I have a '94 z28. As i'm driving ahnd the car is still cool, it runs good. As the car warms up, it has come close to the last white line before the red for the temp. I have a water pump i bought from jason cromer installed last year. I had a 160 thermostat in there. I also had a new or rebuilt radiator installed last year. The car used to never get past 190. Now i come close to the red, but never touch it, it starts cooling off a little then goes up again. Then the car starts bogging bad and backfiring to the point where i have to pull over and let the car sit for a while and cool off to drive it again, cause when i gave it gas, i was barely going 10 mph. What i noticed the other day is, i was in the garage, i put the a/c on max, and i could hear the fans come on, but they keep coming on and off, never stay on steady, is this normal? I haven't had a coolant flush for a long time. I'm changing the plugs and wires and thinking of changing the o2's cause i think i had a code for the o2's come on earlier in the year, plus i have gone through 2-3 random tech high flow cat's, where there was nothing left inside them, cause i was running really rich, the guy at the muffler shop asked me if i had them hollowed out, which i didn't do. Sorry if this is to long, just need some answers.

 

Have you tried bleeding the air out of the system? This could cause your temp to get up there.

 

no, haven't done it yet.