My 2000 Max GLE is exhibiting symptoms of a bad o2 sensor, well the symptoms are very common with everything else but what I'm thinking of is instead of replacing an o2 sensor, I'd just replace it with a sim because maybe later I'd like to run some performance upgrades and it might make things easier. I'm planning to replace the front o2 sensor (the one accessed through the engine bay), the rear one I don't know about because the cat looks rusty as hell and I don't really want to touch that yet.

Any thoughts?

 

Which symptoms are you experiencing?

 

Bad acceleration, running a little rich, bad mileage, whatever.. I thought it was the MAF but I replaced it twice, ****ty aftermarket bluestreak repurposed ones however... I got a new Hitachi MAF coming in the mail, if this doesn't fix my wagon then it's most likely the o2 sensor.

 

Any codes? Fuel trim data? You don't put simulators over the front O2 sensors monitoring fuel trim. Ever. Only the rear to get rid of a catalyst efficiency code. A catalytic converter efficiency code could mean the catalytic converter is getting blocked. Usually from long term oil consumption. That could make the engine bog down during acceleration.

 

I had a flex pipe replaced and got a high flow cat installed, mechanic tried to use a snap on tool to do idle air relearn for me and advance the ignition timing (it was fluctuating between 14-15 degrees so within spec) but the car ran like dog **** after because his snap on computer couldn't advancing the ignition timing and just shut down. I unplugged the battery for a bit and it's back to its usual self, at the very least it undid the snap on "tuning". Still stumbles a little and there's a delay in acceleration sometimes but I'm blaming that on the revolution sensor and the tb for now, I have both in the mail from eBay, as well as a Hitachi MAF.

The only code I have is P1440. I don't know what fuel trim data is or how to get it, but it was obviously running rich because I was getting horrible mileage and the car used to smell like gas all the time until the cat failed entirely, making it smell like rotten eggs as well. This is my first car and I've only had it for about a year now, I'm learning as I go along to stay ahead of the repairs so there's tons I don't know.

 

To be honest, a lot of the car's problems just went away when I replaced the catalytic converter and cleaned the revolution sensor and put it back in. O2 sensors are working fine, code reader finally said cat ready and o2 sensor ready which I've never seen before. I mean there's some more stuff but it's not related