1994 Toyota Hilux LN106 3L Excessive Smoke and Power Loss

[hiluxgalaxy]

Hey y'all! I just bought a 3L Hilux (no turbo), recently imported from Japan, two weeks ago, it's my first diesel and I already made some mistakes. I was driving out to Colorado and ran out of fuel on the Penna Pike (4 miles from the non-gouging station, because I didn't know there was no tank low light). The tow truck driver who came to bring me diesel convinced me to spray ether into the engine instead of bleeding the air, and I was naive/stupid enough to allow it (I'm still kicking myself). Before this, there was some black smoke coming out when accelerating hard, and sometimes when trying to maintain highway speeds (60-70 MPH) in 4th/5th gear. After, I sometimes have huge puffs of black smoke on cold start, when shifting into first. Driving through Iowa I was filling up at Casey's and could only maintain about 55 MPH, and I had added in LiquiMoly in Chicago. After filling up at a Shell, I was suddenly able to maintain 70 MPH, but that only lasted about 200 miles, and I haven't been able to since. Not sure if Shell fuel actually correlates with better performance, or that was just a fluke, because I haven't been able to recreate the effect. I'm also in Colorado now, so I'm not sure how much elevation has to do with it. Driving on the highway yesterday I lost even more power. If I started up a hill in third gear at ~40MPH, I couldn't accelerate at all and felt the engine was incredibly weak. There's also consistent smoke coming out (seems white, I can only see it at night by headlights behind me) when I'm at highway speeds.

The fuel filter was replaced about 1yr/8000 miles ago, the oil was changed two weeks/2000 miles ago (with 15W-40 synthetic, and a 90915-YZZD3 Toyota filter, which I found out is undersized), changed out the alternator, PS, AC belts as well. The gasket between the exhaust manifold and downpipe completely deteriorated, I ordered a replacement and am going to install when it arrives.

My current plan of action is to attempt to bleed the fuel lines, add an oil additive, drive a few hundred miles (is this a bad idea?), and get an oil change using Rotella T5 10W-30, and replace the filter with the correct, bigger 90915-40002 Toyota Filter.

Questions:
Strangely, during cold starts in the morning the engine seems to turn right over, but starting a warm engine (waiting for glow plugs), takes a few seconds of cranking. Any ideas why?

My understanding of bleeding the fuel lines:
1) Remove the fuel filter
2) drain it
3) refill it with diesel
4) reinstall it
5) Loosen all of the injectors one turn
6) start pressing on the hand pump on top of the fuel filter until fuel starts to come out at the injectors.
Are any of these steps incorrect? Am I missing anything?

Is there anything special I do to install the manifold gasket? Should I grease or oil it before installing?

What fuel/oil additives are recommended? Has anyone used FTC/FOC products or Fuel Ox and had success?

Does anyone know a trusty diesel mechanic in the Southwest (preferably near Denver) who has experience with these imported Toyota diesels? I want to get a compression test and find out if there are serious issues.

Has anyone purchased the gregory's or ellery's repair manuals? Thinking of buying one but they're gonna take a while to arrive... Has anyone used reliable-store's 1997 Hilux LN106 manual? Not sure if I should trust the site...

Any and all advice is welcome!!

I took a cold start video this morning but read that I can't share links and can't upload videos, so not sure if that's helpful or how to start it.

Cheers!

 

[drewgold]

@Rocky Mtn Hilux and @hiluxgalaxy Thanks so much for the detailed responses, very helpful. I’m still somewhat of a noob when it comes to Diesel engines but luckily read about the need for additives and have been using Power Service from day one for my 5L truck (about 10,000kms)

I’m keen to try both the Hot Shots and XP3. People rave about Power Service and it’s readily available but I can’t say I notice any real difference. May have to think about pulling the injectors, would be interesting to see what sort of shape they’re in after 90k kms+ of crappy North American diesel. Would be telling to see if Power Service helped with buildup at all. At the very least it’s hopefully still protecting the injection pump and cylinders from wear.

My black smoke is generally only with WOT or at higher altitudes. Nothing terrible so from the sounds of things it‘s ‘normal’. I notice if I let off the throttle slightly on the highway the black smoke stops so clearly just over fueling slightly at max output.

I’m meticulous about service and have been changing the oil every 5k kms with Mobil Delvac Synthetic (0w40 in winter and 5w40 in summer). Always use OEM filters. Been thinking 5k change intervals is overkill but from the sounds of things it’s good insurance for the 3L/5L engines.

