Novice tuning questions / issues for my first Gen 3 Turbocharged 5.3L LSx

[kingtal0n]

I just started playing with HPtuners on my 5.3. I have a couple easy novice questions.

I will post the tune file shortly (within 3 hours) but for now, I have my first questions you can probably answer without it. Fill in the blank format!

1. When I first upload a new tune (changes) the ECU needs to re-fail the maf. This results with several stalls and re-starts. It is killing my battery (I have a tiny batt atm). I am pretty dang sure there is a table where I can set the initial maf frequency/flow so the engine will run long enough to fail the maf. And the name of that table and where to find it is: _______________________

2. When I come to stop in D4 from 4th gear (didnt try any others yet, need to do that), the trans seems to downshift properly. I can watch in the scanner, 4, 3, 2, 1. And it sits at a light in 1. When I let go of the brake to accelerate from 0mph, I can feel it suddenly "downshift". It does not always happen, sometimes i actually do get 1st gear. And I think if I never hit 4th it always goes back to 1st. I am not 100% sure if it is a downshift or not, but it sure feels like a 2nd to 1st shift at 1mph. Almost like the trans forgot to downshift, even though the scanner says "1". Is this a known issue? If so, the fix is: _____________________________


And more questions, but they require my tune file, so please check back soon for more fun!

[5FDP]

Engine Diag > Airflow, set the MAF fail high to 0hz if you are not using a MAF sensor. Then set all 3 MAF dtc's to fail on first error. Also if you removed the MAF sensor, you'll need to wire in a seperate IAT sensor if you haven't yet.

[kingtal0n]

Here is the tune file, and a log of driving.

5-23-17 930pm more PE stuff.hpt

17-05-22 20-54-05.hpl

The maf fails fine after 3-4 seconds, the problem is keeping the engine running for 3-4 seconds while I wait for it fail. Everytime I upload a new tune file, it has to re-fail. The engine stalls after 2~ seconds usually so it results in restarting over and over. There is a table somewhere that tells(guesses) the ECU a maf value while it waits to "connect" to the maf, I need to change that table, but I dont know where it is. Or I might have altered it by mistake already. I thought it was "Maf Airflow vs output frequency" but I am not sure, is that my "maf table"? Does it default to the first table value there for airflow when the engine initially starts before a maf-fail?

Issue #2:
I need some help getting the scanner to record new things. It won't show me duty cycle, or KR, for example. I add them to the channels and charts but it just stays blank. I can't get it to show me fans on or off, PE mode, none of the cool stuff.

Issue #3:
It takes way too long to get into PE mode, I think. I can tell when it does because my A/F drops suddenly, but its too slow. Can you look in my tune where I've drastically reduced the pressure/tps necessary for PE mode and it still takes so long? If everything looks ok, then it is probably fine, I just need to reduce the tps% a little more. 44% is actually a lot for me I just realized that.

Issue #4:
My DFCO doesn't seem to work like it should. I need some help with the terms "enter" and "exit" DFCO for "Enable MAP vs BARO" (what does it mean?). I can't make any sense of the table which asks for KPA, while the axis is also labelled KPA. How can there be two different KPA values? Plus the row only goes from 60KPA and up, which is very odd IMO.

Question about meaning: Under "Transient" there is a box "Min Fuel Milligrams" it says minimum injector PW used to limit transient adjust fuel. Can someone elaborate ? Does transient mean when the throttle is moving? How can I use this setting to enrich or lean out my throttle movements, or is that what it is for?

As to the IAT, by the way, Yes I have an IAT wires ready to go into a sensor when I get one installed. For the time being I made it so the IAT is always 90*~ for the engine. I am not running it hard or boosting at all yet, barely going to 50% tps even. Just cruising around and trying to learn.

Also I am having trouble understanding every single setting in the Airflow -> Dynamic window. VE correction factor? I mean wtf is that stuff, does any of it apply to me without the maf? If so, elaboration is <3 love thanks

[kingtal0n]

So far I've solved issue #3, it was never an issue I just wasn't pressing down on the gas pedal enough to hit my set point TPS. Turns out, 44% feels like WOT to me lol. Even at just 30% this thing flys. I cruise around on 6% at 45mph. So now I've got PE to come in at 25% TPS, which is just about perfect as it crosses into the 65-75kpa regions and jumps down from 14.5's to 12.8's (soon to be 13.x's).

