joedrum71

I bought my 98 Z28 totaled and rebuilt it. No serious damage to the radiator, just a ding in a few of the fins. I drive on the highway to work, temp seems normal. But if I do just city driving, it seems a bit high. I had stopped at my parents house the other night (after coming back from a 15 mile highway trip) and left the car running for about 10 minutes and noticed it was sitting at about 240-250. Is that normal or high? As soon as I left, it dropped a bit. Do I replace the thermostat, coolant?.?.?.?. When do the fan's kick in? I would put a 160 deg. thermostat in, but it doesn't pay without reprogramming the fans. I've also seen where there is air in the system and can cause overheating. If so, what's the best way to get the air out?? Do you guy's also recommend a 50/50 mix with the coolant? Any help or ideas would be great. Thanks.

Joe

Ferocity02

iTrader: (60)

Thats normal, since there is no air moving through the radiator in city drving, the temp will go up. 160 thermo will not help much or at all.

TA TED

Mine runs around 210 in the summer while in light stop and go traffic. Fans on low speed come on @228, fans on hi@235. Temp should immediately come down when the fans come on.

joedrum71

My fans aren't even kicking on.

foff667

iTrader: (2)

id autotap it to see what temps its actually seeing...anything over id say 235 is kinda abnormal...with programming, 160 stat, heads/cam mine wont go over 190 according to autotap now well at least in the 80 degree weather weve had lately so take that for what its worth...before it would go up to maybe 230 while sitting in the staging lanes at the track.

TA TED

The PCM monitors the coolant temp sensor in the drivers head and then initiates the cycles of the fans. I would think that even if your thermo is partially stuck closed and not letting the coolant travel to the radiator, the sensor is still talking to the PCM and it should turn on the fans. Check your sensor, all wiring, connectors, and the cooling fan relays. If you need to isolate the circuits, the relays are a great place to do it. Assuming you have a wiring diagram, pull the relays and jump the pins to activate the fans and work your way back. There are two ground control wires that come from the PCM to the relays for turn on. One is dark blu and the other is dark green. Both will show a ground when the PCM is calling for fans.