Chevrolet Repair: Chevy LT1, temp guage, metal flake

Question
Hello,
I have a 94 Formula with 90k miles on it.  The car has a squealing from what seems like the intake manifold area.  It pings like valve pinging and overheats, the exh manifolds got red hot today but the H20 temp gauge only read 210,but later dipped into the red after shutting off, and it was stumbling.  I started it up, and now it squeals louder.  There is no metal flake in the engine oil and don't think it is bearings. The car misses and pings on hills and loses power.  Any suggestions???

Answer
Hi JP,

I will explain what I think is happening and why.  

The pinging up hills is pre-ignition (spark knock).  That is when the gas in the cylinder fires off without the spark plug.  It is caused by the engine being too hot.  The power loss is because the strength of the power stroke is lost; when the mixture is ignited before the spark calls for it.  This is dangerous for your motor.  Can destroy valves and pistons.

Red hot manifolds is because the engine is too hot, and the fuel mixture is hotter than normal.  You are actually sending super hot exhaust out the exhaust valves.  This can warp valves, burn valves, destroy the manifolds, destroy the CAT, and other bad things.  

The temp guage is misreading because of low coolant or lack of coolant flow.  It is actually testing fumes, rather than the coolant itself.

The squealing is definately a pulley.  Which one?  Most likely the water pump is shot.  The squealing is the pump bearings.  No circulation.  

Disconnect the accessory belt, and turn the pump pulley by hand.  It is probably stuck, gritty, unable to turn freely.  Change the water pump.  It is expensive.  Also this is a great time to change the inevitable bad distributor.  

Good luck.  This could get pricey, even just for the parts.

C J S