E.G.R. Disconnect.

[EugeJK]

On the same token, you could unplug the solenoid/vacuum switch that links the EGR control hose with the engine vacuum pipe.

The only thing that really worries me is that once you eliminated the EGR (always off), the ECU still thinks it’s there. Let’s say for numbers’ sake, at the given mode, the ECU sets 80% air intake rate and 20% EGR rate. As the EGR is shut off, only 80% of air mass turns up in the cylinders. This is because the EGR pipe joins the intake manifold after the throttle intake. Could it be the case? What would that lead to? What do you think guys, MCJK and Davidd?

[davidd]

you have other engine sensors to monitor air flow through the engine including a map sensor in the manifold and an air flow sensor in the aircleaner. these would feed information back to the computer and the correction would be made by delivering more air via the throttle body. hasn't affected my vehicle as far as that is concerned.

[davidd]

oh, forgot, if you unplug the solenoid actuator on the rocker cover it throws a CEL on te dashbord.

[EugeJK]

Disconnected EGR by putting a block (bolt) into the valve control hose and observed the following:

- performance-wise almost the same, BUT a longer delay FROM cruising @1400-1600 in 2-4 gears (EGR supposed to be ON, but blocked) TO rapid acceleration.
- engine rattles more in any mode: cold start, warm start, cold idle, warm idle and shut down.
- sinusoidal rumbling sound appeared @ idle rpm. Not that loud to be heard (and if it’s still there) when cruising etc.

So I connected it back. I got '08 engine (engine code # VM49C). IMHO the ECU doesn’t compensate fully when EGR is missing; say it doesn’t add enough throttle intake when there’s no EGR. I reckon the EGR must be eliminated on the ECU level as well. Otherwise, no one knows what that would lead to in a long term.

PITTA but I have to live with it. With 10ppm sulphur diesel around, the engine still has longer live before clogged up, even with the damn EGR.

[davidd]

.......adaptive learning.........

[EugeJK]

Originally Posted by davidd

.......adaptive learning.........

did you mean us or the ecu?

[davidd]

the ecu i think...i'm beyond help