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FFP
January 8th, 2008, 08:21 AM
Im having a weird fuel problem with a car that im working on .It is a 427 in a 99 camaro ls7 etp heads and ls2 injectors. we did a auto ve tune and it was fine but with the maf on in open loop the afr is wacky.. when i first fire it up its 14.7 when i drive is gets a fatter the higher the rpms..when i stop with my foot on the brake its 15.5...when i put it in park its 14.7 ....can someone look at this tune and see if there is something im overlooking ?


Bill

dfe1
January 8th, 2008, 04:35 PM
I really don't mean to sound rude, but either something got whacked when I downloaded the file, or this tun file is out somewhere beyond left field. When I look at the various tables I find that idle speed is set at 1049 in gear and 1144 in park/neutral. If this is correct, and the engine has a big enough camshaft to need that kind of idle speed, your LS2 injectors are way too small. On the other hand, the injecto flow rate comes up as 60+/- pounds per hour????? Your VE table looks like a topographical map of the Rocky Mountains, and just about every other table I looked at is really strange. If these are the same kind of numbers you see when you open the file, something is REALLY wrong. If it's not, repost the file. Also, for reference, if you did an AutoVE tune in speed/density mode, then reconnected your MAF sensor, your VE table will be incorrect. With no other changes, there VE table needs to be significantly different when running MAF versus SD.

Goldfinger911
January 9th, 2008, 06:49 AM
Yeah, the injector flow rate is way off. The VE table isnt too bad, those spikes show up sometimes and need to be smoothed out. The values in the VE map do seem rather low. Change the injector flow rate and then try AutoVE again. Idle is way high too.

Is the MAF calibration correct for that MAF?

Also, have you tuned the desired airflow at idle during a full warm up cycle? (RAFIG)

I had a lot of problems getting my AFR's right after plugging back in my MAF. I dicked with it for 2 weeks, then I switched to Speed Density and it has never ran better. Just my experience, I am not saying you should necessarily do this.

mr.prick
January 9th, 2008, 02:36 PM
WOW!
don`t leave out the fact he has {B3605}
commanded fuel open loop table set to 14.63
pretty much across the board,
and {B3616} PE mode is not very aggressive (stock),
fans come on way to soon.
there seems to be a lot of things that probably
don`t need to be changed that are.
http://smiliesftw.com/x/diediedie.gif (http://smiliesftw.com)

dfe1
January 9th, 2008, 03:33 PM
Maybe this is just a test to see if anyone really looks at posted tun files. Judging by what I saw, I'm surprised the engine runs at all.

5.7ute
January 9th, 2008, 04:34 PM
Just shows how one table being out (IFR) can turn the rest of the tune to crap.

joecar
January 9th, 2008, 04:54 PM
I see those same things in that file that you see.