hi Iam new to the forum and not sure how things work. please forgive any mis postings. I have a 1994 Mazda 929 that I have owned for about five years. I just installed a transmission in it with 100,000 miles on it. In the process i installecd one new oxygen sensors. It was suppose to go on the driver side but my mechanic place it on the passenger side. Does anyone now how this may affect my cars performance???

Leonard

 

o2 sensors work like this. The perfect air/fuel ratio for combustion is 19.7 parts air and 1 part fuel. The o2 sensors job is to monitor this and report to the ECU so it can adjust timing/injector dwell etc. The o2 sensor does this by producing voltage. It's operating temperature is minmum of 700 degrees and generally does not operate lower than 2000 rpm. The o2 sensor switchs from rich to lean constantly to achieve this.Basicly driving down the highway the o2 will switch every 5-10 seconds. If it takes more than 10 seconds to switch it is deemed lazy and will cause a lean or rich code effecting performance. They can be monitored using a scan tool and holding the rpms at 2400 or so and watching them switch. If it takes 10 seconds or more to switch it needs to be replaced. However it is common for carbon to build up on o2 sensors and cause them to misread. Techron can sometimes clean them up.

 

Thanks for the info. I see that you have a lot of MECH. and Mazda knowledge. My mechanic decided to place my o2 sensor on the passenger side instead of the driver side. They have different product codes. Are they interchangeable and should have him replace it in its intended position???

Thanks again
Leonard

 

The o2 sensors are the same but the harness can be different lengths. You will need the o2 he took out in any event if the other is bad.