Determining if O2 sensor is closed loop or open loop

pippo

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People,

As you may know from so many posts here about my O2 sensor problems I am trying to trouble shoot O2 sensor trouble codes- mainly 13 (open loop/lean), and even sometimes 45 (rich fuel). One Shop manualm tree diagram specifies if scan shows open loop circuit. How does one determine that? Does one need a GM scanner/scan tool?

I am going through so many new O2 sensors- name brand as well as cheaper brands- none survive more than 1-2 weeks.
 
You really need to find a shop with OBD1 scanner or buy the Moates setup on eBay that lets you see the readings on a laptop..

More likely you need new valve seals.... or rings......

Have you tried thicker oil or STP ? I run both down here, cuts oil consumption down...

Doug in P.R.😎
 
Thanks, Doug. So, I am willing to try "thicker oil". I am using currently the recommended 5w30. What would you try if you had my problem? 10w40? Higher? Straight 40W oil? Or what STP product can I add to the current oil in my engine, this:


I am encouraged by your experience in having used this thicker oil without major problems, I figure.
 
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I always use 10w40 blended brands with STP ( same in your picture) down here, it's too hot for that thin stuff, it uses only 3/4 of a quart every oil change...(3000 miles)

All 4 seasons too.

Never changed the O2 either 139k -158K miles( not sure of the previous owner)

Doug in P.R.😎
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New ECM arriving tomorrow. Will see if that fixes the problem. Tried everything else. Low risk, to keep the car running! Remember- I have 233,000 miles on it. Like an 80 year old man. 10 years left before it dies.
 
The new "reman'd" ECM proved to be junk. The speedometer and tach didnt even function with that ecm. Im returning it at their expense! Junk!
Car ran great for 30 miles with a new O2 sensor, but code 13 showed up again. Gonna ask a local mech I know if he has an OBD1 scan tool. Im almost at the end, people.
PS: Added STP, but didn help much. No regrets though, as I believe that could only help. Just wanted to post my results.
 
That's about average miles I've seen in junkyards on 2.0's......everything else is a bonus....👍


Doug in P.R.😎

Right! Thats where one would find them- in the junk yard at over/near 2K, but mine is omne the road still........LOL. Who has a s'bird with over 234,000 (now) miles? Anyway, there are just a few of is left here, as endangered species. Looking out for each other, at least!!
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