ok so i started noticing my engine overheating only at idle after last winter when i got some snow stuck up near my radiator. It only overheats at idle when im at a long stop or in traffic right when i start moving at a cruising speed it cools back down. i replaced my thermostat and had a shop bleed the system just to make sure it wasn't any air bubbles, but then still the same problem so just recently i replaced the fan assembly, and no luck still overheating i cant figure this out iv'e never really messed with cooling systems before, any thoughts?

 

Have you checked to see if the fans are coming on? This sounds like a fan issue. Could be a bad coolant temp sensor not allowing the fans to come on when the cooling system gets to operating temp. or could be damaged wiring to the fans. I would confirm that the fans are working before going any further.

 

Just replaced the fans so its not the fans themselves but no they havent ever turned on since ive had this problem

 

So that is the problem, fans not kicking in - temp sensor next - wiring check also

 

Ok cant seem to find a decent picture of where the temp senaor is, from what im getting the one that connects to my ecu is the one i need to change. All the pictures ove seen are wither useless diagrams or nothing at all

 

Workshop manual (use google - plenty of sites to download it from)
File CO.PDF
Page CO-31
Item 4 in the diagram

 

Just replaced the sensor today no luck

 

Ok I know you said you just replaced the fans. But are they coming on?

If not chase it down. If they are ignore the fan assembly and system entirely and move on.

cause your just wasting money and time just randomly replacing and chasing things down with out going from a-z of what where and why.

 

Ckd fan fuse/relay continuity?

 

They are not coming on

 

No i havent im not good with electrical ****

 

Just checked the rad fan fuse it was blown replaced it, just checking to see if it works yet

 

Had this issue with my G35, in the fuse block by the battery there is a Green 40amp fuse, mine was blown, replaced it and fan started working again.

 

Thats exactly what i replaced just wished i would of checked sooner feel like an idiot

 

Glad you got it sorted!

 

Yay guys! We got it!

 

Lol been there, did the whole check the coolant replace the relay, teardown clean and reassemble fan motors, then went oh wait what about the fuse ...

 

Wish my overheating problem was this easy of a fix! car has been running hot for a week now and noticed today that i have a blown head gasket!

 

What caused the fuse to blow?

 

Not OP but based on the info, snow jammed the fans, stuck electric motors caused overcurrent and blew the fuse.