Replaced O2 sensors and now… (1 Viewer)

[UGA2018]

My sons 96 80 series had the check engine light come on. I got codes PO130 and PO133. So I replaced the O2 sensors with Densos. The old ones were pretty crusty and looked like they never had been replaced.

However, I still have those 2 codes and now I’m also getting PO171.

Thoughts on what to chase next? Thanks!!

 

[cahill]

Maybe check the air intake to make sure there isn't any leak/unmetered air? The rubber intake tube can have some cracks that develop and can be hard to notice/find in the valleys of the ridged portion of the intake tube. Also it may be that the computer needs to re-adjust to the new inputs from the sensors. Running a diagnostic to see what the fuel trim is doing and what the oxygen sensors are sending to the ECU can be helpful. I have heard of people putting in new o2 sensors and having one of them being bad despite being new.

 

[JoeW]

171 is a lean code. Time to get a smoke machine and make sure your intake is free of vacuum leaks. Also if this is coming up after swapping the sensors, are they sealing correctly on the exhaust?

 

[BILT4ME]

Did you clear your codes after changing sensors?

 

[UGA2018]

Did you clear your codes after changing sensors?

Well… I unhooked the battery terminal and then reconnected and now no engine check light. Should I consider the problem solved?

 

[BILT4ME]

Well… I unhooked the battery terminal and then reconnected and now no engine check light. Should I consider the problem solved?

Yes, but you just said you had codes.

If you're still getting codes, then they need to be addressed.

Codes can be set without having the CEL on full time. It depends on the type of code set.

 

[UGA2018]

Yes, but you just said you had codes.

If you're still getting codes, then they need to be addressed.

Codes can be set without having the CEL on full time. It depends on the type of code set.

I’m not getting any codes now. I got codes after I replaced the O2 sensors but before I disconnected the battery. Now I’m not getting the CEL or codes with my reader.

 

[BILT4ME]

I’m not getting any codes now. I got codes after I replaced the O2 sensors but before I disconnected the battery. Now I’m not getting the CEL or codes with my reader.

Then you should be good until you get another one!

Fix it until it's broke!