Well I installed an A/F gauge just now and went out for a test drive. I come to notice that the gauge is living in the RICH area 99% of the time. Only time it'll come down to stoich or lean is when i let off the gas after heavy acceleration. On idle it's running rich, acceleration is running rich, and cruising to a stop is running rich. I've noticed lately my MPG has gone down to roughly 20-21mpg even while babying it (nothing over 3250 rpm). Only mods are magnaflow axleback and level ten shiftronic system (allows me to manual shift my auto).

 

plz explain ur shifting system... hope u fix ur gauges/

 

It's not the guage thats the problem... it's the engine (ECU or whatever). The gauge is TELLING me that the engine is running rich.

More info on my shiftronic system:
http://www.levelten.com/store/import...shiftronic.htm

 

wow that is a really low gas mileage, i dont know if that shiftronic thing would affect it, I wouldnt think so. There was a guy on here awhile back that was gettin about that mpg and he only had a short ram and exhaust, I cant remember what finally fixed the problem. It was either vacuum lines or he just reset the ecu

 

What A/F gauge is it??? Narrowband or Wideband??? Seems like your gauge is accurate since your car is running crazy. Maybe try resetting your computer?! Did this happened after you install A/F gauge? Before?

 

Always a good idea to reset the ECU and see what it does then.

 

This problem happened LONG before installing the A/F gauge. I only got the A/F gauge to diagnose the problem, and i'm running it off the stock oxygen sensor (narrow band). When I did the install I had the car's negative unplugged (like I always do when i do any electrical wiring). So that already reset the ECU, imma fill up today and see how the gas mileage is.

 

thats me!

i reset the ecu, changed the oil, and let it idle for a while so the ecu could learn the new mods....

i get 25+ now with sri and catback

 

How many miles you have? Your O2 sensor might be on its way out.

 

52k miles

 

M ine left me at about 68K.... but before it was gone, my gas mileage dropped to almost nothing (kinda like now) but they were no tell tale signs (CEL or anything like that). Do you smell gas when you are idle? or any bad odours? SOmething is wrong as your mods wont justify such a loss of mileage and running rich all the time. Our cars run rich stock from the factory, but not pig rich like that.

Any other "strange" things going on?

 

Garage stinks of gas whenever I pull in and turn the car off to go in the house.

 

ha thats all im the MPw im gettin on my car...booo...i hate cali gas....so ghey....

 

AFC is the best and most accurate way of controlling it. Mitsu is known to run rich.

 

I am willing to bet it has nothing to do with the mods or guage and everything to do with the o2 sensor(s).