Very seriously considering a turbo though. The above video mentions 30% being safe but I feel like even 15-20% increase would be more than enough for my needs. I don’t need to make crazy power, just want a cleaner burning engine with a little extra jam when I need it…

 

[Rocky Mtn Hilux]

One thing to remember about any of these additives. You will see a gradual improvement over time. Your engine will need a few tanks or more of driving for any additive to effectively clean up your injectors.

Additives only reduce the amount of black smoke exiting your exhaust, they don't eliminate it. Nonetheless, you should always use a good quality additive every single time you fill up.

Rocky Mtn Hilux

 

[drewgold]

@hiluxgalaxy and @Rocky Mtn Hilux Curious what you cruise at for RMPs on the highway? I'm at about 3k RPMs @110kph in 5th gear. Curious what gearing is like for other L series vehicles.

Also @hiluxgalaxy been checking out the other Hot Shot's Secret products. Have you tried the FR3 oil additive/friction reducer? I use Liquimoly Ceratec in a gasoline vehicle of mine and the results have been awesome. Liquimoly says that Ceratec isn't designed for use in diesel engines but have been on the lookout for a diesel specific additive. Curious about the FR3.

 

[Rocky Mtn Hilux]

The LN107 with a G52 gearbox (8" diff) has a 3.72 final gear ratio.

Cruising @ 110 kph in 5th gear my tach will read about 2500 rpms.

Max torque is produced @ 2400 rpm in a 3L.

It can go 130 kph or slightly more, but then my revs quickly go above 3000.

I have 31 x 10.5 tires. on 15" rims that hinders fuel economy and also messes with the final gear ratio.

Rocky Mtn. Hilux

 

[hiluxgalaxy]

@drewgold I also used power service and other additives soon after buying the truck and infinitely regret not buying a bottle of hot shots secret earlier. I haven't tried XP3 and don't know how it will compare, but you can buy hot shots really easily now, Walmart, tractor supply co, and basically all the auto parts stores sell them. Worth a try before you decide to turbo, although obviously that would make a much bigger difference. I agree with @Rocky Mtn Hilux, the fuel additives probably won't get rid of black smoke at WOT, but might give you a bit more range before you get there.

Curious what you cruise at for RMPs on the highway?

As if I have a tach I can send you a voice memo of the engine hum and see if you can decode the RPM redline to me seems to be around 30,45,72 kph in 1,2,3 gears, I can't remember if I've tried to push 4th above 110 kph, but my absolute top speed is 120 down a BIG hill. Might be able to maintain 110 in 4th or 5th on a really flat road (very rarely before I started using EDT, could barely ever use fifth gear), but I can cruise in 5th above 90-95 kph. 5th is pretty gutless at 90 though, acceleration is really gradual.

I thought there was a liquimoly product like ceratec for diesels?
I finally bought a bottle of FR3 a month ago but I only added it to the oil of a car I just bought (coincidentally another stick Toyota with no tach), so can't really tell if it's doing much. The Hilux is gonna be parked for most of the winter, I'm up in Alaska now. Might try it out in the spring to see if I notice any difference.
@Rocky Mtn Hilux have you ever found a block heater for them? Or have any experience starting them in extreme cold (-20°F or lower)?

 

[drewgold]

@Rocky Mtn Hilux have you ever found a block heater for them? Or have any experience starting them in extreme cold (-20°F or lower)?

I daily drive my truck (5L engine) all winter in the Alberta Rockies and have never had an issue with starting. My truck has dual batteries which I think helps. Coldest I have started my truck with no heating pads running is -25C (-13F). It had sat for three days and started first try. Didn’t sound very happy but it started.

I have an oil pan pad heater and a battery heater. Use both when I’m at home to try and help limit strain on the engine and batteries. I have started the truck at -38C (-36.4F) with the pad heater and it also started first shot. Pretty amazing for a diesel!

I have done a fair bit of research on block heaters and haven’t found anything definitive. There are frost plugs in the block that would theoretically work for a block heater but finding the right size and ensuring there’s enough room behind the frost plug is a big gamble. Would suck to pull a plug and then find that the block heater won’t fit.

I am seriously considering a reservoir coolant heater like a zero start or similar. There’s a coolant drain on the engine that could potentially be used as the inlet and then tie into the engine side of one of the heater hoses. Should provide good convection circulation if installed correctly. Can’t confirm 100% what the size/thread of the coolant drain plug on the block is and of course can’t check without draining all the coolant so haven’t gotten around to the dirty work of finding a fitting that will work. I can keep you posted if I do though!

