EGR blank

[TassieMav]

See, what I was thinking is take the valve/shinny thing (as you so elliquently put it) off, get a piece of steel cut to shape and bolt it all back on again with a steel plate under the valve/diaphram thing! EGR closed, ECU still things it's working. Problem solved? Or too simplistic?

[davidd]

check out the address below and look for inlet manifold. it shows the egr valve and diaphram as one item. the disc shaped valve seats into the manifold. very difficult to bolt a piece of plate in there.

https://octane.trademotion.com/sfima...net%2007JK.pdf

[davidd]

thought if you remove the valve, clean it up so it works and then disabale it in a way that the valve is jammed shut and then re-install it may be the easy way. then with vacuum line connected the ecu is fine. saves having to attach a small bottle to the end of the vacuum line, and saves any manufacturing of bits to block it off. anyway at least now you have something to work on.

[TheoB]

Originally Posted by Yom

I'd suggest regardless of the theory that it needs to be 100% tested before changing it because I know for a fact that when you block the EGR on the 3.0L TD patrol (also using a VNT turbo) and also the VW 2.0L Pump-Duse engine they will boost spike sometimes 10psi over what they're meant to run at.

Correct! With my zd30 egr blocked, and with a 3" straight thru exhaust, it went into limp mode when just cruising on flat hwy at 100-110 kmh under light throttle. That was when the ecu wants to maximise economy and somehow increases boost to compensate for less fuel...?? With less exhaust restriction now, it just kept increasing the boost until it tripped. So we had to "turn down" the VNC screw on the side of the turbo slightly, test run again until we got it exactly right. When done it drove excellent around town, on the tracks and on the hwy. With the egr blocked there was also no crap getting into the intake.
I guess this is where we are at the moment with the JK - can we do something similar or something very simple, without having to pull apart bits here and there..?

[TheoB]

Originally Posted by TassieMav

Well, as for the arguement whether to block or not to block, the fact of the matter is that the thing doesn't work anymore! lol And I wich it was as easy as the ZD30 to disable!

Wish it was as easy!!

[davidd]

i don't know how the turbo on the zd30 operates, many vehicles have a vacuum operated turbo . the jk turbo boost is operated electronically via the ecu and a stepper motor on the turbo. the software in the ecu sets the level of boost required under various conditions. the map sensor in the inlet manifold measures the actual boost pressure and feeds that information back to the ecu. so when you put your foot down, the ecu sends a signal for a prerequisite boost pressure, the boost controller on the turbo cranks up the turbo blades and the map sensor sends a signal to the ecu telling it what pressure the turbo is putting out. when the pressure the ecu wants has been achieved the map sensor basically informs the ecu and the ecu adjusts boost pressure via the boost controller on the turbo. there is no overboost , because the ecu controls the boost pressure in the manifold regardless of what else you do. the jk probably runs a different system to the vehicles you are talking about. the kj has a vacuum operated boost controller and that can be adjusted at the turbo too and put into overboost, but not the jk. does that sound right to you macca?

[Macca2801]

Originally Posted by TheoB

Correct! With my zd30 egr blocked, and with a 3" straight thru exhaust, it went into limp mode when just cruising on flat hwy at 100-110 kmh under light throttle. That was when the ecu wants to maximise economy and somehow increases boost to compensate for less fuel...?? With less exhaust restriction now, it just kept increasing the boost until it tripped. So we had to "turn down" the VNC screw on the side of the turbo slightly, test run again until we got it exactly right. When done it drove excellent around town, on the tracks and on the hwy. With the egr blocked there was also no crap getting into the intake.
I guess this is where we are at the moment with the JK - can we do something similar or something very simple, without having to pull apart bits here and there..?

Were the two done at the same time...ie dump pipe and EGR blank??
I can imagine the dump pipe effecting boost due to changes in airflow/spooliing and heat....but still not the EGR.

David has already done this and proved boost is not effected in the JK

As he correctly mentioned the boost is controlled by the ECM and unless there is sensor confusion there should be no doubt of the boost level and control.

This is semantics anyway...David has done it and there was no change in boost...later it was switched off with the new tune but initially it was just removing the vacuum to the EGR valve.

Personally if I had to do it...I would remove the EGR valve and fabricate a blanking plate behind it and then refit the EGR valve.

That way the switching circuit still operates but there is no path for the EG to get into the inlet manifold and it all looks original.

Matt.