I have a '94 z28. This summer, the temperature gauge has been getting too high too fast. It also bogs a lot at low rpms when it gets hot. The car only has 37k miles on it. I changed thermostat. I didn't think it would be the water pump because of the low miles. Any ideas. i've hear these cars just run hot. true?

 

Are the fans running when it gets hot? Check engine lite lit? Air dam under radiator still there? Purged allthe air out of cooling system?

 

fans work. air dam check. no check engine light. filled coolant until it ran out of the overflow valves. i'm thinking i need to get a hypertech 3 and a 160 thermostat. any other ideas? also, i did see some fog on my windshield. maybe radiator core?

 

Try the last option Pete suggested. You may have air in your coolant system. I flushed my radiator and noticed afterward that my car ran hotter than it did before I flushed it so I knew I had air in the system. In my case all I had to do was run the car until it was at about 180-200 degrees. Next you'll notice 2 screws on the water hoses just above your water pump. Use a screwdriver to open them and you should notice air coming out. I did that until I noticed coolant coming out and then closed them up. Made a huge difference and my car runs cool. Only takes a few minutes and doesn't cost a thing.

 

Nevermind! I didn't read your last post correctly! You already did the overflow valves!! I hate it when that happends!!!

 

OK then! These cars are designed to run hot. The fans are set to come on a 225 deg (low speed or primary) and at 232 deg (high speed or primary + secondary). So in slow traffic the temp will hover between 225 & 240 degrees. However; on fast highway travel the temp should drop down to under 200 deg. The high temp bogging is a pretty common problem, usually due to ignition or a bad sensor. Run the car with the MAF unplugged & see if the bogging stops. (don't worry about the SES lite). If it runs better you have a sensor problem, and will need a scan tool to identify which one.

 

thanks for the help. i'll let you guys know when i figure it out