by delbert brecht <halfsour@[EMAIL PROTECTED]
>
May 7, 2008 at 05:50 PM
techjohnny@[EMAIL PROTECTED]
> I spent several hundreds dollars to pass emissions last month. I was
> receiving eCU codes P0401 and P0420, which were both resolved after
> the shop replaced my Catalyst Converter and O2 sensor, but now the
> "Check Engine" light is back with the following codes:
>
> 0171 and 1456
>
> I knew something was wrong since the car had troubles accelerating
> after being at a complete stop. It will jerk and sometimes jump.
> I've never seen these two codes before having the shop work on my
> car. Could this be just a mere coincidence or should the shop help
> fix the problem?
>
> The Catalyst converter was after market.
>
> --tj
>
Would have been nice to have the year of the vehicle.
0401 code-Sound like the EGR system was acting up before. I assume you
have
an EGR system or you wouldn't have gotten the 0401 code. Ask the mechanic
that worked on it if he addressed that issue. Some on this newsgroup think
that a faulty EGR system will cause problems with the cat conv but I can't
confirm or deny that. 0420 is catalytic conv efficiency is low. That
should
have been corrected with the new cat.
0171 is fuel system too lean. Could be a LOT of different problems.
Plugged
fuel filter. MAP sensor. Primary O2 sensor. Bad fuel-drain tank and
refill.
Valve clearance incorrect. Exhaust leakage. Check for air leaks into the
intake manifold. Could be an oxygen sensor problem. A garage with good
diagnostic skills should be able to tell you. Perhaps the group will chime
in on this code with some more ideas.
1456 is a problem with the evap emissions control system. Start by making
sure the gas cap is on tight. Try a known good gas cap on it. After that
you
need some trouble shooting skills. There is a solenoid that controls
vacuum
to the purge canister to clean out the fuel fumes. Perhaps there is a leak
in that hose and when the solenoid opens it lets in raw air (thus the lean
mix) instead of the expected gas fumes (richer mix). Not much but a place
to
start.
--
Pickleman
halfsour@[EMAIL PROTECTED]
remove "yourpants" to reply
1998 Civic HX MT with 142K
2000 CRV EX MT with 98K
