90 Oldsmobile Cutlass Supreme 3.1 Code 44

[crazyoildude]

i am trying to help someone with an oldsmobile cutlass supreme 3.1 engine has erratic idle and sometimes stalls also he says it smells rich from tail pipe.. He checked the obd1 with a paper clip and got code 44
So i told him sounds like an 02 sensor what does everyone think?

 

[beast3300]

Code 44: Oxygen sensor voltage was under 0.2 volts for at least 60 seconds of closed loop operation.

O2 is a possibility. I would check vacuum leaks that can cause lean conditions. I would also test fuel pressure.

 

[mechanicx]

Also clogged injectors can set a lean code. Even ignition misfire can because the O2 sensor measures air and a misfire will increase the oxygen level. That could explain why the guy smells gas but the O2 reads lean. You might try unpluging the EGR connecter and then the MAP to see what happens.

 

[Bob Woods]

A malfunctioning EGR valve can cause rough idle.

 

[CourierDriver]

90 percent of all o2 sensors sent back to the factory for warranty were not defective I read.

 

[OilNerd]

Had the same problem on my '89 Olds before. It was vacuum leak, in my case. Check the vacuum lines and check valve before replacing the O2 sensor.

 

[mechtech2]

An O2 sensor code can of course be an O2 sensor, but also from other problems.
Like a coolant sensor that failed, and the engine is running in open loop [rich].
Or a bad fuel injector.
Unfortunately, more digging is required.

 

[crazyoildude]

well the 02 sensor was replaced with a bosch and so far so good i will be sure in a couple of days..if i dont get a call before then