Builds 1990 LJ78 in Montana (3 Viewers)

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Check the hose to the boost sensor on the intake, it can pop off and cause the engine to think it is naturally aspirated. Huge power loss is the result. If that is not the case you could take off the intake and see if there is any play in the turbo shaft. I would be really surprised if the turbo failed so soon; there can't be more than 8000km on it. Are there any funny noises?
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I can already see I'm going to need to get you on retainer AirHeadNut. Welp that hose was loose but popping it off and back on didn't seem to fix things. The turbo only kicks on when I'm flooring it and it's above 3000 rpm's. I don't hear any funny sounds but the boost gauge is reading a solid '2' constantly while we're moving.

When you say "take off the intake" you mean the large intake hose running from the air filter to the compressor right? Assuming that's what you mean I'll take that off tonight when we park or tomorrow before we leave. What am I looking for exactly? Testing to see if it "feels" like the shaft that connects the compressor to the turbine has snapped?

zomgthankyou for your help

-blivious
 
Can you tell if the turbo is spooling? If it is, check the intake system post turbo to see if there are any leaks. Also, check the boost line that goes to the gauge. Does the green turbo light come on when driving?

On the turbo, check that the shaft spins freely. There should not be much play in the shaft in any direction.

Apart from that, there could be an exhaust leak pre turbo, or, like @coldtaco said, the waste gate could be stuck open, letting most of the exhaust past the turbine blades.

The main thing is to start with the easiest things first.
 
that hose was loose but popping it off and back on didn't seem to fix things.

-blivious

Make sure you follow that hose all the way to the boost sensor and check all the vacuum connections along the path. Any one of them that has popped off will cause this problem. I've had the same problem a few times over the years.

Also check the hose to the waste gate on the turbo.
 
Sorry for the slow reply it's been a rough couple days of driving heh.

colorado:
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aaand Kansas:

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I started to pull the intake apart last night after we made it to Texas but the wife persuaded me to push through sans-turbo. As soon as we settle I'll check everything you've mentioned (thanks so much for the help). We did hear a "funny noise" yesterday morning that may have been turbo related. It was when we were first starting out on the highway. The noise kicked in about when the turbo would have normally. It sounded not unlike a cartoon waterfowl being choked to death, and it rose and fell in response to the gas pedal. It resonated through the drivers-side dashboard so strongly that it sounded like it was coming from inside the dashboard, or maybe from the brake booster, but given we've been having turbo problems and the turbine is located right in that area I assume it was related.

In answer to your questions:
- I don't know if it's spooling or not (how could I test for that).
- The green turbo light does come on when I floor it, but I never get more than 5psi of boost.

We have about 5 hours until we're home. I have to stop and work a bit in amarillo, but we should be home late tonight so I'll be able to start poking at this in earnest tomorrow.

Thanks again!
 
Sorry for the slow reply it's been a rough couple days of driving heh.

We did hear a "funny noise" yesterday morning that may have been turbo related. It was when we were first starting out on the highway. The noise kicked in about when the turbo would have normally. It sounded not unlike a cartoon waterfowl being choked to death, and it rose and fell in response to the gas pedal. It resonated through the drivers-side dashboard so strongly that it sounded like it was coming from inside the dashboard, or maybe from the brake booster, but given we've been having turbo problems and the turbine is located right in that area I assume it was related.

Thanks again!

That noise could be a big boost leak. Would explain a lot. Check the pipe/couplers/clamps that connects the turbo to the intake manifold.
 
So FINALLY got a chance to pop the hood today and I'm pretty sure my wastegate actuator is bad. It will no longer seat itself in the bracket and just hangs loosely like so:



I removed it, thinking that maybe it had slipped off the gate somehow at the stem, but no, it was attached fine, but there is a hole in the top of it. When I blow air into the hose nozzle, air comes out of this hole in the top. I'm not a certified mechanic, but that doesn't seem normal does it?

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I still have the old turbo with waste gate, but it is preset at 10psi and is not adjustable. Something like this would probably be better: ct20 waste gate | eBay

It looks like both the aftermarket adjustable ones and stock ones are available.
 
