[mek42]

I recently (~6 weeks ago) had my throttle body cleaned while I had my alternator and battery replaced (we're looking for a third vehicle so that we can have one off the road waiting for parts in the future) and after these services the Echo ran very rough. We complained before leaving the parking lot and were told that the roughness was normal due to the computer resetting from the battery change.

About 3 weeks ago we started having power loss issues. The end result is that last night I put some Chevron Techron in and drove the Echo a bit and significant improvement seems to have been made. (FWIW a Seafoam gas tank treatment last week did not help the problem - I am now a Tachron believer.)

For future reference, I am trying to understand what happened. Could dirt / carbon crud from the throttle body have migrated into the fuel injectors causing a clog?

As far as codes, there has been an ongoing P0171 lean and 440, 441 and 446 EVAP codes that my dealership say is due to the charcoal cannister - I was planning to save up and replace that this summer. (Unless the issue is just the gas overfill valve - we also have issues putting gas in the vehicle - and the OVRV is a seperately replaceable part as opposed to the entire charcoal cannister.) After getting the vehicle back from the initial throttle body cleaning service, there has also been a P0420 catalytic converter code and a oxygen sensor heating element code (I forget the P number and bank for this). Could the oxygen sensor failure be giving the 420? Would taking it in for an exhaust analysis indicate whether the cat is bad?

The Echo currently has 235K miles and I'm trying to figure out whether it is time to give up the ghost or not.