The rest, I still have no clue. I've adjusted maf talbes, DFCO tables and gotten nowhere pretty much with either (#4 and #1). The scanner I recently added some stuff so its getting better for me (#2).

[kingtal0n]

Just a little update,

A couple of things I have gotten to work for me is the injection target (boundary?), I went into the 6's slightly (just messing around) and my cruise/idle a/f dropped significantly. I was able to save some fuel. And this is just for fun atm as I plan to change the injectors soon (so it doesn't need to be 'dialed in' right now) but I thought it worth mentioning.

For the DFCO when I figure it out completely I will post how I did it. In the mean time I think I want to try leaving the converter locked for decell, so it acts like a manual trans car might (?). I never connected my TCC brake pedal switch to the ECU because when the trans downshifts 3rd it unlocks at 0% TPS anyways. I am not sure why the brake pedal feature is going to be required?


Something odd the engine does, at a stop in gear, it will idle fine for a number of seconds (30~ seconds) and then suddenly unload and the rpm will rise. I locked the timing and IACV to make sure it wasn't tune file related. The idle will rise as if an A/C COmpressor kicked off (I dont have A/C yet, no compressor) for about 5-7 seconds and then it loads back up again. My theories are:
1. water pump (thermostat) is closing for a couple seconds? (doubt it)
2. Alternator is unloading for a couple seconds? (The Generator "L" Terminal stays "ON" so I also doubt this)
3. Something with the transmission pump (Not sure but this is a scary thought....)
4. It isn't the electric fans, I verify they stay on during this
note: It only happens when the engine is fully warmed up

If anyone wishes I can post a log of the occurrence. For now I am going to test my alternator theory somehow (maybe unplug it for a bit to see if the load/unload still occurs).

[AutoWiz]

For the time being I made it so the IAT is always 90*~ for the engine.

That's dangerous. On a boosted application that is very dangerous.

[kingtal0n]

That's dangerous. On a boosted application that is very dangerous.

No, it isn't for me. Here is why:


When the air gets colder, more fuel is required. Modern engines have long intake tracts, and special passages for hot coolant, for example, that help maintain a stable (warm) air temp. On my particular setup, the air entering my air filter is warmed by the compressor, and levels out as it nears the engine, warming by the same traditions as a factory engine would (minus the coolant passage). It would take an incredibly low temperature air to actually reach my intake manifold as anything lower than typical ambient here (Florida: 85 to 100*F). Since air never gets that cold here, the cold aspect of fueling is not going to matter, as the IAT will never see "cold" temperatures where I live and operate my vehicle. And even if it did, lets say I drove to alaska for a day, at sea level, and the air temp entering the engine dropped 40*F or so, it would still be rich enough because I have enough headroom my street tune (it is very conservative, perhaps an 11.2:1 becomes 11.9:1 in "alaska" at sea level).

So that covers the cold IAT readings. Lets take a brief look at warmer temps:
When the air temp warms, the IAT is traditionally programmed to remove fuel. In a performance application, this is not going to happen (My IAT will never be pulling any fuel, ever. Nor will it be pulling timing or adding timing under any circumstances). Therefore, there will be no warm consderations for hot IAT.

This covers both hot and cold situations, as we see the IAT is useless for my fueling/timing considerations. However, it does help with keeping track (logging) of boost related temperature, which can be dangerous with pump fuel at high temperatures regardless of a/f or timing.

Last, consider that,
If you have a wideband, you can always make sure fueling is correct, and if it isn't, you grab the laptop and make it correct. Some people don't watch all the time, don't have the obsessive desire to constantly adjust their tune, but I do.

[kingtal0n]

Update time!

So here is what I've discovered so far. My DFCO works- it just reduces injector pulse to 0.5ms and not 0.0ms like I want. i suspect this has to do with the "minimum injector pulsewidth" setting? In any case, pretty happy to see it drop down like it does at least that feature appears to be working correctly. I also finally went through every single scanner-ability and added everything i thought felt important and now i seem to have full access to all of the features of the scanning tool (everything is showing up finally).

Next, The issue with the transmission feeling like it was downshifting when leaving stoplights has dissipated. Not sure what I did to fix it, but I've changed almost every setting in the entire computer just messin around, and it now acts properly at lights.

So issue #2 #3 and #4 and the trans oddity are pretty much solved. Still not sure about #1 yet though.

