Welcome to the list Gonzo!

I have a 72 280 SE 4.5 -- same horsepower, just bigger engine.

Ha, get used to a light foot. You can spin the tires on dry pavement rather easily with this beast. You may need to clean and lubricate the throttle linkage if it is sticky. A VERY light foot is a requirement. If you are used to "regular" lower horsepower cars, this guy is an eyeopener -- you will ram other cars in the rear all the time if you have a heavy foot!

However, a real lag then blastoff is usually a vac leak. Check the hose for the door locks, the injector seals (could also be the source of the gasoline smell), and all the many hoses up top on the engine. I've seen these with a large ball bearing in the idle control hose to shut off the "excess" air!

Gasoline smell can also come from bad hoses on the evaporative control canister by the rear passenger door, underneath. Mine smells of gas all the time, too, will have to investigate next dry day.

The vac leak will also make the tranny shift rather hard, and bang going into gear. The tube for the transmission is under the rear of the intake manifold, buried pretty deep. It has a banjo bolt (hollow bolt that goes through a banjo shaped fitting on the tube). Make sure there is a copper seal on the top, it seals against the aluminun manifold on the bottom. Check the connection to the transmission, too.

Sadly, another likely cause is the seals between the bottom and top of the manifold -- there are eight rubber rings in there. You can check by listening for leaks or by spraying some WD40 down there with the engine running -- changes in idle will indicate a leak.

Another possibility is a bad or out of adjustment throttle position switch. Big assembly on the side of the throttle housing. Could be not signalling throttle changes properly. Vacuum leak is the most likely though, since the tranny goes into gear hard.

Check the left exhaust manifold -- mine is split down the "y" in the center, makes the car rather loud. Also check the condition of both mufflers and the pipe connection in front of the front muffler, it often leaks.

Any good leather cleaner will take the crud off. You do need to get some Lexol or Leatherique leather treatment, too. Cleaning will remove the oils from the leather, and it will get brittle and tear. Don't wait, do this right away.

Good luck, ask questions, you will love this car!

Peter

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1972 220D ?? miles
1988 300E 200,012
1987 300D Turbo killed 9/25/07, 275,000 miles
1985 Volvo 740 GLE Turobodiesel 218,000
1972 280 SE 4.5 165, 000 - It runs!