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View Full Version : Cammed Vette, can't do WOT tune....



The Cartel
July 20th, 2008, 12:59 AM
First off, I'm a newb to this but I'll explain it the best way I know how. I have a 99 Vette that I just put a Cartek 2x cam in. When we tune with the maf it all goes fine, but when we zero out the maf or unplug it, it won't even idle. It shows it needs around 50% more fuel, it takes more fuel to idle than say at 4K rpm? Our first thought was a vacuum leak, but can't find any. Any thoughts or suggestions would be greatly appreciated.:confused:

Jason

TAQuickness
July 20th, 2008, 06:02 AM
Welcome to the forum Jason. You should be able to use the AutoVE tutorial to set you up for tuning WOT.

joecar
July 20th, 2008, 06:52 AM
+1 as TA said.

Wolverine
July 20th, 2008, 07:48 AM
Hey guys, newb here too. I was about to start a thread and read this one. I think I'm having the same issues. It's a stock 01 Camaro with cam and headers. In CL the LTFT are averaging 11 or so. I set everything up for autoVE and BAM its sitting on 20+ AFR. I've increased the idle areas of the VE table from 70ish stock, to almost 140 just to get it to idle in the 15-14 AFR range.
I've gone over the settings for Autove and I'm pretty sure they're right. I must be missing something, or just a retard. I always thought a cammed car needs a lot less fuel at idle :unsure:

John

BTW great forum with some awesome information :thumb_yello:

EDIT heres my sd auto ve .tun file

ViolatorTA
July 20th, 2008, 11:27 AM
I'm not sure where you guys are going wrong but here is my tune that got me in the right range to start auto ve tuning. In SD mode the lower rpm rows have to be lowered to idle. My old cam was way lower and I had to add a ton to that tune for the new cam but it is still lower than the stock tune.

Wolverine
July 20th, 2008, 01:09 PM
I'm not sure where you guys are going wrong but here is my tune that got me in the right range to start auto ve tuning. In SD mode the lower rpm rows have to be lowered to idle. My old cam was way lower and I had to add a ton to that tune for the new cam but it is still lower than the stock tune.

Yeah, this is basically a stock file with the autoVE parameters applied. I agree, I would think the lower rpm areas would need a lot less fuel, but thats not the case.
Thats a COS, right? Does that make a difference? I should be able to do this with factory OS right?

I'm still not sure if Jasons problem is the same as mine. But this is only the second car I've done autoVE with, and the first one went smooth as silk. But I'm at a loss with this one. Fuel pressure good, I'm 99.9% sure theres no vacuum leaks, swapped injectors, changed fuel filter. I guess I'll take off the intake and make sure the seals are good.

Heres the last autoVE file I loaded just to get it to 14's in the idle area, I just scaled the whole thing up. You should have seen it when I started applying the BEN no's :bad:

ViolatorTA
July 20th, 2008, 04:18 PM
Yes, mine is COS5 but that should not make a difference. I loaded the COS for future tuning that I have yet to get around to. Seems when I'm not taking the car to the track I don't mess with the tune, I just drive it. Havn't been to the track in a year.

The last time I had a problem with the VE table and skewed AFR numbers I went back over the tune and double checked all the VE changes needed to do AutoVE and reflashed the PCM and everything straightened out. I didn't find anything wrong in the tune but reflashing got me straight.

Have you tried re-enableing LTFT's and checked to see what the narrow band O2's were doing with trims? Might be a thought. The wideband could be on it's way out.

ViolatorTA
July 20th, 2008, 04:31 PM
WOW!!!! That is extreme changes to the VE table. Reflash the PCM with a bone stock tune with the stock VE table set for AutoVE and try to start the car. If it seems to be flooding decrease the 800rpm row by 40% and the 1200rpm row by 20% and try again. Something had to of ended up skewed in the tune. If not then you have something leaking.

Are you using stock injectors and has lifter preload been checked?

Have you idled long enough to confirme the A.I.R. pump is off and still getting the lean condition? A.I.R. will run on initial start up and show a lean condition while on.

Lastly, are you using the latest version of Live? This is 3 cases now I've seen in 1 day with the same problem. Extreme lean condition with a cam change. Mine was lean from the old cam tune but did not take such high figures in the VE table to get it right. My VE is still lower than stock in the idle region. I think I am behind on updating the software and wondering if this may be a latest release issue.

Wolverine
July 20th, 2008, 05:02 PM
WOW!!!! That is extreme changes to the VE table. Reflash the PCM with a bone stock tune with the stock VE table set for AutoVE and try to start the car. If it seems to be flooding decrease the 800rpm row by 40% and the 1200rpm row by 20% and try again. Something had to of ended up skewed in the tune. If not then you have something leaking.

Are you using stock injectors and has lifter preload been checked?

Yeah, it doesnt run real well in SD with the stock VE table:) It has been tuned some time ago with LS1 edit. I did change all tables to stock and did a full reflash, thinking that might work. It just seems likes somethings mucked up with the pcm and needs a dealer reflash.
Yes, stock injectors. Its a small cam, brand new 918 springs, stock rockers and hardened 7.40 pushrods. All the preload was normal, and it only has 55,000 miles on it.
Havent really done a long log with LTFT but average is +11 in the low rpms.
My WB is a new PLX so I dont think thats the problem

Ill try that tommorrow and let you know, thanks for the help BTW!!!

ViolatorTA
July 20th, 2008, 05:12 PM
No problem. Try going to the holden crazy site and DL an 01 Camaro stock tune and flash that cal file in AutoVE form then make needed changes from there.

Wolverine
July 20th, 2008, 05:13 PM
No air pump. I actually just installed the latest version an hour ago, so no, I was working off the previous version.

Wolverine
July 20th, 2008, 05:18 PM
No problem. Try going to the holden crazy site and DL an 01 Camaro stock tune and flash that cal file in AutoVE form then make needed changes from there.

Ok, I've already got that, thats what I used to copy stock tables into my tun file. So just do a FULL reflash with that file?

ViolatorTA
July 22nd, 2008, 12:17 PM
How has this turned out? Have you figured why you are running such high numbers?

The Cartel
July 22nd, 2008, 12:56 PM
Man, we finally got it. All along it has been a corrupted file. We ended up blowing in a OS from a 03 Vette , then going back and blow in my 99 Vettes file from months back and BAM, worked great. Apparently it wouldn't ever overwrite the corrupted data even though we did a complete reflash. Scrambling it with the 03 data got it to overwrite. I have alot to learn about tunning but, I'll try to answer any other questions the best I can.

Jason

ViolatorTA
July 22nd, 2008, 01:46 PM
That's what I figured. I had the same thing happen to me where I was commanding richer than I had tables set to command. Did a reflash and fixed it. Glad to hear you got it, now wolverine has something to try.

Wolverine
July 23rd, 2008, 01:51 PM
Hmmm, well I did a full reflash with a stock tune from holden crazy. Pulled the tune, made some minor modifications (I wanted to start from stock anyway). Drove around in CL to see if anything had changed, The LTFT still settled in the 16 to 20 range. Switched to autoVE and no different :wallbash:

I'm pretty certain it's mechanical. Hopefully We'll get a chance to pull the intake and check for leaks this weekend. Thats the only thing I can think of.

A screenshot of the LTFTs it wasnt a super long run but they were somewhat settled out here.