my 2003 barely has power now. i replaced o2 sensor in bank one sensor one per code P0131. i then replaced a vacuum hose that had been damaged as well. i got P0404 and then it disappeared it seems after i replaced the vacuum hose and did some other work as follows..

after replacing o2 sensor and vacuum hose. i also replaced all spark plugs and spark plug wires as well.did the oil and oil filter..

i did look at and smell the transmission fluid, its red and doesnt stink though i dont know filter shape.

this has been going on for about 4 days now.currently there are no codes popping up and to see if they disappeared on their on.i left battery plugged in.

im uncertain what else to look at...is there a break in period so the computer can readjust as well? or any idea what to look at or could be the cause.

even when shifting it doesnt seem to want to shift properly and rpm has to be kinda high at times depending on gears mostly.especially after driving on road a few mins.

 

update: i went and added some gas to the tank as it was low and now the car seems to perform better..shifts better and has a little more power...pump issues?

 

update 2: just took it out for a test drive again. car does have some power but had a couple times where it lacked power like before.almost seems that turning may give it alittle more power..could be me though.engine revs up just fine in park.

 

Might have a plugged up cat... Especially if it runs fine while cold

 

thats exactly what i and a few others i just yalked to at work said..and with you,that pretty much confirms it will probably hollow it out and try it to see what happens.if thats it for sure.will be replacing asap.. thank you

 

A scan tool that reads live sensor data is much more helpful at diagnosing issues beyond just a code reader. Well worth the investment working in modern cars.

 

that would be great..unfortunately i dont have the money for one rite now.thogh i learned something new avout my car..i may post it in new post for the time being...when i go the car has a loss of power.if i let go of the gas and press again some power comes back.it does that several times between gears and can pixk up speed a little better compared to just keeping foot on gas.i thought maybe egr valve since i did get a p0404 code the other day and it went away after fixing a broken vacuum tube.but i still bet on the cat..any videos or tuts to remove cat from the car?

 

I hear that a lot on the forums. They're really one of those tools that pays for themselves. The alternatives:
-Shotgunning parts at it based on guessing, wastes money by replacing good parts.
-Wasting time trying to figure out other ways to diagnose issues. Wastes hours of your time, worse especially when combined with the above.
-Eventually breaking down and paying a shop to fix issues you cant figure out. Even 1 hour of tech time pays for a scan tool.

As with the above, there is a proper way to diagnose a plugged cat before you start destroying it based on a guess. Even cheaper than a scan tool, it just requires one of those IR temp guns, which can be had for like $10 nowadays.

Removing the cat itself isnt possible without cutting it out. You need to remove the whole downpipe. Its pretty simple to remove - 2 bolts on each end plus the wire harness for the rear O2.

 

my wife and i just spent nearly what we had as we are moving into a house on August 1st.just keeping money in my account at the time to make sure all goes smoothly..i will be investing in one when we move into there.i dont know how many times i worked on my vehicles and needed one.in fact i have my rv to fix though i already know whats wrong with it.

it was in fact the cat.got it taken care of and the car has more power than ever.besides the fact it did need everything else i put in it..will be replacing other o2 sensor later on and a few other parts as well oh i have a borescope so i dont need to cut anything to see inside the pipe.i have the pics of the cat now.roughly 3/4 clogged.

 

Glad to hear you got it fixed!