KR elimination

[bonnevillain]

this makes me want a tuner so bad!

[superchargedSSEi]

My butt dyno picked up an increase in power after tuning as well. Even if the power increase was just my imagination the increase in gas mileage and throttle response after tuning was reward enough.

I'm surprised the PCM relearned the trims fast enough that you were able to squeeze in that many VE and MAF adjustments in such a short amount of time. Is your LTFT locking in at zero everytime you enter PE mode? If there are zeroes in every cell where the MAP is >100kPa...kudos and congrats. If not...you may have rushed the tuning and shouldn't be moving on yet.

[99ssei]

Through the HP Scanner, I'm seeing LTFTs at 2 in the far left column.
Should I continue to chase the last 2?

[TommyGloves]

The problem is my bonneville uses a PWM controller for the fuel pump. Should hear back from Caspers today.

Small world....I just at Caspers the other day picking up some stuff. Justin was telling me about this 99 Bonneville that was having trouble with the FP hotwire kit. I guess this was you. He sounded pretty confident that they had the problem fixed. (Justin knows his stuff.)

Glad to see your making progress on your KR and learning to tune. It's a whole new world of frustatration and enjoyment all at the same time.

As for those asking about the 2000+ models and the hotwire, according to Rogue, it's not needed.

[99ssei]

Yup, Justin was referring to me. He was nice enough to call me on his vacation to help trouble shoot the kit over the phone at 7 o'clock at night. Good guy. I need to call him tomorrow and find out what's the end result. I guess the good news is, they'll be able to do others like mine. Get your wallets ready gentlemen.

[superchargedSSEi]

Through the HP Scanner, I'm seeing LTFTs at 2 in the far left column.
Should I continue to chase the last 2?

Yes. When the MAF is done right the only LTFT value you should see while in boost is 0...really the only LTFT values you should see are 0. Only then do you move on to getting your O2 or AFR values where you want them.


Looking at the latest histogram (should've caught it on the earlier ones but I didn't) I see that you're getting into boost at very low engine speeds (1200-1600rpm rows mainly). My guess is that either the TC is locked up creating a high engine load, or you've done the BCA mod that allows you to get into boost a little quicker. Whatever the case is it's probably skewing your average LTFTs. Look through the raw scan data and you should see how the LTFT differs when, for example, the MAF reads 8500Hz @ 1600rpm vs 8500Hz @ 3200rpm. When the new MAF table is created, data for both cases would be used even though there is an abnormally high engine load at the lower rpm.

Also, it looks like you're collecting data while decelerating from high engine speeds (20-30kPa column gives it away). That data is garbage too and can throw things off if you use it. If you set the Fuel Trim Cell as one of the parameters to scan, you can filter the data by it. Toss out anything with an FTC of 0 to get rid of any data collected under regular braking, or while engine braking after a quick sprint.

Any chance you could upload the .csv file of the raw scan data somewhere it could be downloaded? A quick run of that through some spreadsheets and software I have should highlight any potential trouble areas.

[99ssei]

Thanks Aaron!
I meant the far right column (under boost), sorry.
That's really good information! How do I know if the TC is locked up? What's a BCA mod? I'm guessing Boost Control Actuator? I'm positive I haven't touched either. If this helps, at anytime, I can make KR jump if I stomp the gas pedal hard while at cruising speed (doesn't really matter what speed). This has always been an issue. I've just learned to downshift before stomping the gas.

Tonight I will look into logging MAF data in Hz and adjusting the FTC so I stop capturing deceleration data.

I can upload the file, but don't know where. Maybe I could send it direct? Send me a PM. Thanks!

[bonnevillain]

TC should be locked up at anything over 47 MPH, and youre not getting into the throttle IIRC
the reason KR spikes when you stomp on it at cruising speed is because the TC is locked up. if you downshift first, it unlocks.

[superchargedSSEi]

Really all of the cells in the histogram should read 0 if the tune was perfect, but close to 0 is good enough. When your LTFT locks in right though you should see 0's in every cell where the MAP is reading 100kPa or higher, that's a must before you move on to other parts of the tune.

You know those annoying times when you're cruising down the highway and give it a bit of gas to pass someone, only to find that the engine really isn't revving even though you're at half throttle? That's the torque converter locked up...it'll do it in 3rd and 4th gear up to a certain speed or rpm. I usually start scanning in 3rd gear at highway speeds to avoid lockup altogether. If I'm at a lower speed I pop the throttle first to unlock the TC, then roll on it for the scan. If you're cruising in 4th, downshift it to 3rd and the TC will automatically unlock. You want to do the majority of your scans in 3rd gear as it offers the best resolution. 1st and 4th gear scans are usually avoided.

