O2 Sensor? 99 Imp O/b Sport New Owner

[jonfit04]

Ok,

Again Another "cel" Issue. I Ran The Computer And It Gave Off A Code For Oxygen Sensor Malfunction, And Knock Sensor Malfunction. I Dont Understand Why It Gave Me The Knock Sensor Malfunction, B/c I Just Tried To Replace The Sensor...when I Did The Car Ran Like Horse Sh*t. It Would Mis And Carry-on, Would Not Run At All...so I Took The New Sensor Off And Cleaned The Block And Old Sensor...put It Back On And The Car Ran Fine....now I Get The Cel And It Gives Me O2 Sensor.....i Quess What My Question Is, Does A 1999 Imp O/b Sport Have 1 Or 2 Sensors...i Looked Quickly Under The Car This Morning And I Seen One At The Cat Converter. Also The Car Is Doing Pretty Much The Same Thing It Did When The Knock Senor Caused The Cel...it Would Drive Fine And Then All Of A Sudden Start To Hesitate And Then The Rpm's Would Drop And Go Into "limp Home Mode"...still Run, But Would Not Go Very Fast For A Few Moments And Then Go Back To Normal. So Here's What I Am Thinking To Do. I Am Going To Call A Mechaninic And Have The O2 And Knock Sensor Changed At The Same Time...the Car Has 192000 Mile On It, Dont Know Weather Or Not It Was Ever Changed.....before I Do, Just Would Like To Know If This Is Something I Could Possibly Do, Or If It Something That Should Be Left Up To Professionals?

 

Thanks

Jon

[Wayne Boncyk]

O2 and Knock sensors are both pretty easy to change if you've got some mechanical experience, the tools needed, and some time. The O2 sensors will be more difficult than the Knock sensor, since they're in the path of hot exhaust gases and that causes them to get stuck in their flanges. Expect to spend some time waiting for a penetrating oil (like PB Blaster or similar) to help to free them up. You should have 2 O2 sensors on that vehicle, right? One at the front of the Cat, and one at the Cat output to the exhaust pipe.

 

Sounds to me that you may need more than just sensors -- just because the OBD codes tell you that something isn't right with them doesn't mean that the sensor has necessarily failed. From what you're describing, I would guess that your timing is off a bit, too. Perhaps the timing belt has jumped a tooth. Just a guess -- but unless you do a little more detective work, all we can do is guess.