I finally got the timing belt and water pump changed this weekend. Also got a new valvecover gasket because that was leaking oil. At the same time, I also got a header and an a/f gauge put in. Driving it back from the shop, I noticed that my car is REALLY lean. The shop themselves told me, and I noticed it myself. I have an SAFC in the car, and I know the obvious answer is you messed up with the SAFC but the shop doublechecked my work and the SAFC was set to 0% across the board for low and high throttle. So I did a couple of runs and watched the a/f gauge.

At idle, the gauge doesnt bounce back and forth. It just stays on the border between Stoich and Rich. Sometimes it will SLOWLY (like takes a minute or two) move from lean to rich.

At cruise, the gauge will sometimes either stay in the stoich or bounce back and forth between lean and stoich, but never into rich.

At WOT the gauge just moves up to the middle of the rich zone and stays there.

Now the shop suggested that I try correcting the lean problem by enriching the mixture with the SAFC. I did a few WOT runs and tried either leaning out or making the car run richer and noticed basically no gain or loss on the a/f. The car kinda feels like it has no power, like the RPMs will go up but the car hardly moves.

Someone please help me out! I was thinking that maybe either the timing is off, or maybe my o2 sensor is going bad. Unless its a problem with the a/f gauge. The shop did a compression check and it came out 215/215/205/215. They also did a leakdown test and it showed no problems. Thanks!

NeoVB
1997 Eclipse GS

i was actually just about to post a thread about this, my a/f used to be just like that, i just got a new front o2 sensor today and when i give it wot it stays a constant rich rather than borderline stoich and rich, get the o2 done and it will probobly help

yeah, that sounds like what it is. have you noticed a drop in your gas mileage? almost like your burning gas? if so, that's more than likely it. i still need to get a new one.
later

Sounds like an o2 sensor to me too. Just to be sure, double check the connectons to where you tapped the o2 sensor wire for the gauge. It should be soldered, clean, dry, and taped up.

remember your o2 sensor is only accurate at WOT.

your o2 sensor is shot though at idle it should go from .000vdc to .8,.9vdc but it bounces back and forth., if your car was really runnin lean you would get a CEL immediately.

and ditch the blinky light guage and do the blue wire mod for the safc, much more accurate.

and please if your gonna mess with the safc go to a dyno with a wideband and do it right

check the SAFC wiring

If one of your connections was bad (like when I first installed mine) then your car could end up running lean. I had a problem with the map sensor connection, that was causing my problem. It might be a good idea to solder that connection instead of just using the clips that come with the kit.

Definately solder the connections... and check your S-AFC setting, I've noticed a difference when you go with 6in/out and 7in/out, see which works better for you. I used one before and changed after the cams installed to get better readings and adjustability.



15.9 @ 86.7mph
97 Eclipse RS

Injen CAI, 55mm TB, P&P Intake, Crower Stage 2 Cams, Hooker Header, GS-T Muffler, AFX UDP, Crane Ign Amp, S-AFC

so you take the blue wire from the s-afc and connect it to the air/fuel wire (white with black stripe)?
later