Hi guys my farther in law has a 2002 wrx it has stainless headers,turbo back 3" system,ecutek, aps tmic

Basically when the engine is hot or even after a 50 mile run when behind him steam like vapor can be seen when pulling off or when reved(or say it was winter that kind of vapor when it's cold) it still did it when we had the mini heat wave at 28degree's!, it also spits water out of the exhaust??
There is no actual loss in the coolent so what could be causing this?? We thought maybe water running into the back box and collecting there but surely it should clear with heat and been run daily??
Another person has said it is because of stainless headers??
Any help or advice would be grateful

 

It can take a good while for the back box to get hot enough to evaporate all the moisture. It can depend how far it is run daily and the manner it's driven in. I try to get a few high rev runs when I go out so the exhaust gases can blow any moisture out. Should be fun in the next couple of weeks as the car has not been on the road for 6 months might give a car behind me a quick wash.

 

Yeah it has had some high revs, maybe tell him give it a few high rev runs for a week see how it go's