My car is an 1998 Ford Escort with a 2 liters DOHC Zetec engine. Last year I noticed on the passenger side of the engine an oil leak that caused lots crud and oily dirt to accumulate on this side of the engine. The oil seemed to get in the belts and a short 20 min highway drive would send a trace of oil drops on the hood, engine side, etc. If I did not clean the underhood and engine bay once in a while, the right side would be really oily and dirty. when I checked for the source of the leak, I noticed the main engine pully was surrounded with crud, so I guessed it was a seal leak, probably the crank seal. The engine had about 70 000 miles at that point.

I added a bottle of auto-rx/castrol GTX and a new filter. Ran 2500 miles per instructions. At this point I did not bother cleaning the engine at all. For the first 2500 miles, did not notice anything special...maybe a little bit better mpg but not much, might be because its getting warmer here. Then I changed the oil and filter again and used penzoil yellow bottle (I use whats on sale). Then after 1000 miles, nearly halfway in the rinse phase, I decided to do a complete cleanup of the engine bay to see if the leak was improving. Indeed!!! Right after cleaning I did 300 miles and I was in shocked when I poped the hood afterward....not a trace of oil on the hood! the engine is still very clean , obviously the leak is pretty much gone... I notice the engine is running a little bit smoother too...really I did not expected much but it seem that this product really works! Can't wait until my rinse phase is over, I know my engine will be clean and leak free!
thanks for the good product!  

Phil