On to new "things":
Next, is a strange realization. When I lift from the throttle, my TCC unlocks. all this time I thought "thats pretty normal". However today I realized its set to not unlock until below a certain MPH. So why does it unlock when I lift? I read about a "decel mode" or something, I wonder if that has anything to do with it. For now, I am going to change some of the TCC setting to see if I can keep it locked during a 0% tps decel. Not necessarily because i prefer this, just curious to see what is keeping it unlocked at 0% tps.

about #1: next, I tried increasing the "maf table" to help the engine run while it trys to fail the maf, but nothing seems to help so far. It still tries to die. I have a couple other ideas/theorys to test though so not really concerned. plus it only happens when I load a fresh tune, so its not a problem once the tune is finished and the car is driving. I just like to change things ALOT so it might be something to fiddle with. In another news, i was able to find "mass air flow" in the scanner and next time i run the car I will pay attn to what it says to try and see where its taking the fuel value from in the tune (if such thing exists) hopefully that will point me out of #1.

Alright, on to the questions,
1. I like hidden switches that do cool things. I see the ECU has a "performance" and "normal" shifting character, for example. I wonder if I can put a switch somewhere to go between them?
2. One of my O2 sensor banks sudden, all by itself, pegged at 1V. The plug is not plugged into anything (I have no O2 sensors, running open loop of course). I have logs going back for months and just suddenly one day it started going up alittle, by itself, and the next day it was pegged. Ill check the plug and wires but I am wondering what this means, did I fry it somehow?
3. will think of something! lol

I really love the way the car drives, absolute blast. Attaching logs and ecu file shortly. Still driving it very slowly, like a regular work truck, no boost nothing. It flys at 30% throttle so, still getting used to it.

Log of today's drive and today's tune file. Details: 02 5.3L, 03~ 4l80e, 2-bar converted 125 OS(flex fuel OS), 44psi fuel press, stock LS1 injector, 3200lbs vehicle, no boost and no WOT tuning.
6-15-17.hpl
6-15-17, 125OS, 4l80e, 44psi fuelp, ls1 inj, 2-bar map.hpt

Other notes:
This is my first HPtuner car so the tune is absolutely experimental and potentially useless. I've changed almost every setting in the computer simply to determine what the effects are. The exhaust and intercooler plumbing are not finished yet and I have not installed the 80lb injectors or upgraded valve springs, so none of my changes are anywhere near a final, they are just to keep the car reliable while I wait on the welding process to continue (I like to drive my car while I work on it) Most changes are small, but when I found something I liked I kept moving it. I've made approx 30 uploads so far, each with a wide range of changes, such that my file no longer resembles much of the original it started as. engine starts easy and drives with a 14.8~ air fuel ratio, and PE mode hits about a 13.2:1 and gradually richens from that point (still too rich, I don't rev it past 3k yet so no need to fool with it yet) also, in an unrelated note, I am dubbing the name of my downpipe unofficially as "itchies" after unintentionally resting my arm on it.

[kingtal0n]

I noticed a few strange things.

I think there is a chart or graph missing from HP tuners. I noted that when the trans shifts from 3->4, while locked, it will stay locked during the shift, but then suddenly unlock and re-lock after its already shifted.

A second thing related to that, I noted several times where the converter wouldn't lock above exactly 62.2KPA (I forgot the exact number actually but I will pull it up again later). Clearly it has some lockup vs MAP setting but no such graph exists in my HPtuner software that I can see.

And one more thing, I started logging "TCC Slip %" And it is showing me some really high number, even when cruising while locked, like 88%. It doesn't make any sense? Not sure what effect that would have.

If anyone knows anything about this, please help!

[kingtal0n]

Today I think I solved issue #1: the maf fail issue. Over the past couple of weeks I have been gradually raising the maf table values, I believe it is in lb/hr? It started around 20 or 30 iirc, and I moved to 40, 50, 60, 70, etc.. gradually. and today finally I moved it high enough, I am pretty sure, that the engine started and stayed running nicely after a new tune upload. It took like 88lb/hr (it was around 1.25lb/min). It may have been a fluke but, fwiw I hope this was finally a solution.

I also figured out the TCC slip thing. There is another option to log angular frequency which is given in rpm of course, and it makes wayyyy more sense. My slip when locked is 1rpm or less (and sometimes negative 0.5 for example) so I think the computer knows what is going on. TCC slip still shows 88% while the angular freq shows 0rpm or near it, makes no sense, working as intended?

