Hey all!

my CEL just came on and I got a code for a faulty o2 sensor. I’m looking at my options for replacing it and it looks like I have three options 2 Bosch after market types, one universal and another that seems to be exact fit. And of course the OEM, but it is significantly more expensive. I’ve read a few threads on here about replacing them and a few issues about the CEL coming back on with any other part than the OEM.

could anyone give me a rec for which one they used to replace theirs? I’m not unwilling to buy OEM, but I thought I’d see if I had another option.

thanks all!

 

Have you tested your O2 sensor? Have you erased the code and driven the car to see if it comes back? Is it a heater code or an indication the sensor signal is incorrect? For an 1989 what method to retrieve the code was used? (the flashing obd1 codes I trust) Or were you just going to replace it because you have a code?

I would clear and test and maybe even drive with it disconnected - an O2 on a 1989 does very little and replacement could be a sizable portion of what is car is valued at for some cars. Unless it's needed to pas an emission inspection where you live.

 

Older cars are less sensitive to the O2 sensor version or brand provided its the right design for your car. The hardest part is going to be getting the sensor out of the downpipe or cat. First thing is to make sure the fault code is truly the sensor. As noted, it could be a fault indicating an open or short circuit or it could be the lamba signal that controls fuel trim is out of range. The out of range signal could be due to an air leak or other issues. Also inspect the connection and wiring to make sure nothing got cut/frayed or corroded.

As to replacing the sensor, I've done the Bosch generic sensor on an 850T with good results (its the same sensor as OEM minus the model specific cabling/connector) - you just need to splice the sensor into the existing cable correctly (the kit comes with shrink wrap insulation). If you buy the full sensor, what you are getting is a new connector and the proper wiring length - so plug and play.

 

I got 221 on the flashing light diagnostic tool, which as I read on Trouble Codes means “Heated Oxygen Sensor(Rich mixture/part throttle).” and also 231 which means “Lambdfa adjustment”.

would the oxygen sensor be what’s at fault here then?

 

Have you erased the codes and driven the car to find out IF any codes come back? If not that would be the first step. Those are fuel trim codes with many possibilities and usually hard to solve because they can take a while to return (without just throwing parts at the car) The codes mean the control unit does not like the signals it's getting not that the part you are imagining is bad.

 

+1. O2 sensors always get cited as a possible cause for lean conditions when its just as likely that your 33 year old rubber bits are hard and crusty. Things like the rubber o-rings around the injectors, vacuum lines, intake air boots etc should all be inspected - you can spray some carb cleaner to see if any gets sucked in and bumps the idle etc or have a shop do a smoke test just to be sure. Also you can clean the throttle body and the idle air valve to make sure its not leaking air. Any other driveability issues??