Assassin

iTrader: (3)

basically if I put the olfa table to 1.00 across the board my wideband should read 14.7ish correct? (its reading 13.4ish), my pe table is set to 1.00 also, I'm trying to lean out idle and part throttle but got stuck w/ a rich condition, though I'm tired and its late, maybe I missed a table..., right now the olfa is accurate at 11.7afr (1.25), why not at the 14.7 (1.00)?, I set the whole table to 1.25 for a steady rich tune to get the ve table right, could I have foul'd my plugs running rich during part throttle/idle earlier today, and now its reading rich??

Black02SS

iTrader: (36)

Nope. You are runing into the same problem that I ran into a few years back. You can't tune the car with a OLFA table of 11.7 and then change it to 14.63 and it be accurate. You need to now change the table to 14.63 (1.0) and retune the ve table again.

TAQuickness

iTrader: (28)

In theory, what you did should work, but as Chad pointed out, real life is different.

SMOKINV8

iTrader: (6)

Chad, could that likely be the problem I ran into when I was expirementing with OLSD? I did not change the OLFA to 1.0.

https://ls1tech.com/forums/pcm-diagnostics-tuning/490444-experimenting-open-loop-vs-speed-density.html

foff667

iTrader: (2)

Thats why when I was doing the writup for the hptuners help file last year with the help of humpinss and a few other members we came to agreement of putting the olfa table to 1.0 & setting the pe table up as you would want it to be once your done with the tune...theoretically it should work set to anything but in the real world nothing ever works the way you want it.

Black02SS

iTrader: (36)

HumpinSS and I came to this conclusion some time ago. I have brought back a OLD thread that shows what exactly happens when you do this. SMOKINV8 this is exactly your problem IMO. Check out the thread.

https://ls1tech.com/forums/pcm-diagnostics-tuning/308517-afr-changes-open-loop-multiplier-table.html

Assassin

iTrader: (3)

well just to experement I also tried changing it to like .91 or something and it went lean to 15.4ish, maybe I'll just turn down the olfa table lower than 1.00 to make it read where I want under idle and cruise... because its more important that the ve table is correct on more fuel so I can make adjustments when under load and they will be more effective, correct?

thanks for the help guys, good to know I'm not retarted, I knew it was late lastnight but I didnt think I was missing anything..... also, is it worth it to turn off all fuel multipliers or not mess with them?

Black02SS

iTrader: (36)

You really need to dial in the VE table to what AFR you are wanting. If you desire to have a 14.63 AFR, then set the OLFA Table to 14.63 and readjust your VE table to match. Anything else is just fudging the numbers which we have tried so hard to figure out how not to do it like that.

SMOKINV8

iTrader: (6)

Looks like that matches up pretty consistently with what I was seeing, just in an opposite manner. You were trying to go from a richer VE to stoich, and I was trying to from stoich to a richer AFR for OL testing. My wideband kept saying I was lean, and yours was saying you were rich.

Just one more thing to play with when I get the time, thanks!

Billiumss

iTrader: (11)

So are you guys trying to tune the whole VE table to 14.68 A/F in OL SD mode?

foff667

iTrader: (2)

i generally leave the cells up to 150F stock and change everything else to 1.00 then set pe up the way I'd like it to be at the end of the tune...so everything except pe mode yes it will be 14.7:1

white2001s10

iTrader: (4)

I would personally never do that.
I think maybe the majority of people out there are trying to get ALL of their fuel trims as close to zero as possible for closed-loop operation, but that's not saying that's the best thing to do.

Assassin

iTrader: (3)

I'm doing 2bar sd ol w/wideband, I've got no fuel trims, I tell the car how to run and it does it now, but my ve table is up to 210kpa and yeah I was running olfa on the rich side for the ve table to be right under load, I can back down the part throttle and idle area's easier and faster than I can adjust for wot, and I dont plan to put that stupid maf back on the car...

thanks again black02ss, I would have been chasing my tail for days trying to figure out its not accurate from such a big afr change...

Black02SS

iTrader: (36)

I have been tuning vehicles at 14.7 in OLSD for over two years now. This is the ONLY way to tune a car IMO as I do not trust stock narrowband oxygen sensors. If you ever use a wideband after you have tried to tune a car with the narrowbands, you will see what I am talking about. I can take a car that was dialed in perfect to 14.7 with a wideband, re-enable closed looop and the trims will be off, they shouldn't be as 14.7 in closed loop is the same as 14.7 in open loop. Do some searching and you will see this method is the correct one that has been tested and tried.

Billiumss

iTrader: (11)

So what you are saying is that from MAP 75 to MAP 100 (Engine Temp at 180-200 F), you still tune it to 14.7 A/F at all RPM's using a wideband?

Wouldn't you want to richen it up as the more load you have (going from Map 75 to Map 100)?

Black02SS

iTrader: (36)

Nothing was ever said about PE mode. I don't disable PE so it will richen up the car when you go WOT.

Billiumss

iTrader: (11)

I guess there is more than one way to skin a cat here. So your saying the same applies to boosted cars, tune the whole VE to 14.7, even at MAP 150 and higher?

When I tuned the VE, I turn OFF the PE, set it all to 1.00. I then step the A/F from say MAP 70 to MAP 105 (14.7 down to 13.0) for N/A cars. Ltrims are dead nuts on and NEVER have any lean spots when it goes into PE mode.

I'm not debating anything, just surprised.

I'm going to check the stock VE in my new 2006 Silverado LQ9 in OL SD and see what A/F it shows with PE disabled. Should be interesting...

Black02SS

iTrader: (36)

My method only applies to N/A. You can do it the way I suggest or your way. I have found that if you eliminate PE you lose a little throttle response due to it not actually hitting a richer AFR until you are at a higher MAP, the negative is you can consume a little more fuel.

For Boosted cars, I would only set it to 14.63 until the car makes boost (105kpa) and then after that richen it up or have PE activated as soon as boost kicks in.

SMOKINV8

iTrader: (6)

hmm... would it then make sense that the stock VE is tuned (on a stock motor) to match AFR's desired in the OLFA table?

Fwiw, I also do things as Chad explained. I just don't like the idea of turning off PE. I guess I consider it like my little tuning security blanket.

Black02SS

iTrader: (36)

That could be a posibility... I have never tried to tune a stock car with the stock OLFA table. I have always changed it to what I want.

For PE, you can always leave PE enabled like we do AND have it set in the OLFA for even more security if for some freak chance it doesn't hit PE.