I did double check every thing I touched during the oil change execpt the knock sensors because I didn't know where they were. I will check them tonight or sunday. The reason I am so "helpless" is the fact that the first cars wiring was shoddy at best. For all I know the CEL didn't even work so CEL NEVER came on. The second car was just a parts car so I never drove it. This is the best working car I have owned so I'm encountering alot of new problems that were either: not there in my previous Supra or I had no way of knowing until something catastrophic happend.