Poor acceleration/gas mileage
 

Hello everyone,

I'm having a problem with my 2002 Civic EX 2dr. The car is giving me trouble when going up a hill. Granted, it is a steep hill (mountain actually, I can coast in neutral at 70 for several miles going down it), but I top out at 50-55 (running at 4500ish RPM) and can't get it going any faster without dropping down a gear which puts me at around 5500-6000 RPM. Other cars seem to have no trouble with it. The car is also very loud when accelerating on flat ground. I'm also getting relatively crappy gas mileage (29-33 all highway). I know in the grand scheme of things that's still pretty good, but my wife's 04 Civic gets about 38 on the highway.

A couple of other symptoms. Two or three times of the course of the last 2 months the engine has sputtered heavily but never cut off right after I start the car. I've also noticed some slight bucking, again not regularly, when letting off the accelerator.

I've replaced the air filter, run fuel additive, and replaced the spark plugs. Nothing seems to have helped. Now I'm getting into more expensive solutions. I think I have it narrowed down to the MAF sensor, o2 sensor, or catalytic converter. Does anyone have any suggestions on what to try first or other potential problems/solutions?

Thanks in advance.

The converter would be my guess.

coil
 

My 03 Civic did the same thing and replacing the number one coil put it mostly right.

Thanks for letting us know.:D

try cleaning the IACV,throttle body and EGR valve if that doesn't help then replace waht you noted. also don't use bosch oxygen sensors as indicated in that thread only use NTK or DENSO. http://www.civicforums.com/forums/11...e-up-mods.html

is the cel on? Could be a dizzy. And to be honest I wouldn't go replacing things such as o2 or anything in that matter if its not throwing a code. Your cat converter may be clogged.