Pajero Owners Club of South Africa

Marius, you are correct. I did not think it through properly. The waste gate should prevent over boost on the 4M41, so my suggestion that this is behind the illumination of the "check engine light" does not make sense.

You are also correct that the EGR valve would be shut when the accelerator is pushed right to the floor in order to gain maximum power from the engine regardless of the NOx emissions and that this would then lead to the highest possible boost pressure in any case, so that it would not matter whether the EGR system is blanked off.

I think the effect that I mentioned would only occur in engines where a variable geometry turbo charger is used. The angle of the variable inlet vanes are typically controlled by the engine ECU. At high part load the ECU will take cognisance of the EGR valve opening selected and attempt to compensate for the loss in exhaust gas flow to the turbine (due to EGR) by selecting a high angle of attack setting for the vanes. If the EGR system is now blanked off the ECU would be unaware of this and the turbo could over boost. These turbo chargers typically don't have a waste gate, because they can be controlled via the inlet vanes.

Some time now since I had the EGR blocked off, so here are a few observations to date:

although not scientifically tested, it appears my fuel consumption has improved - I used to get on avg 450 km on a tank in town and now it is almost 500km

took the car for a longish drive the other day and the wind was really pumpng between Paarl, Swellendam and Malmesbury. The car just felt like it had more power at speeds in excess of 120km/h, against the wind. Not sure exactly what to do in order to be 100% certain abt this and would like to get some feedback / advise in this regard..? Was told that a dyno test on an auto is not preferred?

Was following a thread in the 4x4community thread about the use of two stroke oil for diesel engines...
what an overload of info! Problem is that I was almost convinced to go to 2SO (for reasons as mentioned earlier in this thread), but now I not so sure....Arguments listed on this forum claim some benefits like cleaning of injector tips carboned up, etc.

I still think that our diesel in SA might have a (significant) impact on the diesel fuel systems of our cars; maybe causing all these issues like loss of power, valve blockages, injector problems, etc...It is howvere just my gut feel.

If our fuel was good enough the suppliers won't support additives, but they do!

https://www.pajeroclub.co.za/forum/viewtopic.php?t=2471