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SDI EGR delete and gas flowing for more power.

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Thought I'd finally add the "how-to" which people keep asking about....

Old EGR systems jam up or just don't work once the car is over about 50k miles or 10 years.

The soot builds up and mixes with oil blow by droplets/fumes which mix together to form a sticky, gungy mess that is very difficult to shift (inside the engine). The backs of inlet valves get coated and coked up and inlet ducts get smaller and smaller reducing air flow. In a diesel engine, less air means less power. Also lots of hardened crud builds up right around the injector nozzles affecting the spray pattern. And because the ECU has no idea that the engine is clogged up, it still delivers the same quantity of fuel as if the car were brand new. So with excess fuel and not much air, the emissions suffer terribly, resulting in even more soot and lots of smoke from the exhaust. Clogging up the oxidising catalyst and subsequently an MOT fail. Even fitting a brand new air filter just before MOT time doesn't help, to try and suck in that last bit of fresh air.

There are three solutions to get the car running like new again-

1. Clean out the inlet system and decoke the cylinder head. Fit a brand new EGR valve. (BTW cellulose thinners works best to remove the black goop)

2. Clean out the inlet system- if you really want to- and disconnect the two vacuum hoses to the choke flap and EGR valve. That will help improve the system a lot. (block the vacuum pipes so nothing gets sucked in)

3. Clean out the inlet system, block off the EGR system, plug the exhaust gas inlet ducts to make the air flow more laminar, disconnect the choke flap vacuum pipe and divert the low oxygen sump gases away from the inlet. (my favourite solution for 15% more power and phenominal MPG).

Pics follow:

SDI EGR id.jpg

EGR flow.jpg

EGR loosen.jpg

Open plenum.jpg

inlet manifold.jpg

inlet duct.jpg

trumpets or ram tubes.jpg

gas ducts.jpg


ram side.jpg





EGR valve duct.jpg

breather pipe divert.jpg

Edited by mk2
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