1988 mazda rx7 fc3s s4 n/a manual trans 2nd engine since ~145,000 miles and is now ~254,000 miles

Hello again friends, about a month ago I had to do the gasket on my water pump (both sides), and all was well. Between then and now, I replaced my mufflers to fix the exhaust leak I've always had, installed used Cusco struts, replaced a bent control arm, alignment, and had an oil change. But lately I've noticed a burning smell once I get on the highway, my coolant temp meter slowly climb the longer I drive the vehicle (after letting it warm up a bit of course). It also seems to sputter when warming up quite a bit before the exhaust sounds like it normally should; it's a very deep bass.

However, it used to only do that in the spring, when it starts to get warm, and in the fall, when it starts to get cold. during the summer or winter, it did no such thing.

 

Did you also replace your thermostat? Does the car have a/c? Or did have a/c? The condensor in front of the radiator loves to get packed full of leaves and other crap and restricts airflow alot for the radiator

 

I have replaced the thermostat before but that was a little over a year ago. I actually took off the belt for my a/c. What happened was when I was reassembling the water pump, I had the a/c belt looped around the wrong pulley on the harmonic balancer. I was at work and we were closing and I didn't have time to fix that so I cut the belt off. Not a favorable thing to do, but the car wasn't producing cold air in the first place so I left it alone since that water pump fix.