1990 300sl mechanic says fuel distributor bad

[whosurpopi]

The car seems like it misses some times and some times it seems fine, Mechanic tested fuel distributor, and says pressure is fine, but when he tested fuel (mass i think) the bottom of the distributor is good, but when he goes to test the top, the car shuts down. Does this sound right to replace whole distributor, or is there another explanation. Thank you.

[1991300SEL]

I would get a 2nd opinion. This item cost tons of $$$ and many mechanics mis-diagnose it.

[whosurpopi]

I see there is an o ring gasket for the fuel distributor, if that was to go bad, does anybody know if it would reduce the upper mass reading?

[sbourg]

I would get a case of Techron, and run a tankful of gas with a couple bottles of the stuff added. See if this helps. If better, keep adding a bottle of techron/tank until problem disappears. If this doesn't help, get a second opinion before replacing the fuel distributor.

Steve

[whosurpopi]

I will, I have been looking on internet and have found rebuilt one for $300 but something just doesnt sound right.

[bwheitman]

Have you checked your ignition distributor? Those are known to cause idle issues, and much cheaper to replace than a fuel distributor. If it has not been replaced do it, see if that helps, if not it should be replaced anyway. Also the plugs and wires. I had a rough idle on a 103, it was plugs, wires, and distributor, car only had 42k on it, but now it runs wonderfully.
Brian