CEL - help, any ideas

[VictorH]

I'm getting a "Lambda probe heating system diagnostics" code on my car by iCarly says the code is 002740.

I had a similar code but maybe with a B in front of it a few months ago, replaced the pre-cat O2 sensor on the side indicated and that fixed the issue. Since the other O2 sensor was the same age, I replaced that pre-cat O2 sensor as well, so they are both less than 10,000 miles old.

Any ideas what this is? If it's a faulty sensor why doesn't it way which one? If it's something else then would be nice to know so I can fix it. Appreciate anyone's insight.

[8600RPM]

I had this problem over and over until finally my ICV popped up. If youve,changed the sensor and still get it pop up it can be,early sign of icv

[BPMSport]

2740:
Oxygen sensor heating control diagnosis before catalytic converter, bank 1
Fault description: O2 Sensor Temperature Measurement Operating
Temperature not Reached (Bank 1 Sensor 1)

Check the plug and wiring on that sensor. If OK, clear the codes. If it comes back, I would replace that sensor. Perhaps you have a faulty one from the factory or something else is going on.

[vsix]

Connections of the o2 sensors came loose.Clear codes, inspect mentioned

[JEllis]

Also, sometimes O2 sensors get twisted up badly by installers that do not understand what they are doing. The sensor should be screwed down with the associated wiring and plug disconnected so it does not get twisted up.

[VictorH]

Appreciate the responses. I'm the mechanic, but generally I'm pretty diligent about this stuff. I had to disconnect both oxygen sensors when I changed my rod bearings in December so maybe there's something to it. Odd that it takes two months to show up but stranger things have happened.

Should not be related but I just changed my power steering return line (to the reservoir), and started and stopped my engine 3-4 times (first time turns out I hadn't completely snapped the connector to the PS cooler (the bottom fitting) and it blew off leaving a mess everywhere. Took everything apart again and cleaned it all and put it back together. Next AM on way to work, get the CEL. I think it's just a coincidence and annoying but what can you do.

[VictorH]

Follow up. Mike was right again.
Short story
1) Same message comes back after clearing but then get "failure detection cylinder #6."
2) Both O2 sensors had been replaced in the past 6,000 miles (late last fall)
3) Replace O2 sensor (pre-cat) on bank 2 (because of the cylinder #6 issue code)
4) Error code comes right back
5) Switch new O2 sensor to bank #1 and code is gone (so is the cylinder #6 code).

Odd to have new O2 sensor only last a few thousand miles but I'm back in business now. Thanks for the advice and help.

[OneSickM]

Originally Posted by VictorH

Follow up. Mike was right again.
Short story
1) Same message comes back after clearing but then get "failure detection cylinder #6."
2) Both O2 sensors had been replaced in the past 6,000 miles (late last fall)
3) Replace O2 sensor (pre-cat) on bank 2 (because of the cylinder #6 issue code)
4) Error code comes right back
5) Switch new O2 sensor to bank #1 and code is gone (so is the cylinder #6 code).

Odd to have new O2 sensor only last a few thousand miles but I'm back in business now. Thanks for the advice and help.

supercharged?

[dparm]

O2 sensors have a finite life. I doubt it's related to your rod bearing work.