I have a 1984 380SL that I purchased from a mechanic. It sat for 6 years, so I did the expected maintenance, which was dropping the fuel tank and cleaning it out, replacement of the fuel pump and filter, fuel pump relay, idle speed control module and valve, overload relay and all of the temperature sensors. I have not been able to relieve the problem that I keep having.

After driving for 20 minutes or so, the vacuum drops off (dash gauge goes to the opposite end of scale from the "economy" reading) and the engine starts bucking and exhibiting a starved fuel condition, just like when one runs out of gas. If I stop for a while, I can start up and drive another 10 minutes before it returns. I did not replace the fuel reservior nor the damper and am wondering whether this could be the source of my problem. I took it to a dealer and he had it for three weeks, told me to replace the items listed here and then sent the car home. Anyone experience a similar problem?

 

and what are those lists?

there are vacuum gauge that you can buy where it can tell you wether it can be the timing, ignition or intake leak.

your engine needs special checking procedure in order to locate the problem.