cantdrv65

iTrader: (3)

Ive already tried to dial in the VE table using the autove with Lc1. My commanded AFR and LC1 are spot on each other everywhere even WOT when I reenable the MAF. LTFTs look good all over the board between +5 and 0 at idle and hover between 0 and 5 throughout cruising. Problem is when I go WOT the computer starts off with a commanded AFR around 14.2 then steps on down until at 6000 rpms it is 11.7 and actually gets to 11.5 or lower by the time 6800 rpm comes around. Ive tried playing with the PE vs RPM and this has absolutely NO EFFECT on commanded AFR, it does exactly the same thing everytime. Ive also changed the commanded AFR vs MAP table for grins and it also had no effect?? I then tweaked the MAF and that simply made my commanded AFR and LC1 disagree at WOT. How do I make the computer command what I want it to command at WOT? Is it possible my VE table is off at 100kpa MAP? What makes the PCM want to add so much fuel at WOT? Id like to get this thing where i can simply adjust WOT throttle fuel by the PE vs RPM multiplier.....

slow

iTrader: (7)

is cat overtemp turned off?

Ryan

cantdrv65

iTrader: (3)

Cat converter overtemp protection looks like it is enabled.... Is that my problem?

slow

iTrader: (7)

it could be, at wot it can add additional fuel to cool the CAT's.


Ryan

brad8266

iTrader: (23)

Your commanded AFR is what you set in the PE table, your actual WOT AFR depends on how accurate your MAF and VE tables are. Since your LTFt's are positive, that extra fuel is being dumped in at WOT. What you want to do is get the LTFT's between zero and -5. That way no extra fuel will be added on top of what is usually added at WOT.

When the MAF is plugged in and you are at WOT fueling is based on MAF solely. So if your AFR is off then fine tune the MAF after you get the LTFT's beloe zero. What I did was log the maf ferquency and AFR all through a WOT run. Then match the AFR to the corresponding MAF frequency in time and adjust the MAF value by the percentage by which the AFR is off from commanded.

Example: If Stoich is set at 14.7 and your PE table is set to 1.2 all acroos the board that makes commanded AFR 12.25. Now lets say you log and at 4000RPM's you are at 11.5 AFR. You then determine the percentage of how much the actual AFR is off from commanded. This is calculated by commanded/actual = 12.25/11.5 = 106.5 %. You then will go to the MAF table and adjust the cell for 4000RPM's and increase the value by 106.5%. This is how I did it and my AFR is dead on what I command

There may be a easier way to do this in EVILive, I use LS1 Edit so I gotta do it the hard way.

cantdrv65

iTrader: (3)

Thats great but the AFR and LC1 are right on top of each other...They agree. The computer is calling for 11.5/1 and it is getting it. Ill assume that means my VE table and MAF tables are correct. As I said I changed the MAF table and this simply made the commanded and actual LC1 measured values disagree so I put it back like I had it. Thats not the problem. Also adjusting the PE vs RPM table or the open loop commanded fuel does absolutely nothing to my WOT mixture. The PCM continues to call for around 14.0 on tip in to WOT at 2500 rpm then progressively steps down about .5/step....By 6800 rpms Its calling for 11.5 or so....The LC1 is agreeing and follows the steps down spot on.....

brad8266

iTrader: (23)

Is COT on?

cantdrv65

iTrader: (3)

Yes, will this override the PE vs RPM table? I have even set the PE vs RPM to 1.00... No dice. Ill disable the COT tommorrow and see what happens.

brad8266

iTrader: (23)

if its set to 1 that should put you at 14.7 at WOT. yeah disable that COT crap and see how it works. Keep in mind you really should get your fuel trims negative rather than positive, the positive trims will make the PCM add even more fuel at WOT. You might want to completey retune closed loop to get it negative before you go any farther. if your the fuel cell you are in right before WOT is +4 then the PCM will add 4% more fuel than is called for at WOT, so it will make you rich.

cantdrv65

iTrader: (3)

Ive had the trims at 0 makes no diff....

Doc

iTrader: (9)

Just a stupid question but, you used Autotune to do the VE table correct? Autotune has you put the whole 3605 Commanded open loop fuel table to to stoich, 14.63 or "1". You did put the 3605 table back after the autotune? I only mention this because I never, ever have forgot to change it back.
If you logged commanded vs. lc-1 actual, which it sounds like you have as described it would comand rich and your lc-1 is saying yep I'm rich, now what.

cantdrv65

iTrader: (3)

yep its back to 12.95 at the areas in question. I also raised those values trying to lean it out no dice. Hopefully the cat overtemp is causing the problem....

Yeah the Lc1 is agreeing with commanded.

muncie21

iTrader: (14)

Have you checked OLFA? I believe at WOT the PCM will take the richer of the two (PE or OLFA).

SSpdDmon

iTrader: (10)

If COT is on, it will add fuel after a few seconds of WOT. It usually hit my car around 3rd gear. Turn it off and you should see the commanded AFR reflect the PE and Fueling in Open Loop tables.

cantdrv65

iTrader: (3)

Guys you were exactly right! The cat overtemp protection was the problem! Disabled it and now the PE vs RPM works perfectly! I think Im done with my tune.

The cat overtemp has its OWN set of commanded fuel numbers and eventually ends up at 11.7 AFR no matter your PE settings!

Thanks!

brad8266

iTrader: (23)

Cool man, glad you got it working.

silverTA2002

iTrader: (1)

Exactly. If you put PE to 1.0 and your Open Loop F/A table calls for 1.13, you'll get 1.13 fueling.

My stock OLFT table is 1.13 at WOT, so anything below that for PE doesn't make a difference.

cantdrv65

iTrader: (3)

Correct. But if you have Cat Overtemp Enabled, both OLFT or PE will do absolutely nothing.....

Mat

Yep. COT is a bugger. I had the same issues while tuning with the wideband a couple nights ago. Kept trying to make the PE do something, it didn't. Then after we switched off COT bam we were sitting pretty at 12.9:1. Maybe a touch too lean at WOT right now but I can fuddle with that later.

Also, to note, we set the PE to 1.13 (commanding 13:0x:1 AFR) and then simply scaled down the MAF airflow readings for the given frequency range to get my target AFR.

gogogadget

iTrader: (1)

I am having the same problems trying to tune with a wideband. It didn't matter what I set the PE values to be, it always ran 12.0:1 AFR and the car ran the same ET/mph. This is with a stock cam and stock program.

Does this COT thing matter if I have no catalytic converters? And yes, I am an HP Tuners newbie.