DDK - Die Deutschen Klassiker

My 77' 911S came from California and still retains the Emission control / smog pump installed. Anyone in the UK have an understanding of the complexity to remove the said system should that be necessary? I only ask as yesterday on my first drive after winter hibernation, and after the engine had heated up, I experienced what can only be described as a pea souper fog explosion being pumped out, not only in the engine compartment, but also from the air vent in the front passenger side of the car !! To say I was alarmed is an understatement. Initially I thought there was a wiring burn behind the dash as what appeared to be smoke turned out to be exhaust fumes. After the panic of disconnecting the battery removing clocks to gain access and investigating the dash for melted wires, none were found. So off I drove.....within a few minutes we were back in full fog mode, with a definite smell of exhaust and oil. With the car running, the bulk of the smoke was coming from the pump in image 2237 with the air vent in the front screen adding to the fog. I must say there is a fair amount of oil on the bottom of the engine and transmission which will need investigating. So before I consider who might be best to investigate this aberration, as it's well beyond my pay grade, I was hoping for some thoughts on here. I'm based in Surrey, so persons in this neck of the woods who may be able to understand this system and do the work, i.e. S.E. would be preferable, should it be necessary to remove the Smog system. I'd rather not give it to a guesser, but ideally someone who may have deleted this system previously if that is necessary. TIA

Removal of the air pump and associated parts isn't complicated, but may not be the source of the problem. If you think it is then just remove the belt driving the air pump from the fan and see if anything changes. But given that you have exhaust fumes getting into your cabin via your heating and ventilations system I would think that one of your hear exchangers is leaking internally, probably due to rust

You will probably find leaking oil has found its way into the heat exchangers, and as that is being burnt off, as it is comes into the car. If you turn off the air flaps for the heat coming in, ( if they still function correctly) it may stop it getting into the car. Generally oil drips into the heat exchangers from the rocker cover gaskets, especially if the covers warp. Add to this the pipework in the heat exchangers have rusted through as mentioned above, and you will get all the symptoms as you describe?

Thanks fellas, that seems a probable reason. L

Just to add - it is unlikely that it is actually exhaust fumes if your heat exchangers have corroded - it’s the hot air being pulled over melting/evaporating oil. Still not pleasant but not as life-threatening.

For it to be exhaust fumes the actual exhaust pipe would also have to be leaking. Not impossible but the heater exchangers are relatively thin and the exhaust pipe passing through is pretty thick