I have an 89 IROC-Z 350 TPI. . . Recently I had the works done to my car with maintenance. . . New radiator, fans, radiator cap, coolant hose, belts, thermostat, transmission cooler, all new fluids, Hawks Performance Ram Air Scoops, K&N Filters, water pump, heads rebuilt with port and polish, head gasket, MSD Cap, MSD Rotor, MSD Ignition Wires, Bosch Spark Plugs, Hooker Headers, Flowmaster Exhaust, and new timing chain. . . After all that the car was running great for several days than out of no where the car shut off on me exiting the freeway. . . Coincidently I was on the way to my mechanic's shop which was right off the highway. . . I waited a little bit and the car started up again. . . My mechanic checked it out and everything was fine. . . On my way back I gunned it a little on the freeway up to 90 mph and I started to slow down my temperature went up. . . As the temperature rose the engine than shut off. . . Same thing as earlier I waited for the car to cool down a bit and the car fired right up again. . . After doing some reading on this forum I double checked for the lower air dam and I do have one. . . The fans are working and the coolant is flowing. . . This so far is really bugging me since I spent so much money into getting the car perfect and it starts acting up again. . . I have never had this issue when I first purchased it even though one out of the two fans were working. . . Any thoughts on what is happening would be greatly appreciated. . . Thank you!

 

I have to ask, what thermostat are you running?

No leak/burning coolant?

Is the air dam blocked?

How many passes does ur new rad have?

Have you checked you CTS?

 

No leaking or burnt coolant

No the air dam has perfect clearance

I don't know how many passes it has it's an OEM replacement from O'Reilly

The CTS is brand new cause my boy replaced it thinking it was that causing the OEM temperature gauge to not work

 

Thanks for the attempt Black88Z but I figured it out it was the new fans not being strong enough. The weird thing is that it still stalls out of no where and this happen to me at a stop light.