Z-type's Tune Thread

Woohoo! First successful tune!

The first  round today I had changed all the shift times to 0.01 ms, adjusted the fans to accommodate my 180 thermostat, and adjusted the idle to 700. The shift time change didn't really do anything noticeable but the fans worked correctly and the idle was around 700ish. Maybe a touch lower according to the Aeroforce.

Now, the engine light was on when I started the car and i figured I needed a CASE relearn because, well, common sense. Not the case. I had a plethora of codes pop up.

P0101, 102, 103, 107, 108, 112, and 113. All related to the MAF, MAP, and IAC sensor voltage. No immediate run ability issues, and i cleared the codes and they didn't come back on. I did notice my fuel trims were all screwy for a few miles, but that's normal correct?

Any idea why all those voltage-related codes came up? Never heard of that before. I don't want to keep tuning and damage anything. All voltage was correct and up to snuff while I was writing the PCM. 12-12.2v.

Anywho, I wasn't happy with just changing the shift times because it didn't do a thing. So I borrowed Aaron's shift pressure table and modified (not as aggressive up top) it a bit for what I thought I wanted. And I was right . My shift times are hovering around 250ms when the trans is warmer, which is much better than the 450ms I was averaging when warm.

That all being said, I AM going to do a Performance Shift button and modify the TCC lockup more, and do a more aggressive shift pressure table for all 3 shifts. I just like the idea of having a choice of two different animals in all ranges.

Sound good so far? Still learning a lot!!

about the fans and 180 T..

In the winter, I set my fans to turn on at 205 degrees because i find it very difficult to keep my Riv at operating temperatures.

Waiting to kick the fans on at least gives the engine time to get warm during stops.

Just something to think about!

Spring Summer and Fall they are programmed to kick on much sooner to keep the engine bay as cool as possible

Any time you do a PCM flash, you need to drive the car for about 10 miles for the trans adapts to relearn. The shifts WILL stiffen up after a bit. Mine shifts like factory mush (even until the next day) until a few Ignition cycles later. Fuel trims will stabilize as well (as long as it's set right).

I have my trans shift times all set to .01, aside from 4th gear which I left alone. Normal driving and easing into 4th became *BANG* anytime I tuned 4th, so I decided to leave it be. I have my shift pressures ramped up accordingly to throttle position. I've also got my upshift and downshift speeds changed. My car WILL NOT shift into 4th gear unless I'm at 40mph.

As long as I'm not into the throttle hard, the car shifts firm and fast without being too harsh. I've found a good medium for daily driving. I'm sure I really can't compare though. The trans mods I have done probably make things a bit different than a stock Rivi trans. I'm sure turtle can confirm this as well.

Fun ain't it?

Shift time, fluid pressure, and TM are all related. Programmed shift times won't actually lower effective shift times unless the fluid pressure and torque management settings enable it. You can use shift time values to limit shifts from going below a certain period, but I don't know why you'd want that. Quicker times are desirable. Firmness from pressure and TM values are more noticeable, and probably better to go by.

My shift times are usually between .025 and .150 secs, depending on whether I'm into the throttle or not. Above .200 feels imprecise, imo.

Never have had a CASE code yet.

Fuel trims can be reset, or not, with each write. If you reset, fuel trims will read zero and then adjust as you drive. If you don't reset, fuel trims will be where they were before the program, then move (hopefully closer to zero) as you drive. I've heard people say to always reset, but both methods are acceptable.

Watch your voltage as you drive. If there is a problem, you'll see the codes again. I got a voltage code once when my alternator was sending out 17v - all sorts of lights on the dash. You shouldn't see a voltage code for low voltage. The danger when writing at low voltages is the program won't complete because PCM turns off. Then you much recover using DHP, which I've done successfully before.

Keep in mind it takes a few miles (20 mins) or so for trans shift settings to take effect. They'll be softer until the PCM accepts that they are safe for the transmission. Then your shift times may go down further. You'll feel them get firmer, too. (I see Scott mentioned this)

I leave my fans settings the same year-round. The fans don't actually speed the warm-up period, they only let the engine get hotter before cooling down. My fans turn on very frequently when idling to keep temps between about 180-190ºF.

Thank you for all the info guys!

I thought about the fans, Charlie, and that crossed my mind. Any trips I take are never terribly long, especially in the Winter, so I figured I'd just leave the fan settings to 'cool' and see how it goes. Like Aaron said, I can't see it being MUCH different.

I didn't realize the shifts could take so long to adapt. I figured since it was programmed, it was programmed and would at least be a big difference right off the bat. But hey! No biggie...that means by the time i get to work tomorrow it should be feeling pretty good.

Aaron - I'll keep an eye on the voltage but it hasn't been an issue so far in owning the car. Perhaps I can set my Aeroforce annunciator to warn me? I was real paranoid about these first two writes, because of voltage. Like I said my car was at 12-12.2 sitting there, key on, no headlights, so I was confident enough. I really hope I don't need to recover any of these days...

Thank you again guys. I really do appreciate all the responses and help and advice.

I just got done re-writing the Performance Shift tables and updating the code to enable it, as per Codith's instructions in his old thread. I'm going to wait for the switch I ordered to come in and in a couple weeks hopefully install that somewhere and upload all this new info.

Scott - you're right. This is WAY fun! I know it's cheesy, but I've stuck with making this a Riviera GS Buick would have made. Appearance, suspension and slight appearance changes - this tuning makes it more like my dad's Regal GS so far.

Do you have a spare PCM in case anything bad does happen? I keep a spare since I had my computer bluescreen mid-flash and brick my original PCM. That being said, I've done tons of flashes and have only had that one bad experience, every other time there were no issues.

Once you see how the fans operate, you'll be able to decide what works for you. The only time a higher turn-on setting will make a difference is when you are sitting idle for long periods. Whenever the car is moving, the 180 t-stat will do its thing.

You can set the Aeroforce light for voltage, or just set as a parameter and monitor volts from time to time as you drive. Save your annunciators for things you really need. I have mine set for high trans temp. KR is another good one.

Low voltage isn't much to worry about if you have a decent battery. I've done writes with mid-11v before. You only need to recover if the write fails - imo this tends to happen more on full writes, and low voltage isn't always the reason. If you write enough times, it will happen, but don't panic. Just follow instructions and should be fine. Once I was 600 miles from home on vacation with my wife, pulled over to do a quick tune at a service station. I did a full write by mistake and it failed, then it recovered (fingers crossed, got nervous that time).

Never thought to get a spare PCM. They were pricey when I started tuning. PCM is not something that should go bad, but it's possible.

AA wrote:

Never thought to get a spare PCM. They were pricey when I started tuning.

It's pretty cheap insurance nowadays. I paid ~25 for the one currently in the car and ~15 for my spare.

Alright guys, I finally have my 3.5" pulley on. I only took it down the road about 2 miles so, yes, the fuel trims are still adjusting, but i was getting some gnarly knock at 4k RPM and higher. About 4 degrees. Im going to give thr car some time to adjust, but my question is now:

How does one start to tune fueling? I cant seem to find a simple answer as to what table to start with and how. Fuel injector rate first? MAF sensor? Obviously after a few days I should try and make a scan and save it to start getting an idea where to actually start adjustment.

Thank you!

Use MAFF. Injector flow rates don't give you the kind of control you need for fueling across the range. Change in ~1% increments, then evaluate, re-tune. It takes several tries to get things where you want them.

Just to clarify, in DHP, use the MAF _Airflow Table? That's the only one I see that makes sense. Thank you Aaron.

Z-type wrote:

Just to clarify, in DHP, use the MAF _Airflow Table? That's the only one I see that makes sense. Thank you Aaron.

Yes

Sweet...I can do more research now. Thanks dudes!

