Engine oil flush

I just recently had and engine flush with my oil change and an independent garage. Now my check engine light has come on. I talked to someone who told me that here mazda does the same thing when she gets an engine flush thats not done at the dealers, and that i shouldn't worry about it. Has anybody had the same experience.

John

not possible with Isuzu
double check your fuel cap make sure it is properly installed
most common thing is that or EGR valve sticking