vonrottes Posted February 12, 2019 Report Share Posted February 12, 2019 Ask around on other places and only got 4l60e memes... 2000 LS 2wd 4l60e installed a HD2 shift kit following instructions for street/performance while it was apart I also put in a trans-go separator plate to fix the check ball. Followed instruction for V8 applications. Now here is the weird issue... sometimes when it kicks down under hard acceleration, or if I rev the engine in park or neutral it will start shifting REALLY hard 1-2 feels axle hop and the 3-4 is really hard, off throttle up shift only. as well as shifting from park and reverse. it does not affect the shift points, or TCC. if I manually downshift before hitting the throttle it's just fine. The only way to get it to start shifting normal again is the kill the engine with it in park and restart... restarting in neutral works sometimes but not always. as far as the tune goes, I've dropped shift pressures, increased shift times, turned torque management back on and lowered the pressure modifiers.. Also seems to happen more often when it's cold outside. Quote Link to comment Share on other sites More sharing options...
xlr8tn Posted February 13, 2019 Report Share Posted February 13, 2019 No code I'm guessing? I forget off the top of my head which code mine threw that commanded max line pressure.....solenoid code I believe but that's been 10 years ago so my memory is beyond foggy. MAF or speed density and if MAF is it healthy? Maybe it's a load calculation deal causing it? Quote Link to comment Share on other sites More sharing options...
vonrottes Posted February 13, 2019 Author Report Share Posted February 13, 2019 Nope, no code. I'll double check to make sure I have all the diagnostic codes enabled in the tune. It is still a MAF tune and from what I can tell the MAF is ok, doesn't really have any other issues other than this. Not sure what the load calculation would be. Quote Link to comment Share on other sites More sharing options...
Cordell Posted February 13, 2019 Report Share Posted February 13, 2019 Log calculated load and commanded line pressure when it acts up. If the numbers look good you’ll know it’s in the trans. Kind of sounds like the accumulator sticking or leaking to me, but chances are good you’ll need to get into the trans. Quote Link to comment Share on other sites More sharing options...
vonrottes Posted February 13, 2019 Author Report Share Posted February 13, 2019 Cool, I'll do that this weekend. Hopefully it's something simple. Since I just did the hd2, separator and a sonnax accumulator Quote Link to comment Share on other sites More sharing options...
vonrottes Posted February 24, 2019 Author Report Share Posted February 24, 2019 Okay, Finally got it to do it while logging.. When it happens the force current motor shuts off. 0 Ma. Quote Link to comment Share on other sites More sharing options...
Cordell Posted February 24, 2019 Report Share Posted February 24, 2019 Sounds like you missed something in your tune or a sensor is dropping out. In other words if something like a MAF sensor or MAP sensor drops out for some reason (pinched wire, bad sensor, ect) the ECM will think there is no load, hence the trans slips because the pressure is load based. Or you have missed something in your tune and the load calculation is not accurate, or you messed up a trans table. Did you log engine load? Quote Link to comment Share on other sites More sharing options...
vonrottes Posted February 24, 2019 Author Report Share Posted February 24, 2019 I sure did. it happened at the 2-3 shift. load was at 74% current was .23 shift happened RPM dropped from 4,400 to 3,100, engine load dropped to 59% current dropped to 0.08 after about 3 seconds it dropped to 0.00 MAF went from 23 lb/min to 16.67 and MAP went from 85kpa to 92kpa TPS steady at 57% trans temp was to 100F I can upload both the log and tune file if that would be more help. Quote Link to comment Share on other sites More sharing options...
Cordell Posted February 24, 2019 Report Share Posted February 24, 2019 I sure did. it happened at the 2-3 shift. load was at 74% current was .23 shift happened RPM dropped from 4,400 to 3,100, engine load dropped to 59% current dropped to 0.08 after about 3 seconds it dropped to 0.00 MAF went from 23 lb/min to 16.67 and MAP went from 85kpa to 92kpa TPS steady at 57% trans temp was to 100F I can upload both the log and tune file if that would be more help. ...it did that with the throttle steady? Looks like something created a vacuum leak. It’s interesting how the MAF shows less air consumption, and the MAP shows a drop in vacuum. Maintaining steady throttle shouldn’t cause a change in the MAF much at all, and 92kpa is almost no vacuum in the manifold (something I wouldn’t expected outside of WOT). Not positive what exactly you have going on but I’d start by ruling out a vacuum leak. Outside of the obvious intake gaskets and such, don’t forget about everything else hooked to the intake, EVAP components that may or may not be hooked up, the brake booster, HVAC controls, ect. Then I suppose I may verify my MAP reading with a vacuum gauge. What are the MAP readings at idle? I would expect a stock camshaft to be in the 30-40kpa area, my cammed Camaro is only around 55-60kpa for reference. If it’s normal at idle maybe something happens while cruising, maybe it’s not a vacuum leak, maybe it’s all fucked up. Not sure how much I can accomplish over the internet with you I don’t normally work that way. Hopefully my thoughts help you, good luck. Quote Link to comment Share on other sites More sharing options...
vonrottes Posted February 24, 2019 Author Report Share Posted February 24, 2019 ...it did that with the throttle steady? Looks like something created a vacuum leak. It’s interesting how the MAF shows less air consumption, and the MAP shows a drop in vacuum. Maintaining steady throttle shouldn’t cause a change in the MAF much at all, and 92kpa is almost no vacuum in the manifold (something I wouldn’t expected outside of WOT). Not positive what exactly you have going on but I’d start by ruling out a vacuum leak. Outside of the obvious intake gaskets and such, don’t forget about everything else hooked to the intake, EVAP components that may or may not be hooked up, the brake booster, HVAC controls, ect. Then I suppose I may verify my MAP reading with a vacuum gauge. What are the MAP readings at idle? I would expect a stock camshaft to be in the 30-40kpa area, my cammed Camaro is only around 55-60kpa for reference. If it’s normal at idle maybe something happens while cruising, maybe it’s not a vacuum leak, maybe it’s all fucked up. Not sure how much I can accomplish over the internet with you I don’t normally work that way. Hopefully my thoughts help you, good luck. Right so I will look into a vacuum leak, I know I did have one early after I put this engine in the truck....actually forgot to hook up the PCV. But that was showing all kinds of whack readings in the fuel trims and MAP. Yesterday Warm in drive it was reading 38kpa, and 41kpa cruising at 50mph 14% tps and 100% tps is showing 95kpa. All the sensors are original to a 2004 LM7 except the TPS which I replaced a few years ago. so it may very well be the MAP, I think I have a spare around here somewhere I can see if it gets the same readings... Again I'll also check for vacuum leaks, maybe I forgot to tighten down some intake bolts.. And any help is greatly appreciated, everywhere else I ask any question I seriously just get spammed with "4l80 swap it" if it will help any Google Drive downloads for the tune and log. Tune Log ~ happens at 13:08-13:10 Quote Link to comment Share on other sites More sharing options...
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