380sl Air/Fuel Ratio VERY RICH after warmup

[Build]

Hi everyone.

We took a 1000 mile trip and along the way the car started running extremely rich, pouring black smoke. It runs perfectly until it's warmed up completely, or if is running over 80 mph it runs fine all the time.

It has 146k and had a complete tuneup, including all ignition, fuel pump, fuel filter, timing chain, guides, plus more, less than 10k ago.

Any ideas? We need to drive this back those 1000 miles. I have access to tools. All help is greatly appreciated. Thanks.

P.S. We're in Rowdie country so maybe he can say a few words or wave a magic wand? Thanks.

[abiby]

Originally Posted by Build

Hi everyone.

We took a 1000 mile trip and along the way the car started running extremely rich, pouring black smoke. It runs perfectly until it's warmed up completely, or if is running over 80 mph it runs fine all the time.

It has 146k and had a complete tuneup, including all ignition, fuel pump, fuel filter, timing chain, guides, plus more, less than 10k ago.

Any ideas? We need to drive this back those 1000 miles. I have access to tools. All help is greatly appreciated. Thanks.

P.S. We're in Rowdie country so maybe he can say a few words or wave a magic wand? Thanks.

WAG would be warmup regulator. There's a filter screen in the fuel line connector which gets plugged up. Also, you could have issues with the vacuum lines going to it.

And last, it could be shot. All just wild ass guesses.

...and Rowdie just TELLS everyone his wand is magic.

[rs899]

another WAG is your cold start valve is stuck on somehow.

[Build]

It runs so rough and black smokey, but perfect until warm. It seems that as soon as the temp sensor triggers the emissions, it starts dumping fuel in.

I'll check the wur again. Is there a way to bypass the computer circuit so it will think the engine is still cold and run smoothly?

Thanks for the ideas?