What are you using to determine that the spark timing is retarded (after TDC)? Is the scanner giving you a negative number?

 

Yes, with his scanner hooked up and reading and the motor at an idle, it displayed that the timing was at 12-17 degr. retarded, timing should be at 0 degr. (+ or -) 2 degrees.

 

Well, I am not sure what scanner you have or how it is telling you that the spark advance is retarded, but most scan tools list it as spark advance. Positive values are advance. Negative values are retarded.

And there is no set value for ignition timing. It is controlled by the PCM and is variable.

 

Your right it did say (-) which is retarded and some 20 degr. different than what your motor was running and I'm having power issues, stumbling, stalling, backfireing, hesitation. All this happens if you try to throttle moderately hard or harder. If you baby the throttle up it'll run smooth????
Sometimes you have to punch it Margeret, but I can't or it will fall flat.
I'm not calling you Margeret just making some light of it.