it has worked on my 1995, 1996 om606s too. Never had air issues on those cars. The 1999 was air free too. Only replaced lines as because I was there for delivery valve seals and glow plugs. But i have a decent amout of air coming out of the bottom of the pree screen housing. nothing coming out of fuel thermostat to top of screen. Tried new orings, new filters, new filter housing. Even put the old line from fuel t stat to pre filter back on to try that. Still air. Not much at idle, but raise rpm and its pretty bad.