Forget the E.C.U and concentrate on actual faults. By the description you gave, he will have done no more than replace some shagged electrolytics and possibly reworked some dry joints. There will having been no alterations to any code or anything in the I.C's. You seem to be suffering a coincidental problem, nothing more.
If the turnover is speeding up as you crank, check the batteries, related connections and starter motor. If those are fine, inspect and test the fuel system from the tank through to the injectors for leaks or restrictions.
If the turnover is speeding up as you crank, check the batteries, related connections and starter motor. If those are fine, inspect and test the fuel system from the tank through to the injectors for leaks or restrictions.
Comment