'98 camaro-log file..first post! can someone look at this for me?

[Nine-Eight]

Hello! first post for me here... I have a '98 camaro with a forged 347- I am entirely new to EFI LIVE and am learning what I can. in the meantime, I just finished rebuilding the motor and tranny, and got the car fired up and recorded some logs of the car running. I saw a few things on the run that really worried me, so I'm not driving the car until I figure out what is going on. I'm tuner-stupid, and if someone can look at this i would be really grateful

power parts-
the car is a '98 z28 M6 transmission
forged rods and pistons
10.9:1 compression
trick flow 215 cnc heads
vengeance ported fast 90
nick williams 90mm TB
FAST 36 lb-hour injectors
stock z28 MAF
kooks headers + catted Y pipe
stock z28 exhaust catback
VRX5 camshaft, 236 238 duration, .601 .605 lift, 113 lsa
scorpion roller rockers
asp underdrive pulley


anyhow, the car is strong, but I think there is more to be had- and it has some serious issues if the log files are correct... I've attatched three log files and the base tune that vengeance set me up with.

I've got a few things in particular that I need to figure out:

the car starts very hard. I have to turn it over for 5-10 ten second bursts to get it to fire. the third log file shows the hard start, and once it starts, i have to feed it with the pedal for the first ten seconds or so until it calms down and idles at 1300

throws a cam position sensor code

* the lean fuel trim hovers around 8-14, shouldnt that be almost zero at full throttle?*

** EFI live is showing anything from -10 to 40 for the timing!**

the maf is showing a max of around 240 grams/second... I think this motor should be taking in a lot more air

very light surging around 1800 rpms

and lastly, the air bag light is on :cucumber:


anyone help me with where I can start with this? I've spent some time with the downloaded tune tool and it scares the crap out of me! I'd spend the rest of my summer trying to figure out how to tune a motor like this :help2:

Nine-Eight

[Nine-Eight]

please... can anyone shed some light on what might be going on here.... I've spent the last year dumping everything I have into this car. this car has put me through so much headache and pain....

I need help, badly. the EFI Live tool is owned by a friend, I've just bought the license and I know nothing about tuning.

I dont even know where to start looking to get this tune to a point where it won't blow up my car, let alone tuning the quirks out of it. I may be no tuner, but I know anything that pushes the range of -10 to 40 for timing has some serious, serious issues. I dont even understand why this thring runs if that is correct. and a motor of this build should be taking in way more than 240 grams/second at a 3500 elevation.

someone, anyone?

[joecar]

98, welcome to the forum.

Looks like the LTFT's indicate +10% correction.

I think you will need to do AutoVE (requires a wideband O2 sensor) followed by a AutoMAF.

See AutoVE tutorial: http://store.efilive.com/download.aspx#downloads7

If you don't have a wideband handy, you could make a map that mirrors the VE tables and follow the AutoVE procedure with closed loop enabled... but your results won't be as good as what you would get from a wideband.

With any motot build, I think a wideband would be the right way to go.

Spark timing looks ok... PCM varies timing as load changes... specifically the PCM reduces timing as cylinder airmass goes up.

Won't your friend who owns the FlashScan give you any help...?

BTW: 1997/1998 LS1's don't consume any tuning licenses.

Cheers
Joe
:cheers:

[joecar]

Looks like you have the 4 degrees of false knock that 98's are known to have...

Real knock waveform looks like a repeated sawtooth.

[TFZ_Z06]

agree w/joecar. You need to start with a VE TUNE.

1. Set Desired Idle airflow to around 14gm/sec.
2. Set Inj slopes as desired. Personally, I think yours are a little high. Try around 40.5 and 37.7, then do a linear interpolation using efi's tool bar function.
3. Turn off LT/ST fuel trims and setup for OLSD. Tune the VE table.
4. Go CLSD, work best possible on high rpm VE data. Make sure your PE table is setup
5. Turn MAF back on and fine tune it.
6. Copy your low oct table to the high octane as a start.

If you don't want to do a VE tune.
My last setup was similar to yours w/the TFS215s.

1. As indicated, you have 4 deg KR. That is because your max spark is too high. Use around 24, like is in your LOW octane table. I say this from experience w/those heads.

2. Lower the fuel inj slopes about 2 lb/hr. You are WAY TOO lean at WOT.
O2 sensors should be at/above 911mv. You are around 855.

3. A good way to set fuel inj if you don't plan to adj VE is to:
log STFT. If STFT are positive, decrease fuel inj slopes by that %. Once your fuel inj slopes are idle are closek the engine will start to run better overall.

With all that you invested, a $200 LC1 is worth the purchase as well as EFI LIVE. In fact, it is mandatory. Read all you can, everywhere you can.
I would probably suggest in your case w/limited experience, you have a shop do it for you, then you can fine tune as you will have a good base.

Good luck.

[TFZ_Z06]

oh dang, I just saw the cam position code. You need to track that down first and fix whatever is wrong.

[Nine-Eight]

Thanks for the replies guys. Figuring out where to start is the hardest part of this for me.

My buddy with the EFILive tool hasn't ever spent the time to become familliar with it or the principles of EFI tuning; He hasnt ever bought a wideband (yet) to really be able to learn how to tune.

I'll order a wideband in a couple days when I get paid again. I've spent some time looking for the cam sensor issue, and I'm thinking I'll need to replace it. which will not be fun since I think I have to drop the motor yet again to get to it under the cowl. from what I understand, I cannot start tuning this car in any way until I get the cam position sensor code issue fixed? and, what exactly does the computer use the cam positiion sensor for?

thanks for the link for the VE tutorial... and the help guys


lastly, is there a good book available anywhere that I could read for a good starting foundation for tuning?

[joecar]

Search for these authors:
Ben Strader
Greg Banish
Jeff Hartman