I have a 92 RS with the 305 and 5-speed. It has a problem with heating up when not actually moving and at higher rpms. When crusing at 60 to 70 in 5th gear it rests right at 160 but if I get on the gas for extended periods or if I am driving really slow or at stop signs the temp creeps up to the 220 and even 240 marks.

I have already checked to make sure the fan is working and there is no debris in front of the radiator and between the radiator and the condensor core. I have installed a new 160 thermostat and was about to install a new water pump too but the one I have seems to work fine (when I had the thermostat out I spun it by hand and it flooded the top of the intake).

Does anyone out there have any other ideas?

 

is the air damn in place?

 

Yes. I should have stated but that has been checked.

 

Well, Im gonna throw out what I always say...........your radiator is 19 years old. My 82 did the SAME thing....got hot (210-220) after a WOT highway run or during long periods of stop and go or real slow traffic. I tried all the common cures, lower thermostat, checked for cavitation, even considered a high volume water pump. I even put on header wrap (bad mistake) and it didnt get any better. Well, this winter I replaced my radiator while i was doing several other upgrades and she hasn't gone past 190 since. She now cruises at about 175 degrees all day long. Rarely will she go above 180.

Im telling ya, people underestimate the amount of crap that builds up in a radiator over time that dramatically compromises its performance. Once its in there, its there for good and a flush wont get it out. Spend the money on a radiator. I got mine for 100 bucks at NAPA. Im bettin dollars to donuts it fixes your problem.

 

^^^ there you are. sounds like scottd has it. donuts,,, where?