I have a 90 8V that idles smoothly most of the time, Lately it's developed hesitation at WOT only - Other than that it runs fine. Only problem is I recently found a coolant leak from the hot side of the radiator. New radiator ordered already.
Timing hasn't changed, Could use a tune up though. But then why would it only miss on WOT?
It's possible the o2 censor is bad. But wouldn't I get worse gas milage and be running rich too?
Is it possible a vacuum leak could cause this? If so - which line should I check?