Mercedes 230sl burning fire thru muffler (see video)

[bebo]

Hi, has anyone had this situation with a Mercedes 230sl? I've uploaded video in youtube, sorry for the last upload, seems it had spam, here is the link, thanks in advance.

https://youtu.be/MUV7pbjFF-A

[Tyler S]

It is either severely over fueled or you have a multiple cylinder misfire. The fact that it is doing this on both tailpipes. Check your firing order and ignition components as well as timing. How about a little history on the car/repairs made?

[bebo]

The 230sl had a 900 km trip in 2012. No issues. After the trip, we had to clean the gas tank, we saw too much sediment. The car barely could travel 30 km before it started to drown and stall. We concluded that the fuel pump was affected too by the sediment. We got a used pump in ebay, new rotor, distributor cap, spark plug cables, fuel filter, injectors serviced, new spark plugs, condenser, you name it. The engine was rebuilt in 2009. It was running perfect until after the long trip. We have the car in a garage for 2 years, now we are trying again to see what we find. We got fresh fuel too. 

[bebo]

When the engine is idle, there is no explosion, no fire. But when you hit the throttle, it spits fire. We believe it could be the fuel pump.

[Tyler S]

So did this "Afterfire" start after replacing those components? There are 2 possibilities. The engine is either severely overfueled or there is an ignition component problem. Caps and rotors can be bad right out of the box. Try your old ones if you still have them.
Using a timing light, verify your advance is working correctly (easy cheap check). Check your points and dwell. A severely retarded distributor can cause this. Triple check your firing order. Start there and report back.

[Shvegel]

I have a suspicion your spark plug wires are in the wrong order.  Firing order is cast into the engine valve cover "Zundfolge 153624".  Start with the number 1(front) spark plug wire and check each one in a clockwise direction.  To the right of number 1 should be number 5 (5th from the front) and so on.