sorry to say, but that is sad... you ripped a co-worker off when you could have helped him fix a simple problem... it is sad the people that get riped off... I don't care your justice saying he should have taken it to a mechanic ect ect... hell I don't even know cars that well and washed engine, then car acted up, help the guy out, don't steal his DD... my 2 cents
if someone posts an ad online for a car for sale with mechanic problems, in my eyes that is fine, as they are fed up with it and want it gone, don't care to fix it, but it seems like you saw him in need, you realized the problem, then kicked in his knees and basically ripped him off... if he was selling it and has another car ect ect that is fine, but to take advantage of someone who is not as smart as you, I find that very dishonest, especially to a co-worker