Ive always used citrus cleaner, it really gets the caked on grime off. I take the car to the self serve car wash spray the cleaner on the engine, while I get my change for the wash the cleaner does its work. The good thing about the citrus is it doesnt leave any white spots on the hoses and black plastic.

 

Please get some CDR engine cleaner. The only place I know where to get it is on Amazon. Follow the instructions in this link, it will really help. http://www.ocdetails.com/. Look for Engine Cleaning. You will be very impressed with the results. Take it from a detailer.

 

i agree, engine degreaser's would be a much better route to go. They are designed for the engine specifically, so they can focus on the grimes typically found within the engine.

 

not that i want to revive a dead post but here is what i do;
I take my car to the coin op car wash and select tire and rim cleaner. hose it down for a bit. let it set for a few min while i spray the rest of the car and then use the rinse and powerwash the engine clean.

 

Be VERY VERY careful with this method ... When I drove a Tow truck I towed 3/4 people a week out of the car washes that soaked the electrics

 

I never hand an Issue and i have done many diffrent cars; I used to work at a detail shop and thats how we cleaned the engine bay.