The engine oil looks jet black about 1 minute after leaving an oil change. A little soot and carbon in the old engine oil turns the new oil black soon after it mixes. Greasy I don't know about.
Limp mode won't be fixed with an engine oil and filter change, 100%. For all you know, your test drive could have popped something loose and cause limp mode to start to appear. I wouldn't get too angry since limp mode is a very common problem and it pops up suddenly.
Air bubbles in the fuel line coming out of the fuel filter can be a bad o-ring or other. A few bubbles is normal, many bubbles is abnormal. I can't tell you how much is too much unless I were to see it running.
Sent you a PM with some mechanics and contact info.
Limp mode won't be fixed with an engine oil and filter change, 100%. For all you know, your test drive could have popped something loose and cause limp mode to start to appear. I wouldn't get too angry since limp mode is a very common problem and it pops up suddenly.
Air bubbles in the fuel line coming out of the fuel filter can be a bad o-ring or other. A few bubbles is normal, many bubbles is abnormal. I can't tell you how much is too much unless I were to see it running.
Sent you a PM with some mechanics and contact info.