My acceleration problem was diagnosed as a bad oxygen sensor that works intermittently; performs better in warmer weather, however, there is slow, strained acceleration from a dead stop. Also, the mechanic said my plugs were fouled with oil. Any thoughts? Do you agree? Any suggestions? Regards, M

Well, replace your plugs with the CORRECT bosch H9DC0's. Compression check sounds like it's in order.

DO change plugs, and as you have the plugs out do a compression check,this can tell us if you have a bad valve or,If you do a leak down test we will know if you have good rings,The oil may indicate the need for valve stem seals, a much less expensive repair.JNT