Wicked issue with 4AC

[el_camino]

Hello guys, I am trying to build love to a good condition AE86 with 4AC and keep it original for the moment. 

There is not logical issue however and being out of ideas I am reaching out for help.

The cylinder one refuses to work, no matter what.

There is spark, a good one. Distributor revised.

There is fuel. Tried with different carb from working 4ac.

There is good compression on all 4 (12).

Valves have been adjusted 3 times and are in spec.

The car is running smooth on the other 4 otherwise, starts first try. Runs rich, I assume due to the not burned fuel in cylinder 1.

I am really out of ideas what to do next. Anyone had a similar problem and ideas for testing please?

 

 

Edited 9 hours ago by el_camino

[altezzaclub]

Tricky... So is the cylinder ID from pulling a spark plug lead off when running? Number one didn't drop the idle speed?

What were the compression readings?

Is the spark plug black or clean? Colours of the other 3?

..and Cyl 1 will fire a spark plug in its lead resting on the head?

 

 

[el_camino]

All leads are new and all spark plugs are new as well as the distributor cap. 

Indeed, pulling the cable off the cylinder 1 doesn't change the work of the engine, while pulling any off the others would nearly stall it (two cylinders left).

Swapping spark plugs or leads always keeps the first not firing. 

The spark plug on cylinder 1 turns wet and black. The one on #2 is rather black with a bit of brown, the others are rather brown 

Cold compression test reads 11.7 on #1 and 12 on the rest. Warm compression shouldn't be as far from this to the point to fully not ignite cylinder one.

Edited 1 hour ago by el_camino