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Vaccum lines diagram

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Vaccum lines diagram

Postby Jorgji » Thu Dec 08, 2016 11:35 pm

hello everyone. I own a 1992 isuzu trooper 2.8 tdi with
an 4jb1 engine. i don't know why but my mechanic has switched accidentally or not some of my vaccum hoses and now my car is very sluggish all the time but even more when i go up hills and won't rev up or speed up. does anyone have the vaccum lines diagram, i couldn't find it anywhere? thanks.
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Re: Vaccum lines diagram

Postby geeves » Fri Dec 09, 2016 5:02 am

No diagram as such but the one that is wrong should run between the pipe between the turbo and manifold or intercooler if it has one and the top of the injector pump. If that one is damaged the pump doesnt add fuel when the turbo boosts. Result no power
Sanding your knuckles before starting work can help. That way you cant skin them
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Re: Vaccum lines diagram

Postby turnturn » Fri Dec 09, 2016 5:29 pm

Does the 4JB1 Trooper have the QWS valve on the exhaust? This may be partially shut or incorrectly activated?

Most likely as Geeves has suggested though is that the boost signal hose to the boost compensator on top of the Injector Pump is blocked or off. I'm pointing/touching where the boost signal hose connects to the Injector Pump in the picture below.
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Re: Vaccum lines diagram

Postby Jorgji » Sat Dec 10, 2016 2:22 am

That hose is connected, but i think the only option is to find another isuzu and check the lines
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Re: Vaccum lines diagram

Postby geeves » Sat Dec 10, 2016 5:35 am

there are 2 butterflys to check. First in the inlet systen above the turbo. Remove this one and seal the holes by putting the bolt back through. Silicon wont seal this as it is a high pressure area.
Second is in the exhaust just below the turbo. Ensure this one is open. I dont know if Albania gets cold. If not this can be removed and sealed as well.
Sanding your knuckles before starting work can help. That way you cant skin them
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Re: Vaccum lines diagram

Postby Jorgji » Sun Dec 11, 2016 12:54 am

I just check all the lines with a smoke machine, all the lines were ok, the butterfly over the turbo area connected to the intercooler works fine, but i don't know about the one in the exhaust if it works.Geeves yeah it's gets cold around -10°c but better cold than no power at all. I made a change to the lines according to a picture that i saw on google the hose from the intercooler was atached on one of the egr valve and not to the fuel pump.
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Re: Vaccum lines diagram

Postby geeves » Sun Dec 11, 2016 6:29 am

That would be the problem. The line from the intercooler carries boost pressure not vacuum and the pump uses this to know how hard the engine is running. I split this hose on 2 of my Isuzus and the power loss was dramatic
Sanding your knuckles before starting work can help. That way you cant skin them
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Re: Vaccum lines diagram

Postby Jorgji » Sun Dec 11, 2016 3:43 pm

Geeves without bothering you, can you make some photos of the vaccum nest, after changing the vakum line of the pump the car revs up but won't speed up.
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Re: Vaccum lines diagram

Postby geeves » Mon Dec 12, 2016 11:02 am

Sorry I dont have that vehicle any more
Sanding your knuckles before starting work can help. That way you cant skin them
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Re: Vaccum lines diagram

Postby Jorgji » Fri Dec 16, 2016 9:35 pm

Thank you everyone i found the problem and has nothing to do with the vacuum , it was the clutch.
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Re: Vaccum lines diagram

Postby nikobatino » Thu May 04, 2017 6:51 pm

goodday guys i own a 1991 isuzu trooper 4jb1t
can you help me with those vaccum line,i think some of the line were swapped by the mechanic, the idle goes down when i turn the ac on, it rattles like its going off
hope you can help me, thanks
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