98 cobra cooling issues

hey guys i have been battling a cooling issue with my 98 cobra. i have put a new thermostat in it, all new hoses, radiator has been completely takin apart and cleaned out by a radiator shop. it has been tested for hydrocarbons. the car is not completely over heating but gets up to the "L" on normal sometimes a little higher. yesterday i had coolant flowing out of the radiator cap which was also replaced. i was sitting in traffic on the freeway in about 90 degree heat, but once the traffic started flowing and i got to about 50-60mph the car cooled right back down. it seems the car is overheating while the car is sitting, or moving slowly and its only happening when it is 85+ degrees out. the fan is turning on like it is supposed to. is there anything else i should check or anyone have a similar issue. i did have a SCT x calII on the car but returned it to stock for smog reasons. could this have messed computer up? i have had the programmer off the car for well over 6 months, but the problem didnt arise until the summer heat came. thanks any input will help.

checked water pump today, and that looks to be in good condition. maybe i will try another thermostat tomorrow...the third one. first one was defective maybe second one is too

well i finally figured it out. the connector to the fan was bad. if i wiggled the connector the fan would turn on which is probably why i overlooked it a few times (because the fan was on). the past 2 days the car has not been getting warm in the summer heat. heard they had a recall on these cars for fan issues, anyone else know about this. would like to get my money back for the fan which was like 400 bucks if i can.