EGR valve pinouts (egr cheater thread)

rabidh

Hi. Does anyone have the pinouts for the EGR valve (or a circuit diagram of the engine wiring loom with wire colours that might give some idea of the innards of it?). Are there any online resources?

(are there any vx220 engine circuit diagrams on the speedsterclub.nl online TIS info? I haven't found any 🙁 )

I was reading that the EGR valve contained basically a potentiometer and a motor, and it seems it should be quite easy to make an EGR faker (same kindof deal, but simpler than the O2 faker) for those with older ECUs (or without a friendly vauxhall mechanic)...

vocky

easier to just fit a new valve 🙁

rabidh

my EGR is fine - i just thought it'd be a nice way to bypass it if a small circuit would do the trick.

vocky

it could be done, when the ecu sends a voltage to the valve the potentiometer would need to alter the signal and vice-versa

vocky

I'm working on a box of tricks, will post results soon :roll:

I sliced up an egr valve today :shock:

vocky

my prototype egr valve notsure.gif

a few mods

ready to fit

on test :lol:

rabidh

Nice. Does it work?
So when the power is off the valve goes back to its original position? Its pretty impressive that all you'd need is a relay...

vocky

not sure if it works yet as the egr isn't always used by the ecu dunno..

my egr valve was duff, so nothing lost if it doesn't work :roll:

it's on test 🙂

I measured the resistance between the 'wiper' B and valve positions C+D, so required 1.5k ohms between pin B and the relay 'common' pin, I used 3 x 0.5 k ohm resistors (that's what I had laying around)

relay cost me under £2 from maplins (couldn't find a suitable relay laying about)

blanking plate took a couple of minutes to knock up from stainless plate 🙂

vocky

I'm still getting P0405 error codes 🙁

BUT I have plan B, which is a few changes to my 'box of tricks' :lol:

rabidh

You might be able to use a resistor/big capacitor to add some delay to the operation of the relay. Its a total bodge though.
Do you think that the EGR valve is on/off, or might it do various states inbetween?

vocky

plan B involves measuring a working egr valve :lol:

so plan A was doomed to failure :oops:

I will measure my vectra's egr valve 🙂

vocky

my vectra egr valve measures 2k ohms between B+C [valve closed] and B+D [valve open]

so changed the resistor to a 2k ohm...........still get P0405 once the engine is warm :evil:

Plan C begins .......... notsure.gif

rabidh said:
Do you think that the EGR valve is on/off, or might it do various states inbetween?

I'm wondering that myself, maybe it opens according to how much gases the ecu wants to allow through notsure.gif

luna_s

nice 😃 dont forget to post the diagram once youve got it sussed :razz:

vocky

plan C has been implemented :shock:

just got to wait and C :lol:

vocky

well plan C is another failure 🙁

haven't sorted plan D yet dunno..

but

plan Y is a Tech2 to hopefully switch off the egr system :lol:

and

plan Z is buy another egr valve if the egr can't be switched off :cry:

luna_s

boooo 🙁

vocky

I've not given up yet, to be honest I've not really put much effort into finding a fix :oops:

when I get the time I will have a decent look :lol:

vocky

this is the circuit

it appears the ecu wants a smooth signal from 0v to 5v when the egr valve opens

luna_s

wish i was some good at electronics, sadly not my strong point - i could ask a friend see what they say

h3ppy

electronics aint my strong point either, but i have done a bit.

wat about tryin a small capacitor to try and smooth out the voltage between switch over???

i really dont no anything about car electronics but as you said vocky it looks like it wants a gradual build up, not sure if a capacitor would sort this out or if i am talking a load of rubbish dunno..

maybe i should stick to wiring houses :lol: