Wants to pull in gear

[epfatboy]

Got a 6.0 with a 4l80e and using a P59/DBW setup.

The tune came from a similar build except it was a DBC.

I just got this put together and just started setting up to tune her.

It idles fine but when I pull her in gear she brings the rpm up a bit and wants to pull, it feels like it pulls harder as it starts moving.

Any clues where to start would be a great help.

The tranny is a performance unit from Hughes and is known good. Converter is a 9.5 3400 stall from yank and known good as well.

I'm an intermediated tuner at best. The tune I'm starting with is a 6.0 with the same cam and injectors and tranny combo so I know it's close. One difference is I have DBW and the orig tune is DBC.

[gametech]

You have to post the tune before anyone can check it for problems.

[epfatboy]

Yeah... sorry about that thought I included it last night, I think I got it attached right now.

[epfatboy]

Also I do have a log but pretty sure the channel list isn't right, I can take a new one and include the right channels... just need to know what folks might want to see.

[edcmat-l1]

Also I do have a log but pretty sure the channel list isn't right, I can take a new one and include the right channels... just need to know what folks might want to see.

Post what you got.

[epfatboy]

Alright, just took this one.

I noticed it will settle in around 1500-1600 RPM in gear foot off brake. Check out around the 9 min 10 sec mark, foots off the gas for 30 sec I used the brake to slow her down half way thru.

[edcmat-l1]

Your description of how it feels, combined with the data log, do not look and sound like a 3400 rpm converter. It should be much looser than that.

Anyway, here's a screen shot. Looks like most of it is added air from your throttle cracker. But it sounds like the converter is too tight to me.

Idle airflow_b.jpg

[epfatboy]

I really don't want to agree with you... but it does feel that way for sure.

And while I'm not the best tuner the Throttle Cracker values in the tune are from a stock '04 LM4 which I know isn't perfect but I don't think it would push the car?.

The reason I felt the converter was good is because I bought it new, ran it a year no worries with this tranny behind it too, then threw the converter/tranny behind this motor over the winter.

I'm not sure if this even matters but the tranny is a built hughes unit, this tune has line pressure changes amoung other tranny mods, anyway those 2 things are impacting this? Not sure any of that matters given the valve body/noid changes but thought I'd throw it out there.

ALSO,
about those cracker values, I don't have a PNDL switch and it's disabled thru the tune... Is that why it appears to be adding air in Gear and P/N while I'm in Gear?

[SiriusC1024]

Log TCC slip rpm.

[abc]

At this point it doesn't really matter if the converter is as loose as you think it is or not, I assume it's a street car that you do not want it to idle at 1600 rpm. You need to find where the air is coming in and cut it down. Study everything that controls idle air flow and look at the STIT, I assume it's pulling max amount in an attempt to get it under control. My first guess is the base running air flow is not correct and the throttle cracker is adding to the problem?

[Alvin]

This thing is really rich. It likely has air it doesn't need to make it idle rich.. Which is later causing it to pull down the road.

[epfatboy]

Thanks for the responses, yeah it?s really rich, this was the first real drive.

I?ll find/pull the idle adders throw a few tranny channels in the scanner and post up a new log. I?ll check the base air also.

[edcmat-l1]

At operating temp the idle trims are pulling .7 g/s. That means the BRAF is pretty close at least at op temp.

Need to put it back in closed loop and use your fuel trims to dial it in.

[Alvin]

Thanks for the responses, yeah it?s really rich, this was the first real drive.

I?ll find/pull the idle adders throw a few tranny channels in the scanner and post up a new log. I?ll check the base air also.

a rich idle will drive the airflow demands for a idle way up.. I'd get the fueling under control before spending too much time on the idle.

[epfatboy]

Thanks again all..

I do have some good news.

For starters, I pulled 10% of the VE across the board based on observed AFR on my gauge BECAUSE I have been struggling to input the info from my serial port. This leaned out the AFR by a little more than a point at idle and while out on a short 2 min drive.
Unfortunately that didn't impact the pulling problem, but hey the good news is I replaced my HP laptop with an IBM laptop (little older) and my serial input is working so I can finally get the car on the road for some decent tuning runs.

I ALSO changed tranny line pressure settings associated to upshift (base and gear shift values) as I noticed the 1->2 shift was WAY too harsh at part throttle. THIS change appears to have greatly improved the issue of the car pulling...??? It's raining out now but here is a quick log with a few tranny related channels and the tune with the changes I have made. Basically the car isn't pulling but I think it still kicks the idle up a bit so more tuning required for sure.

It's not perfect but now that I have my WB feed and this (for the most part) out of the way I'll start the process of getting this dialed in.

I haven't tuned a DBW setup or one with a MAF yet. I figured I'd follow what I've read/watched which is,
- Go Speed Density
- get the VE close,
- set the MAF baseline,
- then turn the MAF on and tune the MAF (afr err)
- re-enable closed loop

Hoping all that gets my fuel in decent shape before I start asking alot more questions about tuning for idle..

[gtstorey]

- then turn the MAF on and tune the MAF (afr err)
- re-enable closed loop

Need to put it back in closed loop and use your fuel trims to dial it in.

[gtstorey]

I’m pointing out the closed loop with trims Tuning suggestion not the maf.

[epfatboy]

Okay, I hate to leave a thread hanging so I thought I'd update...

I believe one of my problems starts with coping a tune... Sure it's a good thing to start with a known good tune thats close to your config but if your a DOPE and copy/paste DBC configs in a DBW setup you might have some troubles... says the Dope. So I copied a few tables/settings from a stock 2004 LQ4 DBW 4L80e tune (the original tune for this PCM) and it feels better but I'm not out of the woods.

ALSO:
I have turned just the MAF on and it drove like shit (surge in gear while rolling and "cruise control" rolling idle)
I have put it in closed loop w/Maf and it drove like shit (same as above)
Put it back in SD and it's much better, not as much surging but I still get that cruise control feeling.
The VE table under 4000 RPM is tuned within +/- 5% in SD, I'll touch up the upper RPM ranges when I feel its safe

So my question:

I tuned my BRAF while the car was in SD, thats OKAY right? The values came back about 20-25% less than what I had but it's about 66% more than stock values.

My airbox is a little restrictive so I thought I should try to dial in my MAF a bit before I enabled the trims. Is that the right way to think of it since I have the VE table close?

I'm tempted to run without the MAF and see how she runs with just the STFT's, would that help me diag/fix the surgeing and cruise control issues I have?

Anything I should log in a scanner to help ID the problem?

[SiriusC1024]

What injectors are you running?

[bk2life]

Sometimes it is much easier to load up a 100% stock file and start at step 1.

Get it to start and run.

Then start your datalogging. Most of what you have done appears to be wasted time, as you had the tables messed up for dbw/bdc.
It happens, mistakes are normal. Don't let it eat you, just have some fun with it and start over.