Yes, that sounds right. See if you can download this excel spreadsheet:

https://www.dropbox.com/s/b8h6eihd4c9vnlt/MAF_CALC_SHEET_NEW.xls?dl=0

I made this sheet a long time ago and used it when I was tuning in 2007-2008. It will get you where you need to be faster than changing 1% at a time. If you have questions, just ask.

AA

Oh, awesome. Thanks! Looks like I really need to study this thing! Look at all the numbers.

It's not so bad. There are some instructions at the bottom. Basically you start with a stock MAF table and plug in your MAFF values logged while driving. When you do this, the sheet will populate the adjustment fields (and graph) automatically.

So before I use the chart, I do have one other question just to make certain in my own head what I'm thinking is correct.

I scan the MAFF and see how it relates to the RPM and LTFTs/STFTs. I can then make a correlation between the 3 to start adjusting the values in the MAF table little by little until my LTFTs get as close to zero as possible? I assume that using the chart with all the info plugged in will net a higher curve on that chart. Thank you again.

Don't worry about STFT for the sheet. Log a scan of MAFF vs. LTFT while at: idle, cruise, normal driving, and some heavy throttle. The idea is to get a sample of every MAFF value from idle all the way to WOT. This type of scan should take 15-20 mins of driving. You'll notice there will be repeats of MAFF values and LTFT will not always be the same - this is why the sheet has multiple LTFT input fields; they will be averaged by the sheet. The more the merrier.

Be aware of "outliers" - these are LTFT that should be thrown out, like those logged during decel or under other times when not reflecting normal driving. Logging throttle % along with LTFT and MAFF is helpful for this. For example, if you see the following values for LTFT at 4250 Hz MAFF: 4.3, 4.1, 4.3, 4.1, 5.6, 4.3, 5.6, 8.0, I would ignore the 8.0, at least until you have tuned a couple times and established a solid fueling curve. Then you can hunt down that 8.0, if it exists at that point.

Make sure all the "Current MAF" values (in green) match your current tune program. They are set to stock on the sheet, so all the "% change F/STK" fields should read 0.00%. If your MAF table (fueling) values are different than stock, you'll first need to change them on the sheet under "Current MAF".

After you start inputting LTFT data into the fields, in the appropriate "MAFF (Hertz)" row, you'll notice "MAF Adjust" column will start populating. You'll also notice your "New MAF" value (yellow column) will change for each row. These are the values you will enter in DHP to program your new fueling curve.

After your first tune, you should notice LTFT closer to zero most of the time, or slightly (-). If you see any numbers that concern you, note their MAFF values and run the sheet again. Be sure to change the "Current MAF" values to reflect the result of your 1st tune before plugging in values from your 2nd scan, and so forth. The sheet builds off the "Current MAF" values, so if they are wrong, everything else will be wrong, too. Hope this makes sense.

That looks like very much the same thing as what Table Modifier does. When I go and re-tune my heap after the block swap maybe i'll try that and see how the results compare to TM.

I'd like to see the comparison. I've never used TM, but probably much the same idea.

Well, the weather is too nasty (ice/rain/snow tomorrow) to do any real scans so I probably won't get to do anything until the weekend at the earliest...

Z-type wrote:

Well, the weather is too nasty (ice/rain/snow tomorrow) to do any real scans so I probably won't get to do anything until the weekend at the earliest...

Ah! You must be getting tomorrow what we got today. 3" of snow this morning, then some sleet on top of it, now it's raining. Everyone is pulling their cars in the shop to let them thaw. My Riv was encased in ice...
Fun fun!

We got that tonight. I cancelled a meeting - the weather is not particularly bad, but I think I am fatigued and some of the other participants requested the break.

Yeah we're getting it already this morning, it's about 7:45 AM right now. Slushy snow for now, and theyre calling for us to get dumped on around 1:00. No tuning today for sure haha.

As I type, another tune is being uploaded to the car. Changed the injector skew percentage from 100 to 110, and adjusted the MAF table as much as 10% from the middle to upper end. It needed it. Ill take a couple days to drive and let everything settle and see what happens!