I have an 86 240DL, it has the b230F.

It starts fine in the morning, but misses, and then after a minute or so runs ok. It runs rich, you can smell gas and see black smoke. It also runs like crap, hesitates on acceleration and tries to stall. When you turn it off, it won't start again for a few hours. I have a new fuel injection relay, new AMM. Any insight would be appreciated. Thanks!

Try disconnecting the Oxygen sensor. It might be bad and sending a false lean signal. The car should run OK without it, for testing purposes.

Or it might be a bad ECT (Engine Coolant Temp) sensor telling the ECU that it's —35° outside. Testing procedure is in the 700/900 FAQ (same engine as 240).

The ECT is not easy to access for checking or replacing. An Ohmeter test is easier done from the ECU connecter.
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Bruce Young
'93 940-NA (current) — 240s (one V8) — 140s — 122s — since '63.

Had same problem with my 88' 240DL with b230f... after trying several solutions, it ended up being a problem with an old oxygen senson, which would explain why the car is running insanely rich and doesn't like cold starts. Good luck!

-Flup

It might be the fuel pressure regulator on the fuel injection rail. Take off the vacuum hose and smell for gas, if you smell gas it is likely a ruptured diaphram in the regulator. You can check fuel pressure if you have a gauge, if not just replace it they are about $35 -40 mail order. Good luck. Dan
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85 245 M46 194K, 92 245 A70 122K

How would I go about attatching the gauge, my friend has one and I'm not sure where to attach it on the fuel rail.

If there is not a fitting on the fuel rail it would have to be installed a the connection between the rail and the fuel line. Make sure the threads are the same on the gauge as your fuel fittings. Good luck. Dan
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85 245 M46 194K, 92 245 A70 122K