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It's a Bosch system. Many European manufacturers used this system.
MB started using fuel injection in a car well before anyone else did, even while they were still offering cars with carburetors.
The injection system has lots more to offer in terms of mixture control and fuel distribution.
To solve the mixture control issues, and therefore emissions, the carburetor was becoming just too complex. The only thing they could figure out how to adjust mixture to was an O2 sensor, and even then those feedback carbs were a real nightmare. With OBD2 emission laws, you have to be able to shut off fuel to a cylinder with misfires, you can't (hardly) do that with a carb. You can't with this CIS injection system either, but at least it was a step in the right direction. I have wondered why they couldn't use the CIS injection system with a shut-off valve at each injector.
Even if the mixture issue could be fixed, you still have the distribution concern. You can control the mixture to each cylinder better with port injection like this, where each cylinder receives a dedicated amount of fuel, rather than a carb where all the fuel is mixed at a central location, then allowed to go where ever it wants. The closer cylinders receive a greater amount than the cylinders farther away, so then you have to make the mixture richer so the far away cylinders don't run too lean and misfire, which of course means the closer cylinders are running too rich.
Gilly
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