 

[Rocky Mtn Hilux]

@drewgold I also used power service and other additives soon after buying the truck and infinitely regret not buying a bottle of hot shots secret earlier. I haven't tried XP3 and don't know how it will compare, but you can buy hot shots really easily now, Walmart, tractor supply co, and basically all the auto parts stores sell them. Worth a try before you decide to turbo, although obviously that would make a much bigger difference. I agree with @Rocky Mtn Hilux, the fuel additives probably won't get rid of black smoke at WOT, but might give you a bit more range before you get there.


As if I have a tach I can send you a voice memo of the engine hum and see if you can decode the RPM redline to me seems to be around 30,45,72 kph in 1,2,3 gears, I can't remember if I've tried to push 4th above 110 kph, but my absolute top speed is 120 down a BIG hill. Might be able to maintain 110 in 4th or 5th on a really flat road (very rarely before I started using EDT, could barely ever use fifth gear), but I can cruise in 5th above 90-95 kph. 5th is pretty gutless at 90 though, acceleration is really gradual.

I thought there was a liquimoly product like ceratec for diesels?
I finally bought a bottle of FR3 a month ago but I only added it to the oil of a car I just bought (coincidentally another stick Toyota with no tach), so can't really tell if it's doing much. The Hilux is gonna be parked for most of the winter, I'm up in Alaska now. Might try it out in the spring to see if I notice any difference.
@Rocky Mtn Hilux have you ever found a block heater for them? Or have any experience starting them in extreme cold (-20°F or lower)?

I have a block heater that keeps both my oil and my coolant warm in nasty winter weather and I cannot say enough good things about it. It makes a huge difference when starting your engine and I am able to turn on my heat within 2 or 3 city blocks.

Battery heater huh...? I like that idea.....

Cold winter starts are extremely hard on an old diesel engine. I once had to park my Hilux outside overnight when it was -40C without plugging it in. It started, but I honestly thought it going to explode. I would not recommend anybody trying this. I always carry with me at least 50 feet of cable to make sure I have enough cord to reach an outlet.

The two things you need to be cautious of in that kind of extreme conditions are your fuel freezing or gelling, and your oil freezing in your oil pan.

Xp3, Mobil 1 and my trick block heater are my weapons to help my Hilux survive Rocky Mountain winters.


Rocky Mtn Hilux

 

[COCruiser6080]

I just added myself to the hilux club and live up in the Colorado mtns in summit county. I have a LN107 3l and curious @Rocky Mtn Hilux what block heater you have?

Definitely noticed the power loss and black smoke up here at elevation and also when the petal is to the floor. Will be purchasing hot shots ASAP. Curious if there are any other tips/tricks for additional power? Lets just say getting her up here on I70 was an experience.

 

[hiluxgalaxy]

Welcome @COCruiser6080 ! Yeah that drive was downright scary for me with all the extra camper weight. I think one option is injection/pump tuning, but unless you're very mechanically inclined it's probably not going to be worth the money, and it's going to be almost impossible to find someone who knows how to do it on this engine, or willing to do it. I've heard that adding a turbo is night and day, @galaxy.overland on Instagram should be a good resource if you're interested in that. You may also be able to order a turbo from new zealand for cheaper.

There's a private mechanic in Boulder with a diesel cruiser, doesn't know anything about the 3L but seemed interested in helping me out. There's also a guy in Kalispell who runs back40imports, fairly pricey but seems to really know his stuff. Feel free to message me if you want their contact info.

Running hot shots, after flooring it and having lots of black smoke, it seems to take some more driving cleanly for the injectors to get cleared and performance to improve, so if you can avoid black smoke (I know that'll probably be hell up there), you'll enjoy better driving experience and MPG

 

[Rocky Mtn Hilux]

I just added myself to the hilux club and live up in the Colorado mtns in summit county. I have a LN107 3l and curious @Rocky Mtn Hilux what block heater you have?

Definitely noticed the power loss and black smoke up here at elevation and also when the petal is to the floor. Will be purchasing hot shots ASAP. Curious if there are any other tips/tricks for additional power? Lets just say getting her up here on I70 was an experience.

I don't know what brand of block heater I have on my Hilux. It was installed when I bought it.

I do know that it makes a huge difference when it's nasty cold outside.

 

[philb]

I have an LN108 hilux in Alberta, so very cold winters. I have a zero start circulating coolant heater. I have had zero issues starting it, even at -40C

 

[Miloslavich]

I own a '92 LN107 with the 3L,

View attachment 3150024

Hey what skid plate is this? any branding or writing on it? thx

 

[Miloslavich]

The LN107 with a G52 gearbox (8" diff) has a 3.72 final gear ratio.

you sure about this? 100%? My LN107 has. 4.10 final ratio from the factory..