Join Date: Nov 2008
Location: Toronto, Ontario
Sounds kind of familiar.
On very cold days (at least for here in S. Ont.), say about -15 C or colder, my Ranger would make what could be considered a "whining" sound upon starting - I would say that it's actually more of a "howling" sound - kind of like a high speed turbine going.
At any rate, after some research, the best answer I could come up with is that it is related to the IAC (intake air control) valve, and that it's not that unusual (at least on the Ranger, and maybe other Ford products as well).
Apparently it can also occur with modifications to the air intake box when an increased volume of air is allowed to flow through - though I doubt as loud as what is encountered when the air is extremely cold.
I found on another Ranger site a warning that modifications to the stock air intake box (to allow increased air flow) could result in increased engine noise upon start-up. My best guess is that this could all be related to an increase in air volume flowing through on starting up (i.e. colder air = increased volume), and its effects on the workings of the IAC valve, with the net result: the whining/howling sound.
The first time I heard the sound it scared the **** out of me because I thought the engine was racing out of control and I immediately shut off the engine. Restart, with the same sound (I noticed the rpms were a bit higher than usual, but didn't increase past about 1200), and the sound went away, like yours, about 10 seconds later (rpms dropped back to normal idle speed too).
Now I just take the noise in stride - I expect it when its cold - and after extreme cold start-ups, the sound goes away when the rpms drop. Since I imagine that other Ford vehicles would utilize the same or similar configuration/parts in their systems, this may be common across the board for Ford products.
Every winter, when extremely cold, I've come to expect this phenomenon. My truck now has almost 300,000 km on it, so I don't think it has affected durability.
Hope this helps.
'03 Ranger Supercab, 4x4, 4.0 liter SOHC V6, auto, FX4 Off Road Package (Level I)