rb25 overheating

[rhd240]

ok i have searched the forum and im still stuck..i have a s1 rb25 s13. has been overheating so i took it to my mechanic who is a nissan mechanic . we came to the conclusion it was a headgasket. replaced gasket, water pump, nismo thermostat, cx radiator, and the timing belt and tensioners . got car done and went to drive it home today and overheated again .the cooling system is new and fans are workin but not dropin the temp unless its just idlein. it has me and my mechanic stumped. can anyone help? tired of drivin my bosses raggedy mustang....miss my nissan

[Cjmartz2k]

Stock ECU? Overheating going down the road or just idling? 100% sure on the timing? Mustang a V8? What year?

[rhd240]

stock ecu, idle bounces from 206-209, runs hot while driving, 100% on timing, mustang is an 89 4cyl. auto im borrowing from my boss....p.o.s.

[Gabes13]

You should get a cute little coolant breather tank. it'll help eliminate deadly air bumbles in your precious cooling system.

[amakadius]

zounds like you have air pockets in your system that have to be bled out.