Noticed that the car seems to be "holding back" power for a moment or two when I downshift back into 1st gear then it picks right up. It didn't do this before the tune. Is there torque management that I shouldn't have touched? Any other ideas? Dirty Maf?
Edit: 4T65
Last edited by Dusty05; 04-01-2013 at 01:19 PM.
What vehicle? There are a couple out there (4.3 & V8 trucks) that I've seen go nuts if you zero:ENGINE= Spark Retard vs. Torque Reduction and/or Torque Loss% vs. Spark Retard. Without a tune posted I will assume one of those Regals or a car with the same V6 PCM layout. In those cars however, you should be fine eliminating any and all torque or abuse settings. Review your shiftpoints again if you have made changes to them, but especially the MPH upshift and downshift thresholds. Double check to make sure that you don't have two contradicting values confusing the tranny. (An upshift speed set lower than a downshift speed in even just one cell)
AH sorry about that. I meant 4T65. It's on a 2001 Lesabre. I'm starting to think its a transmission issue.Originally Posted by Dr. Nopps
I can post the tune if you want to take a look!
Last edited by Dusty05; 04-01-2013 at 01:20 PM.
Sorry to take forever to get back but.... sure. Post the tune you had trouble with, not your stock one. I'm a little familiar with that layout, and will give it a quick glance. You can zero your TM & Abuse with that operating system no problem. At least I've been fine so far! Like I said take a close look at those shift points for anything that doesn't look right.
Last edited by Dr. Nopps; 04-16-2013 at 01:07 AM.
No prob, I'll post it up tonight. I noticed I had some management removed but not all of it. I wrote another tune with it all removed but haven't put it on the car yet. I'll post up the one that feels funky on downshifts. Like it said, it might be a trans problem too. I don't have much faith in the non-hd's
Here it is. Still has a lull of power then a power burst on a 3->1 kickdown after I turned most of the TM off. I also noticed this thing is full of WOT knock with stock timing and premium fuel.
What worked for me may not work for everyone but.... I always warn people of believe it or not, over-fueling. Especially with these V-6's! Just like you, I had fresh *93 Mobil fuel, stock timing tables, and got knock! So I went into my: O/L AFR vs. Coolant Temp. table and zeroed cells for 50 or 68 degrees and above. Next to that is: AFR Adder vs. Cyl. Airmass, which I changed only values showing richer than 13-1 to exactly 13.0-1. In Power Enrich I changed: Fuel Adder vs. RPM vs. Time, entering a (AFR adder) value of 0.200 to the horizontal 0.0 and 1.6 second row, so you won't slam to 13-1 too quickly and possibly overshoot. I set Base AFR vs. ECT for 13-1 after 68 degrees was reached. Under AccelEnrich I set WOT Disable to: Enabled. This enables the feature that prevents Acceleration Enrichment while you are in WOT/PE Mode. While in WOT/PE Mode you don't want to go richer than 13-1, and that's exactly what AccelEnrich will do. I've used any TPS greater than 33% to enable PE just fine, and would then zero any Delay vs. TPS for my chosen TPS% and higher. I set all my Traction Control AFR's to 13.2 to 1 & zeroed the InjDisable columns. Finally: I maxed the CAT Overtemp Protection activation value and just to be safe, I entered 13-1 AFR for every cell above 762lb/hr, and 14.7-1 for every cell below 762lb/hr in the COT/AFR table. Not only did that little recipe eliminate all the knock I was experiencing, I was able to add a substantial amount of timing before knock would obviously resurface if advanced too far. With the factory high octane table as a starting point, I was able to add around 8 degrees of timing to cells above idle speeds using *93 Mobil. Another 10 degrees could be added on top of that if *100RaceGas was used from Delta Sonic but for $8.oo a gallon at the time.... Anyway, yeah that knock might be it. I couldn't see anything obviously wrong with the shift points so it could just be pulling timing on you. (KR) Also make absolutely sure that when you downshift into 1st gear, you're not physically revving the engine to an RPM that would exceed the values set in your: Full Throttle Shift RPM tables for Normal, Perf, and Hot. If so, raise them. Mine are all set to 5,900 RPM's. I would definitely zero out your Spark Advance: AFR Correction table if I were you. I've never used that table to add timing, in fact I would most likely only use it to subtract timing if anything. Hope all or some of this helps. (Somebody) Good Luck!
01 Malibu A-T 3.1L 93Rev..hpt
Last edited by Dr. Nopps; 04-19-2013 at 06:21 AM.
Thanks for the info! I'll let you know what helps! lol I was wondering if I was overfueling also. I should probably get a wideband on this thing if I'm going to continue to play.
I know everyone is going to chastise me for saying so, but even without a W.B. you should safe for at least the time being. Don't get me wrong, using one correctly will definitely give you a lot of experience and bring you up an entire level as far as serious tuning and ones abilities. But the PCM's factory tables appear to have been tuned to shoot for AFR's well within the range of 13-1 with their setup, so unless you have modified the intake or exhaust enough to effect airflow, or installed a turbo or something, you might actually be O.K. without the wideband until you decide to get crazy.
You said O/L AFR vs. Coolant Temp. table and zeroed cells for 50 or 68 degrees and above. I'm showing a/f ratios in this table, so you mean 14.7:1?
Sorry, I forgot that on some of those engines (like yours) those two tables are setup inverse from mine and your AFR Adder isn't even really used. If you look at my tune you'll see what I mean. I wouldn't just go and change yours to look like that, it's just how they did it on mine. If you changed the O/L AFR Coolant table yourself to mostly 15.5 for MPG's, I don't know. I would at least take the time and try to re-tune the cruising via the narrow bands, if you want 15.5 that badly and won't modify the exhaust or intake on that vehicle for a while. There's another cool way to gain a bunch more tuning experience. I was just sharing my basic experience and concern with going too rich at WOT, you'll have to figure out how lean you can cruise, how to effectively dial that in, and then help me with that one day when I decide to super max my MPG's.
Your idea worked! All knock was gone! I even got to add a degree or two at wot.
Last edited by Dusty05; 05-05-2013 at 10:37 AM.
That downshift lull is still there, but I'm just happy that knock is gone! lol
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