Thanks.

I get my code reader back today so I think my plan will be:
1) Confirm, consistent with last time I read the codes, that I am only getting ones related to the fuel temp sensor and the O2 sensors.
2) If the above, is true, I will pull the sensors noted in the codes and test the sensors (the blow torch/multimeter method I think should work for the O2 ...)
3) Replace any sensors that don't appear to be working.
4) Reinstall. Reset codes. Drive for a couple weeks and see if they come back.

On a related note - anyone have an extra fuel temp sensor lying around? I would like to avoid the $100+ price they seem to go for if possible.

 

Don't get too ahead of yourself. Find a scanner, plug it in, record data provided and go from there. Removing those o2 sensors isn't the easiest task. Access to the plugs is tough to say the least. Your plan should be to replace them if the data you get from the scanner indicates they're not operating correctly.

 

Exactly. That was step 1 - "confirm the O2 sensors are throwing codes as I expect". I could have said check the O2 sensor to see if they were throwing codes but the step would be the same, just my expectation wouldn't be in there ....

I agree though - the one thing I have learned is that whenever something sounds like it will be straight forward, it usual is not.

 

Checked the codes -

Only 1 right now: P1179 Maximum Negative AMFR Correction Fault

Haven't had this one before ....

Also, the readiness monitor said the Cat checks are not done yet so I will put some more miles on it I guess and see if that one fixes?

 

That is a MAF code, clean it and put it back, clear the code and see what happens.

 

Will give that a try. Do you think that could have, alone, caused my extremely high emissions?

Do you think I should do it first or wait for the cat testing cycle to finish first to see if I have other codes? I was just thinking - if I reset, I need to wait another 8 or 9 cycles to see if there are any further problems? Thoughts?

 

Yes that can cause your emissions to fail.
Since you are trying to complete a drive cycle just clean the MAF, make sure you plug it back in, I've forgotten before and drove to work that way.
Make sure you use MAF Cleaner and follow the directions.

 

Thanks, will do.

Should I just spray it all over with the MAF cleaner? Do I need to remove it from the intake tubing?

 

You spray the inside, when engine is stone cold. You don't want themal shock on the sensor. Take one end or both ends loose. May spin a few revolutions to crank up, because you will have fluid in the intake plumbing.

Do not turn on truck before you spray. Just powering up the truck to position 2 makes a tiny part inside the MAF warm up to 350 F above ambient. And have you priced a replacement MAF? Some guys paid less for their truck.

 

Yes you remove it from the intake tubing, set it on the bench or driveway whatever.
Clean the whole thing, until the cleaner comes out clean or the can is empty.
Let it dry, put it back.