
Originally Posted by
2rotor
now wait a second, ONLY at higher rpms? a leaking head gasket usually is obvious at lower rpms.
does the car lose coolant/water when you run it around, but is not obviously leaking?
a leaking headgasket can be a big repair, and shouldnt be hastily diagnosed.
does the car still have a catalytic converter? (if not this probably wont be relevant)
my 525 sat in the shop for a few weeks after i put a motor in it, i drove it today, and its putting out a little steam from the tailpipe, cleared up by the time i got home.
if the cooling system has some coolant in it, not just straight water, run the car until you can duplicate the smoke/steam and, here is the weird part, get a light wiff of it. if it has no smell, dont worry about it, drive the car through some heat cycles and see if it goes away. if it smells sweet / like coolant, then yeah, you are introducing coolant to the combustion chamber.
if the head gasket is leaking, the coolant is going to pump out pretty quickly, not slowly, if you want to do it that way, you need a pressure tester to look for compression pulses in the system.
lots of times i have seen perfectly healthy cars pump coolant out slowly with the cap off / car running.