No heat on 95 rmw

Shouldnt say no heat. If i let the car sit and run fir awhile, temp gauge will move up slightly and then heat works. If driven temp gauge drops to very low level and heat disappears. Thought it might be a thermostat  issue, so i went ahead and changed it. Same thing.

First think I would do is flush the heater core, first one way, then the other. Ninety nine percent of the time that is your problem.

Tom

How did the Dexkill look? I had to flush mine out with the thermostat removed at least 8 times before it ran clear. Garden hose at first, then distilled water with prestone radiator flush. I even used vinegar one flush. Came out great.
Had to forward & backflush the heater core with the garden hose. Clogged. Hard engine to do with the reverse flow & the subsequent air pocket that always forms. Exchanging the factory air nipple on the thermostat housing for a T-handle was a must for me.
Watch for freezing temps working with that water

Oh really important. Watch the opti with the bleeder valve, try not to get it wet. I ran a length of small vinyl tubing down from the brass t-handle fitting & zip tied it to the lower radiator hose. Makes bleeding the system so much easier.

Do not put Dexcool (orange / pink) back in the system....bad news!

Tom

My 96 RMW must have had a chemical cleaning before I got it. Had a new radiator and the Dex was very clean, but I hate Dex for all the things we have all heard and seen. When I went to get it all out, the knock sensors were very hard to get out, and when they did finally come out the were absolutely sfutffed with sludge. I dug out as much as I could and then put the garden hose in with the top with the thermostat out and full open mount do had water. Since I had gotten most of it loose, it appear, with the wire I had poked around with a bunch more came out. Did one guick run with water flush and drained again and filled with GO5. Must have worked because when I tore the engine down for rebuild a year ago every coolant passage was spotlessly clean.

The only way to get a good flush in these cars is to pull the sensors to drain all the coolant and any crud, I think.