[Allmachtige]

Wow Aaron great info!

BTW, what scanner is this again 99ssei? I need to look into this. I'll crap myself if a custom tune is all I need.

[99ssei]

BTW, what scanner is this again 99ssei? I need to look into this. I'll crap myself if a custom tune is all I need.

VCM Suite by HP Tuners comes with both the Tuner and the Scanner. I bought mine through Intense to avoid sales tax (both you and I live in IL. HP Tuners is in Buffalo Grove, IL). I also have the Aeroforce Scan Gauge when my laptop is not connected to the OBDII.

Allmachtiage - have you even had a tune done before? Besides the canned PCM tune from Intense I bought two years ago, this is my first tune.

[Allmachtige]

BTW, what scanner is this again 99ssei? I need to look into this. I'll crap myself if a custom tune is all I need.

VCM Suite by HP Tuners comes with both the Tuner and the Scanner. I bought mine through Intense to avoid sales tax (both you and I live in IL. HP Tuners is in Buffalo Grove, IL). I also have the Aeroforce Scan Gauge when my laptop is not connected to the OBDII.

Allmachtiage - have you even had a tune done before? Besides the canned PCM tune from Intense I bought two years ago, this is my first tune.

No tune here. I just bought an Intense PCM and slapped it in at Casper's with the help of Justin's Tech II.

[99ssei]

I bet all you need is a custom tune. Every car is different. The canned PCM gets you close, the tuner dials you in real nice!
My dyno verifies that! I just wish I bought it sooner. And to think, it all started with the scangauge I bought back in June. I'm surprised I haven't blown anything up by running lean for so long.


EDIT: On advice from Aaron, I was able to download the factory 1999 GTP bin file from HPT site. I plugged in the factory timing and left everything else the same. Much better now! I'm running rich in the 1000-3000 rpm band, but in WOT, I'm locked in at 0.0 LTFT. I only had two WOT runs yesterday (67 degrees and raining) and I only saw one KR cell hit "1" !!
Still a little skeptical because it's not 80+ degrees outside. I'll work on leaning out the lower end and post the chart when near perfect! (almost ready for race day - Sept. 13th!)

THANKS AARON!

[99ssei]

Okay, I'm a bit stumped.
It was 74 degrees & low humidity here. I have my LTFTs in good range, however my far right side are now -2.
Looking at my O2s, I'm not between 930-940. If I'm running a bit rich in the upper end, shouldn't my O2's confirm this?

[superchargedSSEi]

Your O2s will be all over the place with the narrow band. I've seen mine go as low as 880mv with an 11.5:1 commanded AFR. What concerns me is how low the O2s are in the 100-130kPa range. My guess is that your PE enable throttle position is set too high. Try setting it at 35% for all engine speeds 2800rpm or higher and see if that clears it up. If your scanner is recording the MAF in Hz I could get you a more exact PE enable point.

[99ssei]

My PE Enable Add vs. TPS is as follows:
0-35% - 2.00000
40% - 1.79980
45% - 0.71973
50% - 0.45020
55% - 0.25977
60% - 0.09961
65% - 0.00977
70-100% - 0.00000

Hot PE enable TPS vs. RPM:
50% all speeds.
I'm changing all to 35% for 2800 and up.

I'm logging MAF data in Hz now, so I sent you the file.

[superchargedSSEi]

Looking at the scan your O2s while in PE mode are almost spot on. As expected the PE trip point was too high so the pcm was still alternating between rich and lean, dragging the average down. From the data it looks like your PE enable point should be ~30%. The program wasn't happy with the .csv file so I couldn't get you a better estimate, but that throttle position should be good for most situations. Expect the LTFTs to move around some once the new trip point is put in.

Edit: Just got the new scan. Looks much better with minimal KR, O2s are back up to 915-940mV for the most part. Still getting into boost around 30% throttle so I'd still drop the PE trip point a bit more. If it bogs or kicks in too soon for your driving style you can bump it back up at the lower rpm's.

[99ssei]

Okay, my LTFTs are within tolerance, yet I'm still having KR. I've set my PE enable to 30%. The images below were on the way to work this morning @ 58 degrees. EDIT: Also note that DTC P0440 came up (EVAP). Looking into getting a new canister.

[superchargedSSEi]

What are the O2s and IPW doing when you get KR?

[99ssei]

Hitting 5.0 KR..same scan from above:




A little bit later in the scan, KR hit 6.2: