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zapp168
November 18th, 2021, 06:19 AM
I am tuning using 7.5 doing auto VE on an 0411 computer using an AEM wideband. I am rich at idle and low rpms and lean up top, as I drive and log, the log file plainly shows this. I copy with labels, then paste and multiply with labels and the VE table looks like it should with some dips and spikes, I do some smoothing and flash. When I drive it next time it is leaner up top and the bottom is virtually the same or a little richer, I log again and I get virtually the same looking numbers.....I am losing my mind! The VE table started to look almost flat and vertical as the low gets lower and the top gets higher. I just reverted, but it does the same thing?

Any ideas?

pinstripebob
November 18th, 2021, 06:51 AM
Can you post a tune and a log? I've found that not getting enough of the table logged and then using the smoothing buttons will overly smooth or flatten my VE table, changing areas that don't need to be changed. If you're fine tuning, you might try smoothing modified areas by hand and see how that works for you.

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nonnieselman
November 19th, 2021, 04:20 PM
Yea i wouldnt smooth and see if it helps.
Is this on your WS6?

zapp168
November 20th, 2021, 03:20 AM
Yea i wouldnt smooth and see if it helps.
Is this on your WS6?

No I have an 88 RX7 with an LS3.
So in frustration I increased the injector flow rate 60% and my idle AFR remained in the high 12's. I will post my tune up later, but I am now suspecting the cheap EBAY injectors that I bought when mocking this all together. I used the same computer and set up from the LS1 that I had in there for years. it has always run super super rich since the swap. I just never put a wide band on it until now.

zapp168
November 20th, 2021, 08:46 AM
The car will idle at 12-13AFR no matter what I set anything at. Injector flow rate increase, VE table set to 0 at idle. Two different sets of injectors, if anyone has any clue please let me know.Thanks

nonnieselman
November 20th, 2021, 02:48 PM
What is the Injector pulse at idle?
Ive had nothing but problems out of cheap injectors so i make everyone buy new ones with data and it makes a world of difference.

Is this a LS3 with a 24X reluctor? I see your using a LS1B PCM.
Ive had some large injectors in a Turbo 5.3 with a stock cam and couldnt get it any leaner than 13.7afr at idle no matter what i did. Found out that the injectors were firing at their minimum pulse so that was a little fuel possible they could flow. I ended up turning the fuel pressure down from 60 to 35psi and it worked. Got the idle AFR up to 14.5 and ran great.

Highlander
November 20th, 2021, 05:52 PM
make sure your injector pw at idle is not less than b4003. otherwise it will not pull fuel after reaching this min limit.

zapp168
November 21st, 2021, 08:14 AM
So the whole "opposite" effect thing came from me logging and the idle AFR never changing, so I kept going over it and over it until the table just got way out. I swapped out the 60's I was using for a set of 42's and it will now hang more around 14.5-15.2 but then just slowly starts to migrate back down to 12.8. I can't imagine two set of injectors......although cheap....doing the same thing. The tune was originally running the 5.7 with a large cam and heads with no issues. I have used my scan tool and all the readings look "normal" MAF, MAP,. The LT fuel trims are just stuck at -17 all the time.

zapp168
November 21st, 2021, 08:15 AM
What is the Injector pulse at idle?
Ive had nothing but problems out of cheap injectors so i make everyone buy new ones with data and it makes a world of difference.

Is this a LS3 with a 24X reluctor? I see your using a LS1B PCM.
Ive had some large injectors in a Turbo 5.3 with a stock cam and couldnt get it any leaner than 13.7afr at idle no matter what i did. Found out that the injectors were firing at their minimum pulse so that was a little fuel possible they could flow. I ended up turning the fuel pressure down from 60 to 35psi and it worked. Got the idle AFR up to 14.5 and ran great.

What injectors do you recommend? I am running ID1000's in my T/A but i'd rather not spend that kind of money if i don't have to.

statesman
November 21st, 2021, 09:14 PM
The LT fuel trims are just stuck at -17 all the time.

I came across this problem once a few years ago... was a corrupted OS. If you've got an old version of your tune that you know is good, then full flash in that old file and see if the trims are still stuck at -17. If the trims are still stuck, then you'll need to do a full flash with a stock tune file... only making basic changes to the tune before you do the flash, things like injector flow rate so the engine will actually run. You'll then have to start tuning from scratch.

joecar
November 22nd, 2021, 04:33 PM
Also, when you did AutoVE did you make sure that the MAF is failed and trims are disabled.

Also, btw, increasing the IFR will cause the ECM to fire the injectors for a shorter time.

Did you populate the injector tables with data for the new injectors...?

See what Highlander said above.

+1 what statesman said, when fueling doesn't respond to airmass changes, something is really wrong.

zapp168
November 24th, 2021, 03:08 AM
make sure your injector pw at idle is not less than b4003. otherwise it will not pull fuel after reaching this min limit.


Do you mean B4003 vs the lower RPM's on B4001? B4003 is .8 and with the 60's B4001 is 8.7's.

Is that what you meant?
Thanks

Highlander
December 1st, 2021, 07:51 AM
I meant: make sure your injector pulsewidth at idle is not less than b4003. otherwise it will not pull fuel after reaching this min limit.