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4GJ2 vac lines diagram

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GreenHorn
Posts: 1
Joined: Sat Feb 12, 2011 9:47 am

Re: 4GJ2 vac lines diagram

Post by GreenHorn »

When I got rid of the egr, most of the vac lines where removed including the the ac advance. What was left was the turbo boost to injector and brake res to vac pump circiut. With the aircon vac line removed it, made very little noticable difference to the 3.1 when air con is on when waiting at traffic lights. Butterfly in the intercooler inlet is long gone and so has the exhausted cold start valve (been replaced by larger new exhaust pipe when the original muffer rotted out) so all the vac plumbing for these are not needed. Been like this for about 5-6 years now.
Captcol
Posts: 43
Joined: Sat Mar 06, 2010 9:18 pm

Re: 4GJ2 vac lines diagram

Post by Captcol »

When my engine is cold the ac idle up is good otherwise i get the bonnet vibration at the intersections, but it is not necessary just nice. I have disconnected the vac to the butterfly thing on the turbo side of the intercooler as I have no idea what it does and if it is supposed to have full time vac or what, or how I can remove it without causing leaks.
MU31TD
Posts: 10
Joined: Sun Jan 10, 2010 1:16 am

Re: 4GJ2 vac lines diagram

Post by MU31TD »

"The vac to the butterfly thing on the turbo side of the intercooler" works together with the exhaust brake for cold start, as far as I know. But it is not needed really in Australia. Point (B) may be left out. No need to block it. I've removed the solenoid (B) on my mate's car completely since I've posted this diagram above.

There is nothing wrong the way it is on the diagram. However you can ignore solenoid marked (B). This way vac line will go from (A) to (D).

Note: Not all engines are equipped with the boost controlled fuel pump. (It allows more diesel with higher boost). Some engines may not have actuator (D) at all! Instead there is another automatic controller that works when altitude changes.
MU31TD
Posts: 10
Joined: Sun Jan 10, 2010 1:16 am

Re: 4GJ2 vac lines diagram

Post by MU31TD »

I have a stock standard 3.1TD MU in the workshop at the moment. If I get a chance I can draw a diagram and mark all the vac lines as where they go and what color they are marked.
johneeewalker
Posts: 1
Joined: Fri Oct 30, 2015 5:57 am

Re: 4GJ2 vac lines diagram

Post by johneeewalker »

I have a 95 bighorn 4gj2 3.1td.... Coming from vacuum pump on alternator there are two Vac lines. One is fat and one is skinny. The fat one goes to the brake booster. The skinny hose has come disconnected and i cannot find where it goes to. Can anyone help?
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geeves
Posts: 1980
Joined: Mon May 11, 2009 1:56 am

Re: 4GJ2 vac lines diagram

Post by geeves »

It goes up between the alternator and engine and connects to one of the hoses going across the front of the engine.
From there it feeds into several solinoids for the EGR the air con fast idle the SOTF if you have it etc
Dreti
Posts: 1
Joined: Sat Oct 31, 2015 11:29 am

Re: 4GJ2 vac lines diagram

Post by Dreti »

Hi.
My lines are all disconnected because mi lasted mechanic.
anybody have a manual for the vacuum diagram for all the lines
Sjgreer
Posts: 1
Joined: Sat Jan 16, 2016 3:29 am

Re: 4GJ2 vac lines diagram

Post by Sjgreer »

MU31TD wrote:Or a hand drawn diagram can also do the job
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