1992 500SL 108K: Intermintent yet daily hesitation

[lymlyt]

1992 500SL 108K: Intermintent yest daily hesitation.

Cold start: Strats right up but with some idle "stumbling" but smoothes out in a few sec.
Warmed up: Occasional, but daily hesitation. Feels like fuel dilvery issue but
unsure. When it occurs, oil pressure gauge is fluctuating under 1 bar.

Any ideas?

thanks!!

[lymlyt]

Update, 1992 500 sl , 110K. Problem: Intermitent miss fire
after warm up.

Scenario:
-Drive in warm weather for about 30 mins.
Engine has to be hot, 100+ degrees.
-Turn off car after about 30 mins.
-Let cool down for about 20 mins.
-Restart car, occassional miss fire, hesitation.
-No problem after car has "cooled" down and starts cold.

Observations:
Oil pressure guage indicates spike below one bar when hot at idle
but miss fire doesn't always follow.


Mechanic, after several days was able to reproduce problem, believes:

-its ignition oriented. either spark plugs or wires.

any ideas thoughts?

thanks!

[moakesr]

I would check the distributor caps and rotor arms.

The seal behind the distributor cap goes hard with age and allows moisture in, then carbon tracking and misfires start to happen.

If you remove the caps and see black lines between the center and the outer contacts then the caps (expensive) and probably the seals (cheap) will need replacing.

Good Luck