1KZ-TE rough idling

peter_Kzj78
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1KZ-TE rough idling

Postby peter_Kzj78 » Sat Apr 29, 2017 2:26 am

hi guys,
my engine is keeping me busy....
it falls into a very rough idling from time to time and I can´t tell why. no matter if cold or hot, could be anytime.
here is a clip https://www.youtube.com/watch?v=UgXXqxiCtc0
I had fitted a transparent hose because I have air in the fuel filter again. damn primer pump again. had to replace it in every toyo i had so far.
however, it will only suck air when the pump is pressed down and even then when you see air bubbles in the hose, the engine would not sputter and nothing.
so I would not dare to hope it has something to do with air.
i had my injectors changed 30 k kms ago.
i adjusted the pump to accomodate the intercooler with 1/3 turn in.
I very much believe the rough idling started only after fitting the IC but I really can´t recall. it got more obvious then because the IC was rattling against the hood until I adjusted the space.

i just returned from a trip to the Tunisian Sahara, did 4000 km´s and have to say it did great in the dunes. nice torque and the side exhaust comes in nicely. was working on my own dump pipe before the trip but didn´t dare installing it without being sure about the setup. the vibration of the engine idling let a welding seam break on my down pipe at the turbo flange when I was leaving the dunes and had it welded in the next village. but it´s again starting to crack and I am sure it´s about the vibration.

any recommendations?
thanks
peter

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kbushnz
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Location: Massey, Auckland

Re: 1KZ-TE rough idling

Postby kbushnz » Sun Apr 30, 2017 11:11 am

The fuel spill valve adjustment for when you did the intercooler could be the issue....
The 1/3 of a turn is a rough guide....And its a bush mechanics way to increase fuel delivery and not really the right way.
try and back it off a little and see how it feels....
Turn it in too much and it can rev away on you.....Or it wont start at all.

There is a black tuning box a local seller in NZ uses with great results.
Could be a good trick for you....
Talk to these boys....
http://www.kaiapoirepowers.co.nz/
They may be able to sort you out and get it shipped.
Cheers Calvin
KZJ78 Landcruiser Prado...

peter_Kzj78
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Posts: 61
Joined: Mon Jun 30, 2014 4:11 am

Re: 1KZ-TE rough idling

Postby peter_Kzj78 » Thu May 04, 2017 1:51 am

thanks Calvin! much appreciated!
will try working the spill valve and get in touch with the guys.
I was not successful with a chip tuning product myself.
had one from italy which was for VP44 pump while I have a Denso, long story.
sent it back and didn´t get exchange nor money back :-(

peter_Kzj78
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Posts: 61
Joined: Mon Jun 30, 2014 4:11 am

Re: 1KZ-TE rough idling

Postby peter_Kzj78 » Sat Jun 03, 2017 6:41 pm

just wanted to give a quick update what has happened so far...

i have replaced the stock diesel primer pump again but now to an aftermarket product used in dumpers or tractors. needed only a new bracket to mount it.
previously I had installed a check valve because I was tired of the fuel running back all the way to the tank. well, that turned out well in the beginning but unexpectedly the valve disintegrated and its guts went up to the hose and stuck before the filter. unbelievable, this was a chemical grade product...so this little piece of sh... blocked the way to the filter and combined with the again leaking membrane of the primer pump it was giving the stutter in idle.
well that was not all of it. also the U joint at the rear differential is done so that´s one reason why there was quite a "moving" response when shifting from N to D. but here comes my real problem now. the rear engine mount which sits underneath the transfer case dissolved itself and the rough idle gave it the shakes throughout the drive train. want to solve this now but.....I have automatic transmission A343F and all part diagrams show two different mounting options, one ATM one MTM but they go under the same part number 12371 67030, see vor yourself. anyone had to exchange that and can confirm if that number fits the ATM?
From time to time I source at this shop in the arab emirates, huge stock and selection and quite fair pricing. shipping can be a bummer though but the diagrams etc. are much of a help
https://partsouq.com/en/catalog/genuine ... j780030439

cheers
peter

peter_Kzj78
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Posts: 61
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Re: 1KZ-TE rough idling

Postby peter_Kzj78 » Fri Jun 09, 2017 8:05 pm

I received the right part engine mount. replaced it plus had a defective u-joint.
fuel system cleared from air leaks and engine runs smoother. still the vibrations in idle speed but now I can stop them when idling to 800-850 rpm instead of 1000.

I have now installed an engine oil cooler using an adapter plate for the oil filter and custom tubes with pressed fittings, mounted in front just behind the grill, will post that seperately.

didn´t do the spill valve reset yet but decided to go with a tuning box from Austria now. it´s a quite often used box under names of Kueberl and Chiptuning.at. got a nice deal for 400EUR. they are around for 20 yrs and have a good reputation. I will find out soon.

what I still could not figure out is what the stock power of my KZJ78 yr 1996 should be. since it was imported from Japan to UK and then to me in Austria, there is no original document and they went with data of the KZJ95. there are versions without intercooler with 123, 125 or 130HP, some claim the KZJ to be 130? anyway mine still feels like 80HP due to the ATM :-( maybe 90 HP since the IC and exhaust upgrade ;-).

anyone knows if the ECU in the KZJ78 is much different from the KZJ95? the tuning boxes are made for KZJ95 but I guess it shall work the same? it works mainly by changing injection timing and fuel/air mixture and should raise power from 125 to 146 HP and 295NM to 336 NM in it´s standard setting (level 5) and has a reserve for another 8 HP (up to level 9, each level 2HP).

cheers
peter

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tweake
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Re: 1KZ-TE rough idling

Postby tweake » Sat Jun 10, 2017 1:04 pm

peter_Kzj78 wrote:
anyone knows if the ECU in the KZJ78 is much different from the KZJ95? the tuning boxes are made for KZJ95 but I guess it shall work the same? it works mainly by changing injection timing and fuel/air mixture and should raise power from 125 to 146 HP and 295NM to 336 NM in it´s standard setting (level 5) and has a reserve for another 8 HP (up to level 9, each level 2HP).

cheers
peter

i suspect the later models will use a slightly different ecu. that due to the slightly different injection pumps.
i'm not sure when the change was but early ones have resistors on the side of the injection pump and later ones have eprom on the side of the pump.

peter_Kzj78
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Posts: 61
Joined: Mon Jun 30, 2014 4:11 am

Re: 1KZ-TE rough idling

Postby peter_Kzj78 » Mon Aug 07, 2017 8:08 pm

upgrade with chip box successfully completed, thanks!

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