My '87 SDL has developed a severe lack of power... to the point where the car is floored in drive with a cold engine, it won't move foward. The car is somewhat driveable after warming up for 5 to 10 minutes, but takes a long time to get from idle to 3000 RPM and it is not possible to start up hill. Power is at bit better past 3000 RPM and will go 70mph on a level highway, but it takes a long time to get to that 3000 RPM. (When cold, with the car in drive and floored, engine will not move past 900 RPM).

I've changed the both the inline and canister filters; lift pump delivers 9oz in 30 sec when measured via the return line. (spec is 5 oz). Car starts (both warm and cold) and idles w/o problem. I also bypassed the fuel T-stat with no change. Car has 93k miles. Also, this is likely the 1st time the car has ever seen temps below 30 F; not sure this is relevant. Problem came on over the course of a week driving 20 miles per day.

What should I look at next? I'm thinking fuel return valve at the injection pump. Other ideas? Thanks.

__________________
as ever
Paul

1989 560SL
1987 300SDL
1987 300TD
1983 BMW 633CSi
1972 280SE 4.5