I had similar issue and and it was the tiniest leak (never dripping) around the end of a small rubber hose that goes into a metal pipe with just a basic hose clamp. Some coolant was drying out there and caking (crystals) and that was enough to make that smell.

Yes you do have a leak. Put your Z up on jack stands and take off the belly pan. Get a flashlight and look around for dried up green or blue coolant. Use a cooling system pressure tester if you got one. This will help force coolant out of any leak points so you can see coolant dripping. I know a common leak point on our cars is the plastic restrictor between the two right side heater hoses. Mine started to crack. Or, check the weep hole for the water pump. You'll see witness marks on the left hand side of the block.

Get a UV dye kit. Put the liquid in the coolant, Run your car for a day and then use the UV light and the leak will show. Super helpful.


Sent from my iPhone using Tapatalk

Petrosin Pentofrost A3 IS the coolant Nissan rebrands in their containers. Best price at Rockauto when ordering other parts. Also available at Advance auto.

First leak point to check is the plastic mender in the middle of heater hose next to the battery box. My upper radiator hose was getting dried coolant at the connection to the radiator so I changed both radiator hoses, both heater hoses (used a metal mender) and employed a 170* thermostat. There's a bunch of smaller hoses that run along the top of the engine to the throttle bodies etc. so give those a look as well. The FSM provides a schematic for all cooling hoses for reference in searching down leaks. If that all passes the inspection check the radiator core then unfortunately, it's onto looking into a head gasket or heater core leak.

Additionally, if you have silicone hoses, Z owners have reported coolant smell due to weeping through the hose itself, yes even when new and why I stuck with the EPDM material hoses Nissan used.

I lost all that was in the reservoir in about a week. The leak has to be somewhere that is pointed at a hot engine part and it is being evaporated as there is no residual on the floor and I can smell burnt coolant. I will be doing a pressure test this week. Any suggested hoses or other weak points base on that info would be appreciated. Thanks

And sorry, I missed Tracionless's post before I sent my last, will check those locations, thanks

So I put some dye in the coolant and can't find the leak. I suspect the waterpump is going bad. Can anyone tell me if there is a weep hole for the pump? I know it's behind the timing chain cover but wondering if I can find some evidence of leak around the weep hole if there is one. Thanks

Antifreeze Loss/NO Leaks?
 

Not sure if there is a weep hole that drips external to the timing cover, but the water pump is above the crank pulley slightly to the driver side of the car. I’d look around there more and also along the driver side of the engine block (to find out if there is a leak/if there is a weep hole)

You’re sure there’s no coolant in your oil? How long did you run the car after putting in dye?


Sent from my iPhone using Tapatalk

I have driven the car at least 100 miles since putting in the dye. I am pretty sure there is no dye in the engine oil as I waited till absolute dark, pulled the dipstick and checked it with a blacklight, no fluorescing. I suspect the waterpump for two reasons: 1. Losing coolant with finding a leak, and there us a bearing noise as well. I would think that if the coolant is leaking through a bad bearing, it would eventually show up in the oil as the cam chain is lubricated right?

Hey Dreadnaught,
Were is the weep hole? Thanks!

It is on the backside of the timing cover.

If the bearing on the water is going bad you would hear a grinding noise and there would be oil in the coolant. You would also have axial and radial play if you moved the water pump by hand. But, you can't do that since the water pump is driven by the timing chain.

The weep hole is on the left side of the timing covers. Check around and A/C compressor. That's where you should see coolant if the water pump is leaking.

If the right side restrictor that goes between the two right side heater hoses you will have coolant/staining on the right side of the bell housing. You can see the heater hoses from the top back right of the engine.

Have you confirmed that's a restrictor? Mine was plastic and free flow with OE Nissan hoses when I replaced it about 2 mos. ago with metal. :confused:

Looks like a restrictor to me. It is a common leak point on our cars cooling system.