Newbie's 1st Log 1994 LT1 Corvette, Can you have a look?

[Joshie225]

I got my SparkFun FTDI breakout to 16-pin ALDL cable assembled last night and was soon communicating with my 1994 Corvette. Today I took it for my first ever data logging drive.

The log begins with the car reasonably well warmed up, driving out of my neighborhood on city streets, shutting off the car to run an errand, restarting the car and doubling back to the freeway heading North. I chose the wrong exit and sat idling on the off ramp for nearly 10 minutes before I could get back on the freeway South bound. I hammered it up the on-ramp, cruised a few miles on the freeway and exited into my neighborhood.

https://drive.google.com/open?id=1Mw...njxnTWbxcYfJwE

During the warm up I blipped the throttle a couple of times while connected with EEHack and experienced some hesitation off-idle. With higher RPM, 1000 or so, I did not experience the same hesitation. I don't recall this hesitation when not logging, but I will double check.

It looks like my car is running lean whenever there is much load. I can see the O2 sensors responding, but still wonder if I have 25 year old sensors that respond slowly. I have new ones to go in so I can get before and after logs to compare.

I would appreciate feedback from any of the experienced sages.

Regards,
Joshua

[dave w]

Hi,
I'm in Vancouver WA also.

dave w

[F-Body Speed]

Dave w, familiar with 93 LT1 stuff any? I am in Portland, hope to move into my new shop in Oregon City in couple months.


Vince

[dave w]

Hi Vince,
I've only worked on a couple 93 LT1's. I've had success crunching data logs and reprogramming the chips. In the next couple days I'll try to set aside time to look at the .xdl posted above.

dave w

[spfautsch]

Do you have your wideband connected yet? Also, you might want to specify what mods you have if any.

I'm no sage but it seems like your O2s might be a bit lazy. Did you clear any codes before you started logging?

[Joshie225]

From what I can tell the car is 100% stock other than a K&N drop-in air filter that came with the car. The wideband is not yet installed. When I get the car on a lift to change the O2 sensors I'll see if I can add a bung for the wideband sensor.

The only DTC set in the PCM was for low coolant temperature and that code didn't activate the SES light. I cleared that code the night I got the cable together, logged the next day. The "SYS" message I'm getting persists. Through the process of elimination it appears the "SYS" message is not due to the code set in the PCM, but in another module. This is frustrating as when I previously entered CCM diagnostic mode I found no codes. I'll try CCM diagnostic mode again and see if it still gives me "ERR" when it queries module 4 (PCM) or if it shows any other DTCs.