Alright, I've got a coolant leak from the back of the motor somewhere. I've got a 2005 G35 sedan and I had a new motor installed under warranty by the dealership here about 3000 miles ago. In the last couple of weeks, I constantly smell coolant and the other day I was sitting in traffic for about 30 minutes on one of our wonderful 100 degree days here in Nashville and noticed the needle start inchin up. I finally got to where I was goin and cut the car off and a few minutes later coolant came pouring out of something on the back of the motor. I let it cool and refilled it. THEN on the way in to work this morning I was driving along, looked down and the needle's pegged at H! Immediately pulled over, cut the car and popped the hood. No pouring coolant this time but maybe a slight drip if anything. Drove to work with the A/C off and the needle kept slowly moving from the middle to H and back again randomly. Anybody have a clue what's goin on here? I couldn't see where on the motor the coolant's comin from. Of course there's not a whole lot of room in there to begin with. HELP!!!! Thanks!

 

Dang that sux...If still under warranty take back to dealer. If not I think its either a hose that is riped

 

Take off your engine cover and take a look at the hoses to make sure they all are snug and in good shape. I would think the dealership would have used new hoses when putting in a motor because it's easy to do and probably able to write off as warranty work. There's a air relief screw in the hose to the right of the battery compartment that's used to burp the coolant system. Maybe they forgot to put it back on or it worked it's way loose. Either way, the dealership should fix this for u.