Interprting my first data logs
Interprting my first data logs
My recently acquired Formula seems to be running rich (based on the exhaust). One piece of the troubleshooting I'd like to work through is analyzing the data logs I collected today. I'd like to determine if anything in the data points to a running rich condition, or if anything else seems amiss. I'm on the hunt for some guidance on what to look for, but I figured it cant hurt to reach out and have a trained eye take a look if possible. I'd be grateful for anyone who could do that, and/or point me to some resources.
The car is a 1990 L98 A4, and as far as I know it's all stock.
I took 3 logs:
1-cold start with ~10 mins driving (the fuel pump had primed a few times before making this start while I tried to get my ALDU1 talking to the car and TunerPro)
2-started a new log with the car parked and running. Mostly cruising, a few stop lights, and a few WOT moments
3-idling in my driveway
Ambient conditions:
76 degrees, 71% humidity, 29.75 in pressure
Side note, I've done minimal mechanical testing so far other than listening to the injectors firing, which they all seem to be. I plan to test the fuel pressure (hopefully tomorrow) and see what the plugs look like once I get a little more time to dive in.
The car is a 1990 L98 A4, and as far as I know it's all stock.
I took 3 logs:
1-cold start with ~10 mins driving (the fuel pump had primed a few times before making this start while I tried to get my ALDU1 talking to the car and TunerPro)
2-started a new log with the car parked and running. Mostly cruising, a few stop lights, and a few WOT moments
3-idling in my driveway
Ambient conditions:
76 degrees, 71% humidity, 29.75 in pressure
Side note, I've done minimal mechanical testing so far other than listening to the injectors firing, which they all seem to be. I plan to test the fuel pressure (hopefully tomorrow) and see what the plugs look like once I get a little more time to dive in.
Last edited by CamaroZ_85; May 28, 2026 at 12:56 PM.
Re: Interprting my first data logs
This exchange between Traxion and RBob is exactly the problem I'm having. My exhaust is not bearable, but mine does have a bit of fuel smell too.
https://www.thirdgen.org/forums/diy-...ml#post1610915
https://www.thirdgen.org/forums/diy-...ml#post1610915
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