First off, I suck at working on cars. However, I do what I can myself and have found in hindsight that things often aren't as daunting as they seem initially.

I own a 1996 Honda Civic HX with 229,000 mi on the odo. Currently the vehicle is throwing 3 codes.

P0171 - System too lean - Bank 1
P0420 Catalyst System below threshold - Bank 1
P04201 Exhaust Gas recirculation flow insuffcient detected

The last two it's been throwing for several years now, I simply haven't taken the time nor made the effort to address them.

However within the last two months the car has started cutting out during accelleration. It will stutter rapidly or sometimes slowly intermittedly when the vehicle is accellerating. Other times there are no symptoms at all (I'm pretty sure the first code is causing this).

I can get access to an ODB-II handheld at O'Reillys (how I diagnosed the codes in the first place). I just don't know what to look for to help dive into what the problem is, since it seems it could be a multitude of things. Any help or suggesstions would be appreciated. Thanks!

 

Focus on the EGR system code as it is likely causing the others.

Clean and scrape all of the carbon that is clogging the EGR chamber (ports and passages) and valve. This should fix the problem and codes, although the cat already may be dead.

 

http://www.tegger.com/hondafaq/egr-fix/index.html

 

So going after the O2 sensors, checking the manifold for leaks wouldn't be up first?