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Darkfox
November 5th, 2011, 12:18 PM
OK, new user. I was directed here from a friend on Ls1tech.

I showed him a screen shot of my log where LTFT was 25%, he said was VERY lean.

I've recorded a new log today, I'll also include my 2 old ones.

About the car:

2000 Camaro Z28, LS1, A4, I am the 6th owner. The car has been wrecked twice, 135k miles, very abused. Has valvetrain noise (see video) when cold, has piston slap as well. When I got the car the rear brakes were burned up, so someone has been trying to do burnouts in it. It may not have a stock tune. I can't pull the tune on it yet becaues I have to buy a 2nd license for my autocal apparently, before it will let me do that. (only shows "read E38")

Video of valvetrain noise: http://www.youtube.com/watch?v=YN98awbhxwM

Logs are attached. the first log was normal city driving. (09) it was recorded in the summer. The 2nd and 3rd logs were taken recently. The 2nd log is a spirited drive, the 3rd is mostly hard pulls from 0.

Any help is appreciated. This car is bone stock save for an SLP lid I got just the other day. The first log does not have the lid, the 2nd two do. (the video was before the lid)

Car has new nkg tr55 plugs, new autozone wires, new fuel filter, new purolator air filter. No CEL on save for P0410 during the 0010 tune. AIR pump, should not be relevant to performance. (I want to delete this and EGR, but I don't have any way of tuning, and am not terribly skilled in the ways of tunes.. I'm a noob. :lol:)

ScarabEpic22
November 6th, 2011, 08:56 PM
Update to the latest software and firmwares for your V2 and AutoCal. Then use V8 Scan & Tune to reprogram your AC with the proper files to read/write the LS1B PCM. You can read unlimited supported vehicles with EFILive's hardware, just need a license to flash changes.

So you have an AC, Im assuming you have a V2 as well but if you're a "noob", who's helping you or doing your tuning?

Darkfox
November 7th, 2011, 02:24 AM
I'm not doing any tuning at the moment, just trying to diagnose a problem, and using this device to do it. I've talked to a few people on forums who have looked at the logs/snapshots of it, saying that the car is running too lean.

I'm not certain if the car has a stock tune or not.

My AC was purchasd from black bear tuning for my 2010 GMC sierra. I'm just using the device to datalog in this case. If I need to flash it, I'll buy a 2nd license.

odd boy
November 7th, 2011, 08:21 PM
R u sure that the O2 sensors r working good?

Darkfox
November 7th, 2011, 11:22 PM
The o2 sensors (all 4) are brand new. They're Bosch, so not the highest grade.

the car also has new cats, plugs, wires, fuel filter, air filter, and a freshly cleaned MAF, IAC, and TB. I'm running seafoam through the tank now to clean out the fuel system.

joecar
November 8th, 2011, 03:50 AM
The NBO2's are pegging positive indicating insufficient fuel (injectors and/or fuel pump); presence of sawtooth shaped knock supports this.

Darkfox
November 8th, 2011, 04:14 AM
Thanks Joecar, you're not the first person to say that the car's running lean. I put 1 can of seafoam in my present tank of gas in hopes that it might help a little. I've noticed lately (no logging yet) that it's been bucking a lot MORE since the addition.

This weekend I'm going to put a fuel pressure gauge on the fuel rail and peg the throttle and see what it does pressure wise. I'm almost certain I'll see a significant drop. Idle pressure is around 58 psi.

My thinking is, if the injectors are bad the pressure won't drop yes? If the fuel pump is bad.. the pressure will?