Hi folks.

Trying to clear a 16786 EGR Flow Excessive code. EGR valve renewed 2 yrs ago, so removed it and the connecting pipe to the throttle body for a check/clean with carb cleaner. A bit of carbon buildup but not excessive in my eyes, but EML still on so looking to disturb Throttle Body itself for a look-see/clean. Can i do this without disconnecting the wiring plug so as not to have to Reset the MassAirflowSensor/Butterfly (i don't have the kit - just a CodeReader)?

Ta.

Edited 5 July, 201213 yr by professor fate

DONT disconnect the wiring plug, leads to other problems,

PM me if you want the gaskets, I have several of them.

I thought that the car will carry out a readaption of the throttle body if you just switch on the ignition and leave it for 5 minutes or so, maybe try that out - if you have removed the air cleaner then you should be able to look down the throttle body and see/hear the flap being driven fully open and shut. Now if this happens, then you know that it will be able to perform readaption after you have refitted it. One other question, what is the engine code (ie model type).

Guide to do the adaptation of the throttle body........also the posts ont he subject below my guide answer most other concerns

http://www.briskoda.net/forums/topic/201016-how-to-reset-the-engine-ecu/

I thought that the car will carry out a readaption of the throttle body if you just switch on the ignition and leave it for 5 minutes or so, maybe try that out - if you have removed the air cleaner then you should be able to look down the throttle body and see/hear the flap being driven fully open and shut. Now if this happens, then you know that it will be able to perform readaption after you have refitted it. One other question, what is the engine code (ie model type).

It's a BBZ i think - 1 coil/cylinder. All i want to do is loosen the Throttle body (4 torx's) and lift it t check is the holes in the pipe underneath are clogged. I have a schematic that shows only a single seal (an o-ring?) under the body so i shouldn't need to replace that (hopefully).

The lower output is BBY and the higher output BBZ (75 or 100 I think).

Depending on the age of the car, the EGR valve pipe will connect to the inlet manifold directly or is earlier it will connect to an interface adaptor. If earlier there is a metal gasket between the adaptor and the throttle body and a "rubber" ring between the adaptor and the manifold. Problem I have is, if it is "low" EGR flow then it would/could be a block aperture at the manifold end - but logically an "excessive" flow sounds like the EGR is sticking open. Has the new EGR been adapted - or at least the engine ECU been forced to perform adaption after that EGR was fitted - also, is it a VAG or Pierburg(sp ?) EGR valve or a cheap pattern part?

Maybe it would be easier to remove the EGR pipe at the inlet manifold, remove its support screw and remove the EGR valve and see if you can blow through it - disconnecting its electical connector will not mean you need to perform adaption on the EGR - or maybe check that the EGR valves bottom plug has not been blown out or leaking.

Edited 7 July, 201213 yr by rum4mo

The lower output is BBY and the higher output BBZ (75 or 100 I think).

Depending on the age of the car, the EGR valve pipe will connect to the inlet manifold directly or is earlier it will connect to an interface adaptor. If earlier there is a metal gasket between the adaptor and the throttle body and a "rubber" ring between the adaptor and the manifold. Problem I have is, if it is "low" EGR flow then it would/could be a block aperture at the manifold end - but logically an "excessive" flow sounds like the EGR is sticking open. Has the new EGR been adapted - or at least the engine ECU been forced to perform adaption after that EGR was fitted - also, is it a VAG or Pierburg(sp ?) EGR valve or a cheap pattern part?

Maybe it would be easier to remove the EGR pipe at the inlet manifold, remove its support screw and remove the EGR valve and see if you can blow through it - disconnecting its electical connector will not mean you need to perform adaption on the EGR - or maybe check that the EGR valves bottom plug has not been blown out or leaking.

All my line of thinking, too, and all been checked/cleaned. The replacement EGR is stamped VAG and the price charged was oem... But, wonders of wonders, the MIL is now off, so the cleaning may have worked - but i have every confidence it'll appear again sometime! But the more i need to look at probs the more i learn, so all good, eh!! Cheers anyway...