So basically 100% of the parts on ebay are shipping from China. I don't have anything in particular against china but I'm new to this, so just making sure that ordering aftermarket parts from china and throwing them in there is a generally accepted practice. Should I buy two of everything? heh.
 
So basically 100% of the parts on ebay are shipping from China. I don't have anything in particular against china but I'm new to this, so just making sure that ordering aftermarket parts from china and throwing them in there is a generally accepted practice. Should I buy two of everything? heh.
I can only speak for myself, but I haven't had any issues yet with parts ordered from China, Malaysia or Dubai. Yet is the operative word though
 
So basically 100% of the parts on ebay are shipping from China. I don't have anything in particular against china but I'm new to this, so just making sure that ordering aftermarket parts from china and throwing them in there is a generally accepted practice. Should I buy two of everything? heh.

If you need the truck to get moving for the time being you could wire the waste gate closed. LIkely you don't have enough fueling to stress the turbo too much. I'm running the same turbo at 17psi intercooled which is equivalent to 22psi not intercooled.

You could also look round for a used waste gate if you don't trust a new china one. There are a few JDM used parts outfits here in Canada that could likely send you one. I've dealt with Barry at this place and he is very trustworthy: J Cruisers JDM Parts and Vehicles for Sale in BC Canada
 
If you need the truck to get moving for the time being you could wire the waste gate closed. LIkely you don't have enough fueling to stress the turbo too much. I'm running the same turbo at 17psi intercooled which is equivalent to 22psi not intercooled.

You could also look round for a used waste gate if you don't trust a new china one. There are a few JDM used parts outfits here in Canada that could likely send you one. I've dealt with Barry at this place and he is very trustworthy: J Cruisers JDM Parts and Vehicles for Sale in BC Canada

Can the stock waste gate be adjusted for higher boost, or would it need a boost controller instead? It looks like there is a hole in the waste gate actuator that is allowing pressure to escape, so the hose would have to be unhooked and plugged. The new turbo came with the waste gate set at around 16psi, but the over boost light only came on once while I had it.
 
I feel a bit remiss that I haven't updated this thread in so long, but we had a great year with this truck. We named him 'sosuke', mounted a roof tent, built a pull-out kitchen and drove him across the US three or four times. He made it as far east as st louis, as far north as the yukon, and as far south as texas.

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At some point in the spring of 2017, while crawling along in the wyoming high-desert on the shoulder at 20mph -- the egt meter at 950 as 18 wheelers blasted by inches from the passenger window, we decided we needed to lose the 2lte. So we parked the truck at a vendor with a great rep in these forums and waited. 13 excruciating months and too many thousands of dollars later, Souske now has a 13bt/a440. We picked him up last week, and are currently trying to get back on the road with him, but we are having some air-in-the-fuel problems, which you can read about here: 13bt rough idle, sometimes wont start
 
That is awesome! I'm glad you have gotten good use out of it. The 13BT sounds like an excellent swap, I hope you can get the starting issues figured out soon and start to enjoy it again!
 
You're so cool AhN.. if I had half your diesel chops I'm sure I'd have been on the road last week. In three months when you get bored of that perfectly running TDI Prado, do me a solid and DM me before you throw it on craigslist ;)
 
I feel a bit remiss that I haven't updated this thread in so long, but we had a great year with this truck. We named him 'sosuke', mounted a roof tent, built a pull-out kitchen and drove him across the US three or four times. He made it as far east as st louis, as far north as the yukon, and as far south as texas.

53ShpwB.jpg


At some point in the spring of 2017, while crawling along in the wyoming high-desert on the shoulder at 20mph -- the egt meter at 950 as 18 wheelers blasted by inches from the passenger window, we decided we needed to lose the 2lte. So we parked the truck at a vendor with a great rep in these forums and waited. 13 excruciating months and too many thousands of dollars later, Souske now has a 13bt/a440. We picked him up last week, and are currently trying to get back on the road with him, but we are having some air-in-the-fuel problems, which you can read about here: 13bt rough idle, sometimes wont start


I hate to ask you but you spent thousands of dollars on a used engine and installation and it doesn't run correctly? That's ok with you? Would not be ok with me.
 

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