@ S Car Go

[NiftyNev]

Nev - definitely needs vacuum to close the valve on the 3.0. Lower pipe partially closes, lower plus upper totally closes.

Same as the 2.4 then.

I have a toyota pdf I can email you which also states egr does not operate at idle. I don't think its for any particular model though.

Will PM you about that sometime.

I was assuming that as you added exhaust gas to the mix you would have to lower the amount of intake air to allow room for the exhaust gasses to fit ?

Yep, exactly right.

This has been bugging me, so after some more thought and a better look at the venturi and manifold from a 2.4, it seems that I have been looking at things the wrong way.

The EGR it seems, has a direct path to intake manifold regardless of butterfly position and the amount of EGR introduced is governed by small butterfly position and of course, also depending on if the EGR valve itself is open. As small butterfly closes it allows less air to enter the intake so engine has to draw in exhaust gasses instead.

So cold test as in the manual says no vacuum to either which is correct. The 2.4 does the same.

Hot test says no vacuum to either at idle. This still has me stumped as my 2.4 gets vacuum to bottom port at idle when engine is hot. Small butterfly is partially closed. Also when off idle there is no vacuum to either port on mine (butterfly fully open) whereas the 3Ltr manual suggests there is vacuum to both off idle.

I need a stiff drink. Anyone want to shout as I have none here?

Nev

[wishbone]

Nev,

I've had a look at the egr.pdf I have and it seems it may be aimed at more complex motors. In this it states that as the exhaust back pressure changes it makes the vacuum strength vary which will vary the amount the small butterfly moves. Kind of like a feedback system.This has vacuum pipes attatching to the intake manifold aswell, which my surf doesn't.

I've been trying to work out exactly what's going on with the 3.0 - There is also a vsv on the bottom of the 'ufo' bit on the pipe that links the 2 manifolds. I'm assuming to actuate the actual egr valve.

This one is fed from the vacuum pump,same as the 2 vsv's on the throttle body.

I can't see any way for there to be a varied strength vacuum (no feedback system) - only 'on' or 'off' (unless the vacuum from the vac pump varies with revs ? )

Only way to be sure would be to put on 3 vacuum gauges, 1 for each vsv and see what they do.

Shame we can't find a manual for the 2L-TE isn't it ?

Rob.

[NiftyNev]

Nev,

I've had a look at the egr.pdf I have and it seems it may be aimed at more complex motors. In this it states that as the exhaust back pressure changes it makes the vacuum strength vary which will vary the amount the small butterfly moves. Kind of like a feedback system.This has vacuum pipes attatching to the intake manifold aswell, which my surf doesn't.

I've been trying to work out exactly what's going on with the 3.0 - There is also a vsv on the bottom of the 'ufo' bit on the pipe that links the 2 manifolds. I'm assuming to actuate the actual egr valve.

Yeah that PDF seems to be more advanced system. Yes, other VSV will be for the EGR Valve.

This one is fed from the vacuum pump,same as the 2 vsv's on the throttle body.

I can't see any way for there to be a varied strength vacuum (no feedback system) - only 'on' or 'off' (unless the vacuum from the vac pump varies with revs ? )

No, vacuum will be constant.

Only way to be sure would be to put on 3 vacuum gauges, 1 for each vsv and see what they do.

Yeah could do that. I am sure wnen I originally did tests on my RGR system, years ago now the EGR only got vacuum at idle. Will have to have a look at the lot again.

Shame we can't find a manual for the 2L-TE isn't it ?

Yep, that is one I would love to get hold of. Strange that they do not exist apart from the odd bit of info here and there.

Nev

[NiftyNev]

Bit of info here on the Injection Pumps and also the EGR System etc.

http://www.kovsh.com/media/library/2...%20P5ZGR01.pdf

http://www.kovsh.com/media/library/2...20AAC02V3D.pdf

Someone might want to put these links up somewhere as a Sticky.

Nev

[wishbone]

Nev,

Got my 3.0 running properly today. Seems I had a leak in the hard vac pipe between the vac pump and the vsv's at the other end. Hence the turbo not working and me messing about for hours trying to work out what was wrong....

btw a turbo gauge doubles as a vacuum gauge if you're desperate


Anyhow I've now taken a pipe direct from the vac pipe to the black vsv (the one closer to the middle of the engine ) and then put a T in from it to the 2 connectors on the throttle actuators. This works as it should and closes the valve at shutdown.

Next step is to find out where the leak is in the hard pipes and replace properly.

Cheers for the help,
Rob.

[NiftyNev]

Nev

btw a turbo gauge doubles as a vacuum gauge if you're desperate

Yeah, I always recommend a gauge with both boost and vacuum, so you can use it as a diagnostic tool.

Nev

[s car go]

Seems I had a leak in the hard vac pipe between the vac pump and the vsv's at the other end.

After reading this Rob I checked my "hard pipe",as my actuators seemed to do didley sqwat!! tops up my pipe was busted as well and nothing was working,so I, like you,ran a new length of hose over and hey presto the valves now snap shut at shutdown! Makes no difference at all to the way it starts,or how it behaves on the road. This truck always turns one or two turns before it fires,the 4 Runner before used to fire on a quarter of a turn. Maybe thats the diffference between electronic and mechanicle management???

Regards

Mark

[wishbone]

Hi Mark,

Now try re-connecting the original hard pipe. Mine is working now Weird - my turbo wasn't working at all, fitted the 'new' pipe from pump to vsv's. Turbo and vsv's start working. Swap back to original pipes and it all still works.

Will double check tomorrow.

Rob.