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3.1 Td bighorn qws

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3.1 Td bighorn qws

Postby Renier » Wed Mar 21, 2018 3:30 pm

Hi

Was just wandering if anyone is able to shed some light for me
I have just bough a 3.1td bighorn and there are 2 wires broken I believe they are for the quick warm sensor would this be causing any issues being open cuircuit or can it be left I feel the truck may be a little sluggish but have no previous experiance with isuzus to compare it withsome insight will be greatly apriciated
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Re: 3.1 Td bighorn qws

Postby tonkamu » Wed Mar 21, 2018 4:07 pm

QWS only works below 10 degrees and its a primitive system as the guru's on here will tell you. They will say throw it out! haha
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Re: 3.1 Td bighorn qws

Postby Renier » Wed Mar 21, 2018 5:06 pm

Can anyone direct me to a step by step to remove it?
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Re: 3.1 Td bighorn qws

Postby tonkamu » Thu Mar 22, 2018 12:58 pm

It wont make much difference if you remove it or keep it there with wires disconnected unless the physical flap post turbo is closing up when it shouldn't be. To really improve the system, the whole flange where the flap is for qws is should be replaced with a straight through downpipe.

Heres my thread when I was asking about QWS http://clubisuzu.com/viewtopic.php?f=19&t=7739&p=47398&hilit=qws#p47398
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Re: 3.1 Td bighorn qws

Postby geeves » Thu Mar 22, 2018 3:00 pm

not quite that simple.
Most of the above comments relate to the earlier 2.8 engine. The 3.1 needs and has a better system. The sensor is used to trigger the system which is controlled by coolant temperature. 2 Parts - the glow plug timer is very necessary on this engine as it needs to glow. The second part is to get a faster warm up and really only needed in cold conditions. This is a flap built into the exhaust roughly under the drivers seat. If this was stuck closed you would have very poor performance. Ive just had mine removed as part of an exhaust upgrade. Rarely needed in Wellington
Sanding your knuckles before starting work can help. That way you cant skin them
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Re: 3.1 Td bighorn qws

Postby Renier » Mon Mar 26, 2018 3:54 pm

Cheers greeves
So from what your saying remove the flap but keep the sensor if I'm not mistaken would it generate any issues with the wires that have come off some how or does it purely get triggered by the switch and won't create issues till it's activated
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Re: 3.1 Td bighorn qws

Postby geeves » Mon Mar 26, 2018 4:51 pm

If you look at it you will see its vaccum operated. Follow the pipes back to the solinoid and blank off the vac line there. The ecu will never know
Sanding your knuckles before starting work can help. That way you cant skin them
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Re: 3.1 Td bighorn qws

Postby tonkamu » Tue Mar 27, 2018 1:22 pm

Hey geeves, could you tell me what this is for. everyone tells me its the second waste gate but I thought it was the QWS flap for my 2.8. I really don't know.

The lever was attached to a large actuator that had a line running to all the vacuum solenoids that I removed.

wth.jpg
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Vehicle: 2.8 Mu 1991 All Black. MODS - Rear Lifted 2.5" Lovells Leafs / Rear Auto Locker / LSD in front / 33x12.5x15 MT Achilles / 9500 RUNVA w plug n kills switch inside cab / EGT, Voltage, Turbo timer, Boost gauge / 20 PSI VF10 Turbo with VF10 exhaust housing 2.5" downpipe with merged 2" wastegate pipe to full 2.5" straight pipe / GFB Boost Tap / Maxed fuel with grinded down cable stop / Adjusted Boost Compensator / 3.1 Oil Cooler / Intercooled / 3" Custom intake to sealed K&N airbox & filter to Snorkel / Catch Can / Xtreme Outback HD clutch / 80 amp alt / RockfordFosgate 300rms AMP w 2X Rockford Power 6x9's BT HDeck / all EGR, QWS, AC pump deleted.

Re: 3.1 Td bighorn qws

Postby geeves » Tue Mar 27, 2018 3:44 pm

I believe that is the qws in the exhaust pipe
Sanding your knuckles before starting work can help. That way you cant skin them
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Re: 3.1 Td bighorn qws

Postby Pasan » Sat May 15, 2021 12:58 am

Hi, any one got the vaccum diagram for 4JG2 QWS. Really need a diagram or a method to plug those vac lines. Thank you
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Re: 3.1 Td bighorn qws

Postby geeves » Sat May 15, 2021 8:58 am

plug all the lines that dont go to something you need.
Lines are
boost
intercooler to top of pump, turbo to waste gate
vac
alternator to brake booster alternator to several solenoids. Solenoid to fast idle, front diff via a canister on the chassis if you have the automatic free wheel. You may have vac lines to egr and qws
Cant think of any others
Sanding your knuckles before starting work can help. That way you cant skin them
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