Car runs fine untill temp hits 40 then rough idle. Clears up when given gas.Tried today ran fine around block twice than started the same thing.Check engine light not on and am geting no codes.Spark plugs And wireing harness all good.Forget to mention when idleing rough if i put it in gear and give it gas it stumbles and coughs.But give it gas with no load and runs smouth after 1000 rpm. Could someone put me in right direction please.First time on board. THANKS

check the OVP relay, a big silver block behind the battery

__________________
1995 E320 119,000 miles

Checked ovd.I am sure is fine could it be mass air flow. do not know how to check mas air flow. Any other ideas would be great. THANKS WRENCH.

How did you check the OVP.. The part is notorious for your complaint and to check it you want to see if it has the NEW upgraded part #..
Archieves. 'OVP"

Arthur checked ovp only by looking at fuse.I am going to get part number off ovp after work.could i check with omm meter.going to archieves now. THANKS FOR REPLY.

New part# 000 540 67 45
Old 000 540 52 45