Replaced all but one elbow a few months ago, but could tell the most difficult would have to wait until I had the proper amount of time to devote to the project. Looked at the elbow yesterday and it was broken in two. I guess this would account for the 'check engine' light coming on and a rough idle.

Let me backtrack abit....originally, a code of 2-3-2 was given. The car just turned 160,000 and all rubber was original so after reading some posts, I decided to replace them all with the exception of the intake manifold. Cleared the codes.

Finally replaced the final elbow (I have scraped knuckles to prove it), and read the codes. 2-3-2 is gone, but now there is 4-4-3 (low efficiency cat. converter).

I realize that cats. only have a certain amount of life, but could a broken elbow have caused this reading? Especially since 2-3-2 is gone?

Thanks.

Dan