New O2 sensors k-1500

[Sutty]

Hello, I just rolled 200K in my truck and my truck's check engine lite came on with a p0161 which is a passenger side heat coil failure on the o2 sensor after the cat. Might be because I just ran some sea foam through but since they are still the original ones I thought it might be a good time to change them all anyway. So I started looking into it and the parts depend on which transmission I have which I thought was weird??? 4L80 or 4L60E. How can I tell which one I have call the dealer with my vin?

Oh its a 98 GMC K-1500

[jwhjr]

You can check the RPO Code in the glove box. If you see a M30 you have the 4L60E.

[Jeremy airjer W]

O2 sensors have two circuits and four wires. One circuit is the actual sensor the other is the heater. The sensor needs to be hot to work, the heater speeds up the process. If the code is for the heater circuit there are two possibilities depending on how the heaters are fused. Either the heater has failed which will require the replacement of the O2 sensor or the fuse has failed which could be linked to a bad heater or bad wiring or sunspots (a little humor for you - sometimes there is no logical reason for the blown fuses and a new one takes care of the problem). I would have to look at a wiring diagram to see specifically how the heaters are powered up on your particular vehicle. It wouldn't hurt to just check them quick.

We just had a blazer in the shop the other day. The customer had replaced the O2 sensor because the code he had said the heater circuit had failed. It ended up being a blown fuse. Since the O2 had already been replaced we weren't able to confirm that the O2 was the problem.

[Shack]

I will also agree, check the fuses. It is rare, but cost's nothing.

I have seen O-2's fail after an induction clean or some other treatment. Replace the one(s) that are needed. There is no service interval on O-2's. If they work, they work.

Good luck..

[Sutty]

OK thanks for the tips, I'll check for a blown fuse first.