As to the TCC unlocking and re-locking after a 3-4 shift and having a very high shift time error, I still am working on that one. For now I raised the 3rd gear lockup so that it does not happen before my usual 3-4 shift.

And my favorite quote of the day: "Hey, why does your laptop smell like gas? actually, everything smells like gas. What were you doing?"

[kingtal0n]

So now some fuel economy calcs,

I have 7% duty cycle at 53mph. The injectors are, I believe (not sure!) LS-1 28.8lb/hr @ 60psi. I am running 44psi base, plus the engine vacuum during the 53mph cruise was 35kpa or around 9psi additional vacuum. So 44 + 9 is 53psi of theoretical fuel pressure on injectors that originally flow 28.8lb/hr @ 60psi in open atmosphere. Thats about 27.1lb/hr flow rate, times 0.07(duty cycle) = 1.89lb/hr times 8 injectors (* 8) = 15.1lb/hr fuel injected total (reminder: per hour). 15.1lbs of fuel is approx 15.1/6.3lb/gal = 2.4 gallons of fuel. at 53 miles per hour to use 2.4 gallons = 53/2.4 = 22 miles per gallon. I still don't have a speedo so this is the only way for me to tell if its reasonable or not. It might seem low, but there are a bunch of things i am going to do to improve it in the coming months. Right now for example, there is no spring in the gate. The compressor adds a significant amount of economy to the engine during cruise when spun fully by exhaust gas, but right now most of the exhaust is bypassing the turbine. I expect to get at least 2 more miles per gallon from installing a spring in the gate. I am also adjusting the rear gear from 4.11 to 3.65 in the coming weeks. There is also some weight reduction (approx 150lbs) to be done yet that I am carrying. And the tires I have are terrible, non-optimal for economy. and lets not forget lean cruise algorithms, and optimal cruise RPM, the 53mph is just a random speed that I happened to cruise long enough for to get the injector duty constant, it will undoubtedly get better economy at higher speeds especially with a numerically lower rear gear. I expect a solid 30mpg or more when I am finished with all economy details at highway speed of 65-70mph.

[kingtal0n]

Recently,
I discovered how to keep the 4l80e locked during a decel. So now I get not only DFCO but also a nice long coasting engine braking decel with injectors off. There is a table called "minimum release tps%" and if you play with that you can do this as well. Set "high speed"'s "tps low" to 0%, and make sure adjust high speed so its locked as long as you want above that speed.

I also changed the rear gear ratio to 3.69 from 4.11, and showed that at the same exact RPM in fourth as before (less than 60mph) it uses the same exact amount of fuel, even though I am going some 10-15mph faster at those speeds (40-65mph ish). Which was amazing to find out, that tells me the drivetrain weight is the big factor and speed difference was negligible. In other words, a bit more gear might help in a similar way because everything is so heavy and large, spinning slower would probably be acceptable. I wonder how a 3.5 or 3.3 rear gear would work? IN any case, I drove it 100 miles on the highway and I think that is plenty of gear for now. It feels really nice cruising at 65mph to 75mph. Once I get it insulted nicely it will feel alot like a bigger/heavier car I think (without all the heat and noise). Even though it feels heavy when I push by hand, it drives just like the original auto-car, handling wise, and its on OEM suspension still which I think helps alot.

Now with the new gear, locking at 40mph is too low for normal driving (lugging the engine until about 43mph, but ok to very gently cruise on flat). that was incredible to find out also. The RPM now around 70mph is like 2300rpm. Pretty dang happy about where this is all going.

My biggest "issue" right now is the final row in the timing map gets hit pretty quickly, like around 4psi~ of boost pressure I max out. So I will have the same timing from 4psi to 18psi? Seems kinda lame, there should be a way to re-scale that graph I just haven't tried yet (its not important yet). I wish HPtuners had a KPAvsRPM for timing just it does for fuel, but its probably not their fault (its just how the ecu does it)

A log of a 60 mile drive, the first with any spring in the gate and the new differential, so speed is off. It still thinks I have a 4.11 rear gear. That how fast I would have been going with the old rear.
And the current tune file
7-18-17 boostfuel, lockup, speedo again, vemap.hpt
17-07-17 60miles first boost with spring.hpl

fun facts:
still using 87 octane, oem engine
rear main started leaking when I put synthetic oil in. (discussion: https://ls1tech.com/forums/general-l...l#post19679455)
best accurate recorded mpg so far: 19.8mpg
goal for mileage: 30mpg