it's very dangerous trying to tow with a 4 cyl, it doesn't provide enough power to go up hill, pulling up on the freeway ram, trying to merge at freeway speed. u could ofcourse, but u risk over forcing ur engine + putting urself in dangerous driving situation .
I wouldn't recommend towing with a 4-cylinder Accord either, but I don't think there would be an issue if he's not driving in those conditions (up a hill or on the freeway) and follows the recommendation in the owner's manual...
"Your Honda has been designed primarily to carry passengers and their luggage. You can use it to tow a trailer if you carefully observe the load limits, use the proper equipment, and follow the guidelines in this section.
The total weight of the hitch and trailer (with brakes) plus its luggage must not exceed the maximum towing weight.
Max. towing weight
Trailer without brake = 1,102 lbs
Trailer with brake = 3,307 lbs
The 'towbar downward load' should never exceed 50 kg (110 lbs) on 4-cylinder models/70 kg (155 lbs) on 6-cylinder models. This is the amount of weight the trailer puts on the hitch when it is fully-loaded. For a trailer weights of less than 500 kg (1,102 lbs) on 4-cylinder models/700 kg (1,550 lbs) on 6-cylinder models, as a rule of thumb, the towbar downward load should be 10 percent of the total trailer package.
For example, if the trailer and its load weigh 225 kg (500 lbs), the towbar downward load should be 22.5 kg (50 lbs). Adjust trailerís luggage to change the towbar downward load. Start by putting approximately 60 percent of the luggage toward the front and 40 percent toward the rear. With a trailer package of more than 500 kg (1,102 lbs) on 4-cylinder models/700 kg (1,550 lbs) on 6-cylinder models, you may need to adjust the luggage weight toward the rear. Never load the trailer so the back is heavier than the front. This takes weight off your carís rear axle and reduces traction."