less IPC error? Will applying said fix to other areas of the tune reduce the tip-in detonation call at 2500 rpms?
Here's another log showing the mapped points and such. Same basic issue - goes into Target N, torque control and just wanders around awhile. Then mellows out and goes back into Driver demand. Usually see some tipin detonation at the start of the pattern as well.
The tuning method I have been following didn't touch on that. I agree it's the only place I haven't sorted and will look at updating those tables for the new power tonight.
My mind is mush after an hour reading everything I can find on the torque and inverse torque - just feeling frustrated that I'm so close and while I appreciate the help so far from you guys - I can not find anyone reasonably local to walk me thru this stuff on a dyno. They only want to do Coyote and ecoboost. Haven't gotten the time of day lately. I really was hoping that there was some clear path to build a test and tweak scheme like when I converted the Coyote MAF transfer and Spark OP programs to the 3.7l strategy. First off, I think I'm missing a PID... indicated torque doesn't appear on my list. I have 3.0 and repolled the scanner a while back. Based on the threads I've explored that one seems critical to get a handle on sorting the Torque management. How does one get that over to the support team for HP tuners?
Still plugging away but really need some clear inspiration on getting these mapped points figured out. THanks for any ideas!
Let me expound on the issue - the original file was a diablo sport tune that was cooked up by Procharger as a base tune but wouldn't run - MAF transfer and IPC were way off. They weren't helpful so here I am making the most of the file I've got and it didn't touch the indicated torque or inverse. Just tweaked spark, MAF and fuel injectors. Upped a few things here and there. otherwise it was pretty rough.
For grins while I wait patiently for support to look into the missing PID, here's just a practice version of setting up indicated torque and inverse. Is this going the right way? Do I need to scale the inverse to be similar in torque as the indicated? The numbers are all guesses since I have no means of figuring them out yet. Looking for input on the method being correct.
Stock is on the right and the practice is on the left.
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