hello,definatley replace the ovp,its located behind the black plastic shield,located behind your battery,the cold start injector could be an issue,but most likley you may want to check the eha,its located on the back of the throttle body its a black square sensor with a 2 prong plug facing passengers fender,these go bad and cause cold start issues,its $250.00 new $40.$60.00 on ebay,if its defective you will want to replace it and have the air fuel ratio adjusted.,most common diag for a defective eha is a strong smell of fuel when starting,and hard cold starting,with ruff almost stalling idle,after 20-30 second the idle will level out.good luck.

Thanks for the reply! I definatley want to change the OVP but it won't be until after this trip due to it being 200$+ the symptoms of the bad eha sound very similar to mine, I do get the gas smell when it starts really ruff but I always thought it had something to do with my tank vent valve which is missing lol the idle can be seriously rough and it won't run on all cylinders for around 5-6 seconds but then they come back on and it runs smooth.

Another thing is, this car had amazing idle, when we got it with 127,000 I always double checked to make sure it was still running cause you couldn't feel the engine, but then on occasion it gets these little very noticeable dips in Rpms... Don't know if that has anything to do with that.

The only reason this really bugs me is when it sounds like it's not going to start at all, it scares me cause I'm not sure if it will, but I just have to give it gas and after a try or two more she kicks on. And to make it even more weird, sometimes it starts just fine! LOL

I will definitely look into all those mentioned in the above posts, although I'm not sure if I can afford to replace them until after this trip to Texas.

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86 Peugeot 505
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The OVP has a fuse or two in top - depending what revision you have.
They are not $ 200.00
You can get a second hand one cheap from that great auction site to test out. If this is the problem you can get one here - forum sponsor for $80.00

see this : http://catalog.peachparts.com/ShopByVehicle.epc?q=1991-Mercedes--Benz-300e--Base-Body--Electrical&yearid=1991%40%401991&makeid=63%40%40MERCEDES+BENZ%40%40X&modelid=6195%3AMBC|1507%3AED|10000013%3ASM|20%3AEB|613%40%40300E+Base&catid=241959%40%40Body+Electrical&subcatid=242003@@Overload+Relay&mode=PA