ringram
March 21st, 2006, 10:46 PM
Ok, Ive been helping a guy with a case of a bad install.
Basically a shop installed headers with no o2 bungs, so mounted them post cat.
o2 switchpoints were well into the 500mv range and not surprisingly the vehicle failed emissions.
Ive advised him to relocate the sensors, but in the meantime we tried altering o2 switchpoints a little.
The vehicle now reports lambda 1.026 so a tiny bit lean, HC is now well down limit is 200ppm count is like 14ppm or something.
Problem is CO is well high, but thats werid because its running bang on or slightly lean. So what gives?
Also he thinks there might be a small exhaust leak.
Anyway plan is to try open loop, but preferably to get the O2 bungs in the collectors installed and relocate O2 and fix leak.
Just wondering if anyone had any thoughts on why CO is high but HC and Lambda is good.
Basically a shop installed headers with no o2 bungs, so mounted them post cat.
o2 switchpoints were well into the 500mv range and not surprisingly the vehicle failed emissions.
Ive advised him to relocate the sensors, but in the meantime we tried altering o2 switchpoints a little.
The vehicle now reports lambda 1.026 so a tiny bit lean, HC is now well down limit is 200ppm count is like 14ppm or something.
Problem is CO is well high, but thats werid because its running bang on or slightly lean. So what gives?
Also he thinks there might be a small exhaust leak.
Anyway plan is to try open loop, but preferably to get the O2 bungs in the collectors installed and relocate O2 and fix leak.
Just wondering if anyone had any thoughts on why CO is high but HC and Lambda is good.