Hey Jim,
Just saw this thread and wanted to respond with a big "Thank you". This information is definitely worth reading and holding on to!! Now I get it!!
BTW, I finally had some time to finish the install of my pre-cats last night. Talk about a small work space!! I ended up buying a ten dollar 3/8" dr. with a flex head ratchet handle to start and finish the job. I didn't need this tool for the post-cats, but realized it's effectiveness very quickly! This was one time where I was glad that I got what I paid for!!
Before I found this nifty tool I thought I would have to take down the exhaust or worse yet, go to my mechanic and be charged up the &%^ just for labor. Anyway, I am definitely very happy!! And with a new understanding of how these sensors work,....even better!!
...So, Randall --now I know what you mean about a big change in performance after changing all four sensors!!! My car never sounded so good ----just wonderful!! Thanks for your input regarding the sensor change. I know I will probably need to purchase a new MAF down the road ---but so far, so good! :dance: