cisurfer

I used to always throw 1131 and 1151 codes until i got my tune from bama because of my longtubes, this past week i put my new trans in from hanlon motorsports and my front suspension (switch to upr)...today i threw 0133 and 0153, o2 slow response, i had the battery disconnected for 4 days while doing this work to it, today i unplugged the o2s and cleaned them off and plugged them back in...tonight i threw 0153, what is going on here, no wires are crimped or exposed sensors are less than a year old. the only different thing i have done is put my catted midpipe back on and to remove the trans i had to remove the passenger side header which i install tight, but the 0153 is the drivers side, any input? should i load my tune again?

uberstang1

No need to reload the tune because it donesn't just fall off the computer so to speak. Have you tried replacing the o2s at all?

cisurfer

they are both about 5 months old, for both to throw codes at the same time i highly doubt they are bad and are actually doing their job detecting an actually problem, what causes this to happen?

cisurfer

I swapped the o2 sensors from left to right. Cleared codes. P0153 came back. Only thing I did was replace transmission and added my catted midpipe instead of my offroad h

cliffyk

Exhaust leak(s) near the O2 sensor can cause those codes...

cisurfer

What about exhaust leaks like 2 inches after the sensor at the collector?

cisurfer

would having a tune for LT headers and o/r mid cause this to happen when putting a catted mid on?

cliffyk

I think that falls neatly into the "Exhaust leak(s) near the O2 sensor..." category.

It could, however the exhaust leak needs to be fixed first.

The exhaust flow is not one homogeneous stream, but rather a series of pulses created by each exhaust event. These pulses have a head, body, and tail; each with different characteristic, with their pressure relative to the outside world being the most significant.

• The head is at a pressure higher than ambient, when it passes the "leak" the gas flows out into the world; but the chemical composition of the gas in the pipe remains unchanged;
  
• The body is at or close to ambient pressure. When it passes the leak nothing happens as it and the ambient pressure are nearly the same--the chemical make-up of the gas in the pipe remains unchanged;
  
• The tail is at less than ambient pressure (nearly a complete vacuum), and when it passes by the leak it sucks in ambient air--changing the exhaust gas chemical composition and making it appear "leaner" to the O2 sensor;

This is why the leak makes the PCM believe the mix is lean, a big or close enough leak can cause the sensor response to slow or even appear "stuck".

cisurfer

ok there was a leak, which i fixed, ill try it again though, but like i said the only thing i did was change mid pipes really

cisurfer

i pulled the code again tonight, with new o2 sensors and got a p0133, if i have an exhaust leak how does it switch from side to side, one time its 0133 then the next its 0153