This is just an update on my intro thread here:
http://ecomodder.com/forum/showthrea...tml#post399117 I figured the follow-up is more appropriate here since it's getting deeper than just "hello, this is what I drive."
My last tank gave me only 30mpg. I've now adjusted the valves, inflated the tires a bit for cold weather, and cleared some stale codes left in the ECU after I fiddled with the eacv and TPS.
I doubt my mpg was affected that much by the valves, especially since they were all in various degrees of within spec. I set them all in the middle of the spec range, so the next bigger feeler gauge wouldn't slide in.
I also doubt the stale ecu codes had anything to do with it. I never had a CEL, and yes, the CEL lamp works.
However, after doing valves, I decided to double check timing. It was about 25 btdc! Odd because, I had it nailed down at 16 in the summer. I'm surprised I never had ping! Anyway I set it back to 17 btdc. I figure 1 degree advanced over spec is probably good, since I got away with 9 for I don't know how long. I'm willing to believe my timing had something to do with my poor mpg. On standard pump gas, I bet 25 degrees is enough to start seeing some power loss.
I also think my driving habits might be playing a huge role. That last tank was zero highway, and my daily commute is 9 minutes with traffic. Basically, the car never warms up, so even with my problems fixed, it never runs in closed loop. Perhaps it's time to move farther away, commute by bike, or look at an engine heater. We'll see if the next tank shows any results from the most recent tweaks.
Incidentally, when I was doing valves, I pulled the plugs and noticed #1 looked a little rich. 2, 3, and 4 were all nice. I'm running some Techron to see if I can even out the fuel distribution. I know that's a terrible solution, but I had a half bottle so I just threw it in. I've also just today noticed the return of bouncing idle. Time to investigate vacuum leaks and coolant bubbles again. Ugh. It never ends.