02 Accord SE Idle, Hesitation, and MPG
 

Howdy all!

First time poster, long time "listener" here. In any case, I have an 02 Accord SE with the 4 cylinder engine (I believe there's only one engine for that trim) with right about 200k miles. I've recently replaced a lot of the usual tune-up items hoping this would fix my dilemma: plugs, plug wires, cap, rotor, coil, air filter. The issue is as stated above, I have a rough idle when stopped (it's great on the road), it hesitates when I accelerate from being stopped (if I'm in park it even dips down to almost stalling after revving it - really it dips down before taking off, it's weird), and my mpg lately has gone from about 28-29 to 22-23. So to the experts out there, what's my next course of action? I'm really at a loss with what to do at this point, clearly I'm no expert, so any help is appreciated. Thanks!

A few questions:

• Have you had the codes read?
• Have you replaced the O2 sensors?
• How long since the timing belt was changed?

Codes have not been read - no lights were on so I assumed nothing - the 02 sensors have not been replaced, and the timing belt was replaced at 110k

How many years since the timing belt was replaced?

About three

While I'm not a fan of throwing parts at a problem, replacing O2 sensors seems to be the exception to that rule. You might want to swap the "upstream" O2 sensor and see if that fixes your issue. If not, have the codes read anyway.

Keep us posted. :)