A head may warp if engine has been overheated badly. It may also be cracked internally. If overheat occurred best to have the head checked by a machine shop after it is removed. Associated with a warped head there will typically be leakage past the head gasket (blown head gasket). There is a whole set of symptoms and diagnostics for this.
You do not mention why you suspect warped head.

I had a hose dramatically burst a couple of weeks ago in the parking lot of circuit (jerk-it) city. It was the tiny hose that makes up part of the oil/water cooler off of the oil filter(92 B230FT). The hose was getting oil soaked from a valve cover leak that finally did the thing in. I was considering replacing the engine with a 94 B230FT, as this one has what I thought was piston slap (92 745TI w/ 108K bought it cheap from dealer who claimed rod knock but it goes away whne warm). Now that I finally got it all back together I think the slapping noise was actually 2 things, a crappy alt belt that is splapping and a hole in the exhaust manifold gasket (I could be wrong). The idle is pretty smooth (not perfect) but now I notice fresh coolant seeping through the headgasket. So my overheat blew the head gasket and maybe warped the head, it still drives like a champ.

You put a straight edge across its mating surface and measure underneath the edge with a feeler gauge. If the ends of the straight edge sit on the surface and there's a gap twixt the head and the straight edge in the middle then said head is warped.


Regards


Pete

So you need to pull the head? I am pretty stupid and have learned everything about cars as I go, trial and error make that a lot of error. - my father was a dead beat!

If you want to measure for warping yes.

However if the head is significantly wrped the head gasket will be blowing. Any decent shop will be able to test your engine for exhaust gases coming out through the coolant. They use a sniffer with a liquid in it that changes colour when exposed to exhaust gasses. No exhaust gasses in the coolant no warped head.Lot cheaper than pulling the head.


Regards


Pete

You need to do it in several different directions and also if
you can put a feeler gage under one end while holding the middle
down that is just as bad - bowed out rather than in.

Putting the straightedge diagonally will help tell if the head
is twisted.

0.002" is a good feeler gage to start with. Normally if a head
is warped no more than 2 thou in a 6" span you can pull it straight
with the headbolts (using a new headgasket).
--
George Downs, The "original" Walrus3, Bartlesville, Oklahoma

What have you tried so far?
--
George Downs, The "original" Walrus3, Bartlesville, Oklahoma

I haven't done anything so far since I have no idea what to do.