After sitting disassembled for 16 months, I reassembled my engine. I had the head reworked with all new valve guides. All new seals in the head and block. New timing chain and guides.
Well the car burned gas like crazy. I replaced the plunger seal in the fuel distributor. No improvement. Next came fuel pressure regulator. Then all new injectors. Still 10-12 miles a gallon. After 4 tries at rebuilding the fuel distributor I learned that rebuilding one of these is best left to experts.
I bought a used fuel distributor from a local tech that knew the engine it came from. In other words he knew it was good.
Still no improvement. So, look to the exhaust. I figure I have nothing to lose by punching out the catalytic convertor to see if there was a restriction. If there was a restriction then it would be apparent. If there wasn't then it's just another needlessly replaced part.
Well, all indications point to a gagged cat. I have driven the car about 500 miles and the gas mileage is back up to 22 mpg combination city/highway. No black soot on the garage floor. Smooth running on the open road at 200 less RPM @ 60mph than it used to run. Oil consumption used to be 1 quart/400 miles. Too early to tell exactly what it will be but the dipstick level hasn't budged in 500 miles.
The temperature here in the swamp dropped to 45 F this morning. Opened the sunroof and set the climate thumbwheel to 22 C. The 17 mile open road trip to work was one of the most pleasurable I have ever had. This old Benz drives pretty dang good !!

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