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EGR questions (3.1 TD 4jg2 or just in general)

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konni
Posts: 8
Joined: Sat May 17, 2014 6:39 pm

EGR questions (3.1 TD 4jg2 or just in general)

Post by konni »

Hello, i have some questions about the EGR system.

I have seen and read several of the other EGR threads without getting a full understanding of the importance of the EGR system.
Sorry if you think my questions are out there already.

I have a Trooper from -95 with the 3.1 TD intercooler engine
As to my understanding the EGR recycle some of the exhaust gases witch mainly results in reduced NOx oxides.
Some engines are built to have EGR valves from scratch.. Some engines are not built for it and therefore modified to have EGR valves later on, and comes eqiped with it only in certain countries.
Some engines will get a better milage with a working EGR system? Or have the milage not affected by the EGR.
The EGR keeps the engine cooler due to cooler combustion.
The EGR will get filled with sot and oil... And therefore not work eventually.

As of what i've read, the 4JG2 engine does not have EGR in several countries? Only in some countries where EGR is required by law.
This is why i seek information weather its a good idea to remove the entire system or not.

QUESTIONS:
So what i don't know is weather i can remove my EGR without hurting my engine or get worse fuel economy.
And if i do remove it, do i need to adjust my injection pump to compensate for the higher amount of oxygen? (timing and/or more injected diesel)
Will it affect the amount of sot in the exhaust (black smoke) ?

The reason for my urge to remove the EGR is a hassle with tons of vaccum lines, electrical vaccum valves, and in general clogged EGR system.
Also the possible gain in fuel economy and power.. IF it will result in that.

The alternative is to take it appart and clean everything and make it work... Why removing it seems as a much nicer idea.


If i made technical errors in my description please let me know. Im just a hobby mechanic after all.
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geeves
Posts: 1980
Joined: Mon May 11, 2009 1:56 am

Re: EGR questions (3.1 TD 4jg2 or just in general)

Post by geeves »

QUESTIONS:
So what i don't know is weather i can remove my EGR without hurting my engine or get worse fuel economy.
jury is out on this one. Mosty people that have removed EGR have done so because it may not of been working right so stat become meaningless. I would suggest a properly working egr makes little or no difference but can use some power. Certainly little or no effect on engine life

And if i do remove it, do i need to adjust my injection pump to compensate for the higher amount of oxygen? (timing and/or more injected diesel)
No change required

Will it affect the amount of sot in the exhaust (black smoke) ?
If anything it would reduce particulate at the expense of increasing NOS

The reason for my urge to remove the EGR is a hassle with tons of vaccum lines, electrical vaccum valves, and in general clogged EGR system.
Also the possible gain in fuel economy and power.. IF it will result in that.
Before doing so check your local emmissions rules allow this to be removed. Its common to remove in NZ and Aus but illegal to do so in UK and USA

The alternative is to take it appart and clean everything and make it work... Why removing it seems as a much nicer idea.
Not sure if valves are repairable They are expensive to replace
MUVIT
Posts: 136
Joined: Mon Nov 08, 2010 10:21 am

Re: EGR questions (3.1 TD 4jg2 or just in general)

Post by MUVIT »

when we removed the inlet manifold i couldnt beleive how much crap was in the 2 middle runners. A small garden hose wouldnt fit because 1 was blocked that bad.
Not 100% sure what caused it.
Egr deposits & turbo oil..
konni
Posts: 8
Joined: Sat May 17, 2014 6:39 pm

Re: EGR questions (3.1 TD 4jg2 or just in general)

Post by konni »

Thank you for good answers!

Since i live in Sweden i am required to have the EGR by law.
But since its often not working its not being controlled anymore :)
The exhaust values like CO, particle test etc is still being done, so i need to have those in order, where an EGR is handy.

However, i believe i will pass all tests without the EGR, so i'll likely plugg the system and keep the valves outside the plugs just for show.
If EGR would be super awesome it would have been installed on the engine in all countries all the time, and not only when required by law right?
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geeves
Posts: 1980
Joined: Mon May 11, 2009 1:56 am

Re: EGR questions (3.1 TD 4jg2 or just in general)

Post by geeves »

cost dictates on that one.
Look at recent and not so recent investigations of car makers.
GM Chevy etc in America failed to spend 57c on a modification to the ignition look that would of prevented the key accidently turning itself off from time to time killing the power steering and brakes. Over the 12 yeart period that this mod was needed 18 people died because of it. They have just been prosecuted and got the maximum possible penalty.
Not Just gm Ford are no better (some mght say worse) American made Ford Pintos had a bad habit of catching fire in rear end collision often killing everyone in both cars. Canadian made ones never caught fire. They had a fuel tank that cost $1.50 more to make.
Toyota have had similar problems as have Honda and Mitsubishi etc
konni
Posts: 8
Joined: Sat May 17, 2014 6:39 pm

Re: EGR questions (3.1 TD 4jg2 or just in general)

Post by konni »

Yeah, good point.
Are you saying that all engines might have had EGR if it wasn't for the extra cost?
It does clog the inlet etc, after all. So its not perfect.
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geeves
Posts: 1980
Joined: Mon May 11, 2009 1:56 am

Re: EGR questions (3.1 TD 4jg2 or just in general)

Post by geeves »

unclogging inlets is just normal maintenance Takes a long time to need doing. My wizard had working egr when the head was done at 200k Hardly anything in there
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