M117.986 WEIRD symptom

[PanzerSD]

This is a weird one.

Generally, my engine runs well, but has a miss throughout the RPM range, struggles up large hills in 3rd and needs to have cams replaced.

When I'm driving around for a period of time, and the engine reaches a nice steady 80*c, if I park it somewhere and let it idle in Park for a few minutes, takes as little as 5, when I go to leave after sitting, the miss is gone, have PHENOMENAL power, and runs and drives like a car that is a half ton lighter...

However, after about 10 minutes of driving, it all returns to normal...
What gives??

My first suspect is the fuel filter/pump. That is, the sit time is allowing pressure to increase in the system to afford the extra enrichment...

[Tomguy]

Maybe the fuel tank strainer - where the idle vibrations allow the particulates to fall off the strainer but once you get going, they're right back on it in short order. Just a theory but the car is fairly old - has the strainer ever been cleaned?

[PanzerSD]

Fuel tank strainer....That should be right there at the bottom fitting of the tank? When I replaced my fuel ->pump feed hose, I didn't feel anything up there in the tank...
could the accumulator be shot? What goes wrong with those?

[PanzerSD]

I see now, I just looked up a photo of one..it IS the fitting...also, it's long, too long for a finger to detect. and looking at it's shape and length, It also explains why the car runs better on a half tank of more...because the sides are plugged more than the top, thus, when the fuel level reaches below the top of the strainer, the fuel getting thru reduces, resulting in a power loss....definitely gonna check that one out this weekend...