1989 mercedes 300 te flooding
 

i have a problem with the vehicle flooding after it gets warmed up and is turned off it is very hard to start and smokes out the exhaust and you can smell gas.please someone help........b rainey

I had a problem very similar to that. Disconnect the electrical connector from the cold start valve and see if that makes a difference.

Cold start valve does not operate when engine is warm.

Engine floods due to leaking fuel injectors.

They require replacement every 100K or so.

$36/ea plus seals

My cold start injector was, for whatever reason, dumping fuel into the manifold all the time when the engine was running or at least trying to. Once I disconnected it problem gone and no problem starting vehicle when cold.

Who told you all that?

Check the thread below. I think you will find it instructive.

http://forums.mbworld.org/forums/showthread.php?t=136398

Ron, have you corrected your problem?

I'd have to yes and no.


The car starts and runs perfectly with the electrical connector to the cold start injector disconnected. So yes problem corrected


I have not pursed, any further, trying to figure out why the cold start injector was doing what it was doing when the electrical connector was connected, because it doesn't make any difference. So no problem not corrected.

Your diagnosis is?

which one is it?
 

Is it difficult to describe the location of the "electrical connector to the cold start valve"? This would be helpful to an amateur like me.

Thanks in advance

When you take the air filter housing off, it's the only one that doesn't go directly into a cylinder. It also looks different than the other six.

I believe it runs into the 'valve cover side' hose of the Idle Control Valve (in front of the fuel distributor, standing in front of the engine)

When your car is "turned off" the electrical connection to the cold start valve has no electricity. Therefore, there's no injection unless that injector leaks a little. The leaking fuel, however, would just reside in the connector hose and not really get to enough cylinders to flood anything.

What is possible--and probable--is that your 6 normal fuel injectors are leaking residual fuel and flooding your engine. Several of the six will have direct access to an open intake valve of your stopped engine.

In normal use the cold start injector gets a short (< 10 sec) signal from the engine computer to function to help with cold starting. The engine computer gets information from a temperature sensor that verifies the engine is indeed cold. It seems quite unlikely that an electrical failure mode would result in continuous action of the cold start injector, but rather the opposite, i.e. no injection at all. But if it does, then the solution is to test the temperature sensor to determine whether it's telling the computer the engine is always cold. Even if it does, all that should happen is a rich running mixture and hardly a mixture so rich as to prevent starting.

You can chase this unlikely solution all you want, but you'll very likely come back to replacing six fuel injectors.

Of course, to verify flooding, try cranking warm engine with the accelerator pedal down about halfway or more.

Finally, with the cold start injector wiring disconnected, you'll move your starting problems to cold starting, too.

? for ikchris
 

89 300CE 181K

I have occasional start problems. But it will always start after about 5 seconds of cranking with the accelerator about halfway down.


does your suggestion above mean that I have leaking injector(s)?

Thanks

Somewhere Merc says that 4-5 seconds cranking can be considered normal. If your injectors are 181K miles old, an improvement could probably be noticeable. Replaced ours at ~140K and warm starting improved to close to immediate with no open throttle.