I can't find any literature on this and largely agree with what everyone else has said, but Wikipedia is pointing me toward two things of interest (with book sources to back it up-- I have access to one but need to go to my college library to get it). For one, coyotes
can be picky with what they eat, at least according to H.T. Gier in his article in
The Wild Canids: Their systematics, behavioral ecology, and evolution (1974); animals you might expect coyotes to prey on, like brown rats and shrews and moles, aren't incorporated into their diet. On the other hand, foxes, whose diets overlap more closely with coyotes compared to wolves,
readily eat those. So it's possible that coyotes do exercise some pickiness
when hunting. But are they picky when it comes to carrion?
I'm going to divert a little to the topic of cannibalism, first. I know that cannibalism at least occurs in wolves:
Wolves are known to engage in cannibalism during times of food stress; injured members of the pack are especially vulnerable.
page 362,
Land Mammals of Oregon, B. J. Verts and Leslie N. Carraway
R.A. Rausch (1967a: 258) wrote the following about cannibalism in wolves: "Once a wolf is injured or handicapped, fellow pack members may consume him. I have recorded six occasions where a wolf caught in a snare or trap was devoured, except for the skull and a few bits of hair and viscera, by remnants of the pack. Aerial hunters who leave unskinned wolf carcasses in the field have returned the following day and found the carcasses being deouvred by the remaining members of the pack.
Wolf, L. David Mech
I don't think it would be far off to assume that cannibalism is also possible for coyotes-- which brings me to the second point of interest on the Wikipedia page. In
The Clever Coyote, apparently coyote fat has been successfully used as bait to lure coyotes and carcasses are "readily" eaten. (That's the book I have access to but don't have in my hands right now.)
I brought up cannibalism because I don't think the "idea" for a coyote of eating itself (a canine) would deter it from eating another fellow canine if it's already eating other coyotes.
Cannibalism aside, coyotes are known to kill (albeit rarely) red foxes, and will kill
and eat them if they are in traps. I've seen arguments that coyotes do not kill wolf pups and small dogs to eat them and instead kill them for competition purposes; this seems to be true for foxes, too, but some eating of the fox carcass by coyotes does take place.
Seventeen accounts described trapped (leg-hold) or snared foxes killed by coyotes. Many of these foxes were described as mauled, ripped apart, or fed upon. ... The relatively common occurence of coyotes killing foxes in traps likely results from inability of trapped foxes to flee or adequately defend themselves. [This sounds opportunistic, however m]any trapped foxes reported killed by coyotes possibly were dispersing juveniles caught inside coyote territories.
page 631-32, “Observed Interactions between Coyotes and Red Foxes,”
Journal of Mammalogy, Alan Sargeant and Stephen H. Allen.
I don't think there's any "intimidation" or any squeamishness involved because of any similarity as a canine. I do, however, agree with everyone else on the point that it is likely rare for a coyote to consume meat from a wolf carcass and vice versa.
(You all gave fair answers, but I'd encourage you to use sources in the future.)