I own a 95" cadillac sedan deville that has been

Cadillac Northstar owners to those whose vehicle is overheating .My 99 Deville was overheating turns out it was Catalytic Converter.Dont rely on PCM for code.If the Cat converter gets plugged up the heat will not get past converter it will back up into engine block causing overheating.My deville ran at between 190 & 201 degrees this morning.If you have a misfire the unburnt fuel goes into Converter and causes damage to converter (blockage).Alot of people overlook converter when overheating happens.

It might connect to the transmission, but I would be shocked if the wiring harness was the same.
A salvage yard should be able to tell you what will match up to the 95 model.

Hello: On the passenger side, Behind the glove box on top of the heater case is the Body control module, From underneath (passenger side) along side of the Programmer is the Engine control module. There is no one main ECU. This information applies to the sedan devilles with the 4.9 engine

The most common overheating problem with the Northstar engine is a blocked purge line(small hose).The purge line is designed to purge air out of the cooling system.
There is a small diameter hose coming from near the top of the coolant tank (not the cap) ,this is the purge line.
With the engine idling,pull the purge line from the tank,if there is no coolant flow from this small hose,it is blocked and this will cause overheating.
If the hose is clear, check for blockage at the nipple on the tank.Or trace the hose back until you find the blockage.
The hose goes in to the engine to a crossover and comes out the other side close to the thermostat housing,the blockage may be there.

They are bad to blow head gaskets.

Pretty dependable,but not cheap to repair when there is a problem.

Check the fluid.Change the fluid and filter and see if it gets better.If it does then I would recommend a fluid transfer.This will transfer the old fluid and add new fluid.Hope this helps.Good luck.

It sounds like they didn't get the cooling system filled completely, there's an air bubble. I had a problem with a 2000 Oldsmobile overheating, it turned out to be the aftermarket thermostat. I bought a stat from GM the problem went away.

Your radiator might have a clog and needs to be flushed...also check your water pump to see if its working right.

I'd start by tracing the fuel supply and return lines from the gas tank to the engine compartment. Make sure that they are free of kinks or other damage.

Next, check the fuse box and make sure there is power to the fuel pump. Trace the electrical connections leaving the fuel tank and make sure they weren't torn or otherwise damaged by the tire tread.

Hope this helps and good luck!