02 sensor help

t1264rk

New member
Alright more 02 questions, I have a 99 buick lesabre with 3.8 no blower, under full throttle hardly any volts, also when u turn the key on, sensor doesn't heat up, I've checked wire connections, I've tried 4 used sensors, can't see them being all bad, at idle and holding the engine at 2000 rpm the sensor works good??????????????
 
Any other problems with car and is the engine light on what are the codes if it is, have you checked for proper Coolant Temp Sensor operation?
 
I'm lean bank 1, the temp sensor never reads rite I put a mechanical gauge in and the computer temp sensor is always 30 degrees off. But it. Is warming up enuff
 
I asked because when the Engine is cold the computer will be in an open loop rich mode and the o2 sensors arent running the show. Once the temp sensor sees the proper temp 150-170 deg depending, the o2 will begin to run the engine in a closed loop mode. If the coolant temp sensor never sees this temp the o2 wont operate properly you need a scanner that will monitor the ect volts when the engine is at normal operating temp the ect volts should be 1.0 or less at operating temp and close to 5 volts when cold. Lean could be a sign of an intake leak or some other vacuum leak start looking for those. Good Luck
 
I don't no why the temp sensor is off so much, I can't find any leaks, and still can't figure why the heating element in the 02 won't work
 
you can do a "bench check" of the temp sensor. read the resistance cold and the resistance hot or read it during warmup with a dmm look for the proper range and no jumps (degradation of the sensor) it is cheap enough, i would just put a new one in... it is rather old. that is where i would start. 30 degrees off is a lot.
 
Not really sure how to check those, the car doesn't run bad at part throttle, but the 02 voltAge is very low, it should be up around .800 to 900, I'm only gettn .030
 
Look around the lower intake between the cylinder heads, both the front and rear of the engine. Also might want to pressure test the cooling system.
Another guess is you may have an air pocket in the system. They need to be bled on the 3.1's and 3.4's.
 
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