My 2006 h3 wouldn't start in -5 temperature--it did start, I drove it to the hotel entrance, turned it off to collect my luggage and wouldn't start.
I work in Minnesota since Jan 2022 and it always started in minus weather, down to minus 36.

Anyway, it would not start while traveling and I had it towed to GMC dealer, they diagnosed it as 2 cylinders with zero compression.
I live 500 miles away, drove over and towed it home. Battery was dead so I put jumpers on it to put H3 into neutral to off load. Decided
to try and start it, and it started right up and runs fine. Contacted GMC services and they claimed in cold weather valves stick and
creates no compression and H3 won't start. This really doesn't seem legit--but I could be wrong, that's why I am asking here...

Their first suggestion was them finding a used engine and replacing mine at $ 175 per hour / 19.1 hours.....

Is this possible? and if so how to prevent as this was costly .

I did search but didn't find another post, apologies if I missed it.

Thanks

 

Indeed the valves stick, due to carbon buildup. Try some SeaFoam,works for me!