egr system removal

[lambert]

I have been thinking, again.

 removing the egr system would be good as it allegedly makes engines run cleaner and thus give more mpg.

 however, would it need to go back on for the mot?

 at the mo without my catalytic convertor I get more than 5 carbons on the emissions test. if the lack of an egr system improves that to say 3 carbons then that would mean a pass on the mot?

 or am I confusing myself

[thermidorthelobster]

The EGR being PRESENT makes the engine run cleaner.  However, taking it off supposedly increases MPG / power, because you're sucking in clean air all the time instead of recycling it, although I've never noticed any difference.

My TD5 has been through MOTs with the EGR removed and hasn't had any problems.  The way I understand it, it won't make a difference to your CO2 reading, but removing it may make your hydrocarbons emissions go up.  That's why Japanese spec vehicles (where the emissions regs are tighter) have a more complex & thorough EGR.

[Drift]

On my isuzu 2.8TDI Ive two EGR valves, they where not fitted to the earlier 2.8's in the troopers but where added by VX at a later date following a ruling by good ole Europe over emmisions, this recirculates used exhaust gases back into the engine to burn a gas ( cant remember the name) this is not tested for on the UK  emmisions test.

This works well when the engine is new, but when the engine is older it can carbon up the inlets and it gets less efficiant and causes the car to smoke.

Ive blocked mine off to avoid this crud getting into my engine, had MOT's passed no problem.
Though some cars have the EGR mapped into the ECU so its not advisable to block them, but mine is a kind off bolt on idea.

Here is a piccy of my EGR valves when I blocked them, this stuff must act like grinding paste in the engine.

[bilge rat]

blocked mine off too. i just think what i would sooner breath . like already said all that crud getting re circulated through your engine cant be good. i wouldnt say i got any power gain what so ever from blocking it but it does run a lot smoother , noticed slight gain in performance whebn i removed the cat though...alan

[waveydavey]

EGR is to reduce the peak pressure and thus reduce NOx which are not tested.

Get rid of it, who wants soot in the intakes?

Aircraft are the problem for NOx, vehicles are not worth worrying about.