So when I bought my Evo it had some ebay intake with a k&n filter on it, Hks Tbe and Injen intercooler piping.

I just installed the muse o2 housing with a new donut gasket and bolts

The car ran fine for 2 weeks then I installed a new Injen intake


now I am getting cels for p0134 and p0171.

When I drive my evo and come to a stop of take it out of gear the rpm's go way down to 400 to 600 and then come back up to 800-900 and it idles fine.

at idle my wideband is reading from 10 to 11.6 and you can smell its running rich.

I did a boost leak test today and nothing was leaking.

Please help!!!

 

Sounds like a bad O2 sensor, do you have a datalogging cable and evoscan?

 

yes i do

 

i guess in evoscan i dont know what to look for to see if its bad?

 

Interesting mix of codes P0134 is O2 sensor circuit no activity detected and P0171 is System Too Lean. My guess is something didn't get connected properly when you did the intake.
Check your MAF connector is plugged in, if you're using the MAF.
Check your connection to the front O2 sensor is OK.
Check all vacuum and boost lines are connected
Check the BOV connections are not leaking at intake pipe and top intercooler pipe
If all of the above is ok try disconnecting the battery for a while, check/reset base idle

 

i will try another reset in the morning and see what happens.

 

also when i went to get my copy of GTA V I plugged my laptop in and ran evoscan and logged both my o2 sensors and they are both reading..??? so wouldn't that mean the one in the o2 housing is working??

 

As long as the front O2 is showing readings in the 0.01 and 0.9 range, cycling up and down then it's probably OK. Unlikely the O2 has gone bad, it was OK before this intake install.

You didn't change your BOV when you did the intake? The BOV is installed the right way, in push configuration?

If you're really rich at idle you're most likely reading airflow at the MAF that isn't getting to the inlet manifold. The ECU thinks there's X amount of air arriving and injecting the corresponding amount of fuel, but if that air doesn't get there you're going to have a rich mix.

Is the filter on the Injen intake oiled? Could the MAF sensor have got dirty/oiled? Get some MAF cleaner and give it a clean.

 

Are you sure you used a diviorced gasket with the muse dump? Check the dump at idle and make sure no exhaust gas is coming outta the dump at idle, if it is, more than likely that is where your problem resides...

 

i had same codes and failed emission test.tuner turned that off and i passed.if you don't like the way car runs then yeah need to find the problem.

 

I did not change the blow off valve. i am using the perrin recirc valve.

I will try maf cleaner. is there a certain type i should use?

 

yes i am using a divorced gasket. and no i do not feel anything coming out the dump tube

 

A MAF cleaner like this http://crcindustries.com/ei/product_....aspx?id=05110