bjjbadboy

Hey guys heres thebwhole story
05 350z 50k miles and babied
i dont remember having touched anything with the coolent system for starters.
this winter i noticed there was no heat when the car was at idle. Read up said i have air in the system and to flush and bleed. I left it till the weather was warm bc i dont use her much in the winter.

Recently left the car running while i was talking to a buddy, next thing you know overheating spitying fluid everywhere.

Again homework says air, tstat, fans.
but car works 100% fine when driving and ive been super busy so i put it off. Until now the other day im in heavy traffic and i see my temp start overheating. I blastef the heat and thankfully would start moving and the temp would go down, this happened 2x very scary drive over bridges lol.

So of course now im working on it.
Drained the radiator and filled with fresh fluid. Filled slow and saw fluid fill over the bleeder valve, closed it. Filled radiator until full. Ran until hot, reved to 3k no leaks, let cool, level still at the top of the radiator fill. Did this again but with the heat on, i dont hear any air but my car is loud... okay i think all good. Let it run long and sure enoigh temp stsrts over heating.

now since its fine when its moving doesnt this still suggest air? when i left it running and it started to overheat i looked at the fans. The drivers side was not turning on at all shouldnt it be on when the car is at operating temp? The passenger fan did turn on. Semmed slow at first but then fast.

What should my next step be? When i drained the radiator it poured out then dribbled then poured again suggesting air correct? Am i just not bleeding it correctly? Can i Wire the fan to the battery to insure its dead or if it works see theres a problem someplace else. Since the fan not on, tstat?

Thanks in adavanced

bjjbadboy

Hey guys update. I drained and refilled. Before bleeding the top radiator hose was hot but the bottom one was cold (i didnt hsve a spill free funnel so i jimmy riged a radiator cap and filled the over fill with clean fluid and hung it high this way air would psss through the rad cover up and out the over flow and fresh fluid would flow back in I also squeezed the top hose until i stopped seeing bubbles) prior to this i opened the bleeder n filled slow till fluid came out and closed the bleeder and continued to fill.

after this whole process the bottom was still cold and she started over heating at idle after a drive And the drivers side fan wasnt on so i gave it a tap and it started up. Bottom hose hot and temp dropped. An hour later ran the car at idle hitting 3k let run hot bottom hose hot drivers fan not on.

So would an air lock stop the fan? 2 seperate issues and i cleared the airlock but my fans are donzo and recalles? I didnt pull the tstat, if it was bad hitting the fan wouldnt kick it on and that bottom hose wouldnt be hot. Oh and my heat is hot again at idle..

Im thinking fans been shot and the little the car has been in traffic caused evaporation and the air pocket. i fixed the airpocket but the fans donzo. Get nissan to recall the fan. Replace the tstat oem since ill be there and rebleed. please give me some thoughts. I need my car for a big interview tomorrow but its driving through NY and Jerz could be hella traffic

dkmura

iTrader: (64)

There's likely two separate problems: the first involves the radiator and makes me wonder whether taking it to a radiator shop and having it fully checked is worthwhile. The second issue is likely a relay or motor issue with the fan. When was the last time you changed the radiator fluid?

350zchad

iTrader: (1)

Thermostat comes to mind

bjjbadboy

Thanks guys. Okay so ill pull the the tstat tomorrow and test it to rule that out.

How can I check the fans out and isolate the issue down to the relay? Figure gotta be a way just to give each fan 12Vs and see they kick on. When you flip the AC on your hear the relay but pop but need to tap the fan, other times it came right on? I checked them again and same thing even with the AC on, doesn't matter which fan but it needs a push then they both go

So if the fans have been going on and off wrong just driving has been enough to make the car not over heat? IT HAS NEVER OVER HEATED. THE FIRST TIME WAS SITTING IDLE NEXT IN HEAVY TRAFFIC.

Also the heat at idle is MUCH hotter but I still feel like it gets hotter when I rev it

bjjbadboy

To add. This is the first time draining and filling the radiator... I'm a bad dad...

Just got off the phone with Nissan and they won't cover anything. Never sent any info about these fans crapping out. Think it's BS they extend the warrenty to 84k I have 50k but bc it was 80months I'm out. If I knew this was an issue I would have looked into it 2 years ago. I would bet these haven't been working for a while I just haven't been in traffic and never really let the car sit idle when I think about it. For probably a few years

bjjbadboy

So I'm pretty sure I got all the air out Bc the heat is hot at idle. It's hotter when you hit the gas though. This is she still overheats after driving and letting it idle so I looked at the fans and the drivers side does not come on... Give it a little tap to start it and it starts and everything cools and works great. Also you can hear the relay click to turn it on it just won't unless you help it.

So is it safe to say the crappy fan is shot and to just oem replace it? If it was the tstat it wouldn't be firing up the relay correct?

350zchad

iTrader: (1)

if you tap it and it starts.. sounds like bad fan or connection (be careful with your fingers)

bjjbadboy

By tap I mean hit it with a screw driver lol. I need my digits lol. How would I test the connection. I'd love to pull the harness off and plug 12v and a ground directly to the fan but I don't want to short anythint

350zchad

iTrader: (1)

IDK, not my expertise, I mean how much is a new fan, just buy it

i8acobra

iTrader: (6)

You can buy just the fan motor. Do it.

Dank the Tank

I literally just had this issue with my 05. I replaced the radiator fans with a set of mishimoto fans (about $50 more then OEM) and my overheating problem went away. turns out the factory rad fans were a huge issue with the early Z's. good luck!

AGreenZ

I think I may be having a similar issue not sure whats going on though. My car has been fine ever since I had to replace the radiator and fan assembly but today in traffic the thermo gauge was going up so I turned the ac off and put the heat on to draw it from the engine bay and it went back to normal/ Checked it when I got to work and the one fan isnt turning on so idk.. Ill have to take it to nissan and see if they can figure out whats up.

bjjbadboy

I'm about to order just the motor for the one fan that isn't kicking on instead of trying to clean it since its like $40...
Can you when it starts getting hot and you manually (not with your hand) push the fan and it starts work? This is my case so it's pointing at a gunked up motor imo. Do you hear the relay click on? When you put the AC on you'll hear a click its the relay turning the passenger fan on. Examine that fan should be on. You'll hear the same click when the engine is hot and needs the driver fan to come on.

Not sure where you'd go from there but I think it would be to change the fan relay. Dudes on hear could probably help way more from this point. F Nissan never got any notice about these crap fans or I would have had it fixed before the problem and almost getting stuck on a bridge and tunnel in traffic