2018 v6 Nissan laughing Hyena when cold

[Rochev]

2018 Pathfinder.
I first noticed this a couple of winters ago probably around 50k and I'm at almost 110k now.

When it's below about 25f on an overnight cold-start there's what sounds almost exactly like a "laughing Hyena" coming from the engine bay and I'm worried it's the water/oil pump. It will do it for about 10 seconds and stop. 7/10 times I'd say it happens. Hoping someone on here knows what I mean and has figured it out or knows what it might be. It does not sound normal or good!

 

[Bailes1992]

But Hyenas don't laugh, do they?

 

[Number_35]

2018 Pathfinder.
I first noticed this a couple of winters ago probably around 50k and I'm at almost 110k now.

When it's below about 25f on an overnight cold-start there's what sounds almost exactly like a "laughing Hyena" coming from the engine bay and I'm worried it's the water/oil pump. It will do it for about 10 seconds and stop. 7/10 times I'd say it happens. Hoping someone on here knows what I mean and has figured it out or knows what it might be. It does not sound normal or good!

I would start by using a stethoscope to try to locate the source of the noise.

If that isn't conclusive, I would remove the serpentine belt, and try a brief start without it in place. (Brief, because you don't want to run the engine long without turning the water pump.)

If the noise is no longer present, you'll know it's one of the belt-driven accessories.

 

[WeyounDS9]

slipping belt.
As the belt warms up it gets less slippery and stops slipping.

solutions: tighten belt, belt dressing, or (best) replace as neccessary.

 

[Boomer]

Try applyinf a few dabs of SILICONE grease to the ribbed side o the belt in various places. This can work wonders at calming wierd belt noises. I have posted this o BITOG numerous times with positive feedback.

 

[Rand]

slipping belt.
As the belt warms up it gets less slippery and stops slipping.

solutions: tighten belt, belt dressing, or (best) replace as neccessary.

Belt dressing is only for Vbelts

Try applyinf a few dabs of SILICONE grease to the ribbed side o the belt in various places. This can work wonders at calming wierd belt noises. I have posted this o BITOG numerous times with positive feedback.

I wouldnt increase the slipping to fix a noise. Would you apply grease to brake pads to fix a brake noise?
I'd start with a new belt and also checking the belt tension.

 

[Rochev]

I'll check the tension tonight. It doesn't sound like a belt though but fingers crossed. Bailes1992, if you look up "laughing Hyena" that is what it sounds like

 

[thastinger]

If you are able to turn off the AC compressor it might be a good idea to start it cold with that off and see if it still does it.

 

[Boomer]

Small amounts of silicone grease do not cause slippage. It just help stop what I think is micro friction areas that cause noise when the small areas of rubber belt cling and release from the pulley.

 

[JTK]

I follow the R52 chassis pathfinders quite a bit having owned my 2019 for going on 5yrs and 100k miles.

You don't hear of serpentine belt, or rotating element noise with the VQ35DD often. A common chirp, clacking or rumbling noise maker is the electric cooling fans. The bushings go bad on the fan motors.

You'll have to try peeking under the hood while someone cold starts it for you.

The only way to prevent the cooling fans and a/c compressor from cycling/running on the R52 is to have the HVAC system selected to "off". Otherwise, the fans and a/c compressor will disturbingly cycle on the coldest of cold starts with any and all HVAC settings selected. I assume it's the way nissan keeps the air "dry".

 

[Racecarfan2]

Could be the throttle body, In cold weather they can Ice up or if they have carbon build up it could be causing a whistling noise.

 

[Jdeere562]

Try applyinf a few dabs of SILICONE grease to the ribbed side o the belt in various places. This can work wonders at calming wierd belt noises. I have posted this o BITOG numerous times with positive feedback.

I would NEVER suggest grease on a belt!

I worked for a company that made ticket vending machines. They relied on belts to grip a ticket, then slide under a gate set at .025 so one ticket was vended, not two. They worked very well.

Some genius was having problems with tickets not coming out. (curled tickets) So he put baby powder on the tickets and belts, hoping they would slide under the clearance gate! Wrong idea! That just made the belts slick and slip on the tickets.
Tech we had to send out there was not happy, having to clean up all that mess to make it work right.

 

[Barkleymut]

also could be an alternator

 

[wavinwayne]

Accessory belt tensioner? Cooling fan bearings going bad? Timing chain guides maybe?

 

[SC Maintenance]

Does the Nissan Auto Active test still work on a 2018? It cycles through everything electronic turning it on and off - including the electric fans, for diagnosis.

VQ engines drive the water pump with the timing chains internally - your likely not going to hear that. Or the oil pump.

Its could be the clutch fan, their known to make a lot of noise on startup but not a screeching - more like a jet engine.

Might be the AC compressor kicking in for a dehumidification loop? I think you can pull a fuse or relay to disable it.

Could also be the belt tensioner - they get squeaky when cold.

Anyway, here is the auto active test:

Auto Active Test

1) pull windshield wipers up (so they don't scrape on a dry windshield)
2) open drivers door
3) ignition key and put in on position
4) within 20 seconds click the drivers door switch 10 times
5) turn key to off position
6) turn on and you should hear the horn honk.

Then it will cycle through everything controlled by the IPDM.