Seems like a guessing game to me. I took my Volkswagen Jetta to them back at the end of December with a check engine light. They tightened a bolt and charged $300. Not even a week later the light came back on. So they decided it was something different. They changed a pipe $400. TWO DAYS later check engine light was on AGAIN. I was fed up at this point. They tried saying well maybe it could be this. WHY IN THE WORLD WOULD I LET THEM GUESS AGAIN WHEN THEY CHARGED ME OVER $700!! My car still isn't fixed!! Don't waste your money!!!