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I just removed my EGR unit, replacing it with a £2 LR blanking plate on the manifold. Then replaced the top intercooler-inlet manifold pipes & tube with a single pipe. Job done and bit more space in the engine bay!
Sounds good to me. Where do I get a blanking plate from, and what exactly needs to be done to the intercooler manifold and pipes?
James,Just to add a bit of information..... The EGR valve mods won't have a huge effect on black smoke when you are accelerating hard off something like a roundabout.This is (usually) a symptom of turbo lag... On a diesel engine with all mechanical control like the 200 and most 300 tdi engines, the turbo is operated by the exhaust gas in the exhaust manifold. When you put your foot down hard, the injection pump throws a load more fuel into the system to make the engine go faster... because it is powered from the exhaust, and as such the boost is related to the engine revs, the turbo doesn't work any harder until the engine spins faster... so there is a slight delay in the boost increase as the engine comes up to speed. This is turbo lag... you often hear people talking about the turbo 'kicking-in'... this is when the boost pressure gets up enough to help the engine run faster and the power spirals upwards.Now.. in the time between you hitting the pedal, and the turbo spinning up, there is an excess of fuel in the system... not all of this fuel is burnt in the cylinders because there isn't sufficient air from the inlet system to match the increased amount.... this shows up as a sooty cloud of smoke from the exhaust.Hope that makes some sense !There are some funky ways to negate turbo lag.. but they are all quite expensive ;-)
There are some funky ways to negate turbo lag.. but they are all quite expensive ;-)
Thanks Tim, that makes perfect sense to me. Also explains why the car only smokes under exactly the conditions that you described. The rest of the time its fine after the initial startup. What causes the (smaller) plume of smoke when I first turn the engine over? Is it also unburnt diesel or is it oil?
So blowing down the snorkel doesn't work then ?well, there goes my reasoning for sticking my head out of the window :D
DOES A NON-CAT EXHAUST NOT FAIL THE MOT IF YOUR VEHICLES AGE REQUIRES A CAT?
Quote from: "MZ6666"DOES A NON-CAT EXHAUST NOT FAIL THE MOT IF YOUR VEHICLES AGE REQUIRES A CAT?Yes, but the likes of Rimmer Bros make a stainless sports system for the 300 TDi than goes from the Cat back so the cat remains in the system. The likes of my 1995 300 TDi had a cat fitted but is not of an age where it is required for the MOT on a diesel so when it needed replacing I had the non-cat downpipe fitted. Much cheaper option :D
That's worth knowing. Does that apply to all of 1995 (mine's an M) ?
The reason why the turbo doesn' repond to the increase in fueling is that it isn' exhaust gas that makes it spin. THe turbo spins as a result of heat,thats why it lags more when the engine is clock cold.