1984 500SEC with 265,000 miles w/origonal pistons and rings.

As I promised, my new injectors and seals arrived. Now this baby starts instantly. Cold, hot, sitting for awhile. Starts instantly. I am so excited to finally have this issue off my plate.

I did spend some money though. I started with new fuel filter, accumulator, pressure check valve at the fuel pump,new fuel pump,all new fuel hoses at fuel pump,new purge valve at charcoal canister, new vent valve at fuel tank,new injector seats, seals,and breather hoses.
I would have replaced all this sometime down the road. But oh well.

This did improve mileage a little. But hard starting hot continued to plague me. So I bit another bullet and bought a new set of brass injectors.
That was the icing on the cake. Fuel system stays pressurized. And startup is instant.

As Steve Brotherton suggested, I did have fuel pressure leaking internally. And in my case it turned out to be the injectors.

Can't wait now to see how my mileage will be.

Thanks Steve!!!

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Selling used Mercedes parts on Ebay...always changing...
cdplayer51 take a look!
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Congrats

So you were losing fuel pressure

Still can't see why it would start cold instantly & only lose pressure when hot?

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83 500 SEC Euro 198K

The cold start valve assists in cold starting your car by injecting extra fuel at start up. I under stand the valve energizes only while the starter is cranking. Then there is a sensor that tells the computor(not sure of the name of it now) to shut off the cold start valve.

On a warm start, the fuel system must retain it's pressure to get the gas to the injectors. The "cold start" valve is not used on a "warm start" situation.

In other words, the accumulator keeps the fuel system pressurized. But only if all other parts of the fuel system are doing their job. IE. the injectors. If they leak(sometimes its only one or two bad injectors) the accumulator can't keep up. And you are cranking and cranking to get the fuel back to the injectors.

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Selling used Mercedes parts on Ebay...always changing...
cdplayer51 take a look!
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that makes sense but I have no puter on a 82 so maybe its got a temp vac valve switch... so it could be lack of fuel rather than too much?

thanks...

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83 500 SEC Euro 198K