EGR Removal

[Albannach]

Does the ECU have to 'see' the EGR VSV?

[TonyN]

Good question. I don't think so, I've not had any CEL issues on leaving it disconnected.

You may get '2nd level' fault code, but it dosn't show as a fault when running or when doing normal fault code finding.

[BUSHWHACKER]

I wouldn't have thought so, 2nd gen and no doubt 3rd gen ECUs are a bit primitive. EGR valves are mostly vacuum activated, the electrical side to them is just solenoids that have a constant 12v supply.

[NiftyNev]

As far as I know the ECU senses throttle position via the TPS, which is what it gets the signal from to activate the VSVs for the EGR Valve and the Small Butterfly but as far as I know the ECU will not detect that a VSV has been disconnected or removed. I never disable the Small Butterfly VSV, because I don't believe it necessary and prefer to leave it operational for engine braking and for smooth engine shutdown. I also just block off vacuum to the EGR valve unless it's stuck open. Blanking plates fix this.

Nev

[NiftyNev]

EGR valves are mostly vacuum activated, the electrical side to them is just solenoids that have a constant 12v supply.

Electrically activated actually. Just a simple solenoid operated tap, to turn vacuum on and off.

Nev

[Albannach]

Cheers chaps.

I'll not bother re-fitting/positioning the VSV (didn't re-fit the EGR and pipework when I did the head).

[marcdtr]

Does the ECU have to 'see' the EGR VSV?

i think it is the same set up as the mr2 turbo rev1/2 alot of mr2 owners say that the ecu can be reset then it is self learning over a certain distance.This is not true it can only be reset to remove codes errors etc hence why they cannot remap the rev1 / 2 mr2s.The rev3/4/5 mr2s can be remaped and do see the ERG VSV but if you plug in you can turn this function off.Rev1/2 mr2`s need stand alone ecu`s to do anything.

[Sir Plug]

Does the ECU have to 'see' the EGR VSV?

I have no EGR system....removed it and threw it away. Have had no issues with fault codes, since.......