Its a 98 EX. D16Y8. CAI, no other mods. 102000 miles but very well taken care of as far as I know. I got it about a year ago and it was clean as hell, ran great, good MPG. I upgraded the shocks and springs, upgraded the brakes, and put in new engine mounts(stiffer ones). Then about two months ago I started getting really bad MPG, like 17 MPG. There is black soot in the tailpipe, and I have no power at around 2500 to 3500 RPMs in second and third gear. It gets alittle better in fourth but not by much. Plus it just doesn't pull as hard as did when I got it. Could that be my O2 sensor? Or is there some other something I am overlooking? Any help would be great.

 

did you ever figure out your bad mpg? I have e 93EX with the same bad mpg. the only difference is that I do not lack any performance. Its just giving me very bad mpg.

 

No, I just posted this one. Just waiting to get some help. I will PM you if I get a good answer though.

 

bump

 

with that milage, it is possible. How long have you owned it for? If not long, then you don't know the driving conditions of the previous owner (Perhaps he/she drove it hard, put in crappy gas, etc).

Do you have access to an AFR monitor? Most any tune shop can do a readout for you and you can see if you are running rich or lean. If you replace the sensor, it could solve the problem (they do go 'bad'), but it could be a different issue altogether.

 

is the cel on ?

 

No codes. Had that checked first thing. As far as a tune up, i just replaced the rotor and cap, plugs, oil, oil filter, radiator, and radiator fan, plus a full flush of the system, replaced plug wires. I may have done a few other things that i cant recall right now.

 

check your timing

 

What about idle speed? When I starthe car it idles at 1500rpms then as it warms up it drops and hold steady at about 650 to 750rpms? Could that be affecting it?

 

that's normal.
check timing.