Cold start easy, Warm start hard on my E320
 

Now that my Florida E320 is experiencing cold Wisconsin weather it is starting to have some problems. first problem is it starts easy when cold but warm starts are almost embarrassing. :( I don't think its the fuel pump or filter but that is where I was going to start. any suggestions?? Also, where is the fuse for the air pump. this was originally a CA model and I suspect that the air pump is making that horrible noise in the morning. your comments will be greatly appreciated!
Thanks in Advance.
Adam

You must be more specific. WHat do you mean... does the engine turn, but not catch, when warm? Or what?
First thought is the OVP......

yes, the engine dose not catch. i usually have to floor the gas and repeat the ignition process 3 or 4 times before it starts.

I figure if it's a fuel delivery problem, it would occur whether the engine is warm or cold...I too believe that the OVP may be what's causing the problem...

I had the same problem on my 300se and changed lots of parts,
and did tune up distributor cap,wires ,sparkplugs and no difference after 3 months I tried techron fuel injection cleaner and
the car would start when hot first try (I felt like im in heaven).
As soon as I refield the tank the problem came back then I thought as long there was fuel injection cleaner for like two weeks the car started hot first try with no problem. Then I decided to take it to a mercedes shop and told them my story what's going on they said the solution to my problem is to force some kind of special cleaning solution through the injectors from top of the rail where the injectors get fuel not thru the gas tank. I paid $119.00 in Ohio and that completely eliminated the hot start problem and its going on three months since the dealer cleaned them.
Before you spend your hard earned money try a bottle of good fuel injection cleaner (always good idea to change oil after)
if the problem goes away (cheap way) then take it to a shop so that they can clean em thru the fuel injection rails(MoreExpensive). Good luck

well.... I checked the OVP relay, the fuse and checked it with multimeter and a 12v sorce. works fine. I use Jectron fuel injector cleaner every 3 months. Any other suggestions??
Thanks!
Adam

follow-up
 

did you ever fix your problem with difficult warm starting?
i'm having the same problem.
-shawn

Me, too! I've changed the filter, accumulator, on and on... Sometimes it won't start at all when hot.

Same problem on my '96 c280 resolved with new fuel regulator. Diagnosed by pulling the vacuum line to the regulator and finding drops of fuel. It should be dry. Easy DIY.

same deal
 

Hey,
I have a 300ce 24v with same problem.....I replaced the EHA valve, Idle Control Valve, the fuel pump/filter, the OVP fuse, and used fuel injection cleaner.....All these replacements helped the motor get to where it is---a whole lot smoother...but, i still have the warm start problem...usually takes between 2-4 attempts for the car to run....It starts each time but sputters to death....Something is definitely bleeding the injection system....most likely the injectors are leaking in my car....go figure....best of luck

a

The Best Solution!
 

Hey, I used to live there in the Lake Geneva area. One winter night, the wind chill factor made it 70 below, and I got called out to work. That night, nearly waist deep in snow, I found the solution! :rolleyes:

I got the hell out of there! I live next to the Pacific Ocean now and the coldest it gets is about 45 above at night! ;)

Not only does my car like it better, I do! :D

No more cold start problems. :thumbsup:

After all, I can fly in there in the summer to visit my mother and go to Hogs & Kisses for a long lunch. That and International Antiques, what else does it have to stay there for? :P

Replace the crankshaft sensor,it does not throw a code.