Car idles badly for ca. 20 sec. right after starting (both cold & warm), and lately the coolant level indicator light goes on and off at times. MB dealer now says the headgasket leaks coolant into one of the cilinders. 1996 M111 engine has done 140K miles.

I'm looking at a repair of 1100 Euro.

Is it likely their diagnosis could be wrong?? My understanding is that headgasket probs on M111's are very very rare.


Thanks!

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2011 Prius