yeah sorry, the jeep in question is 1993 LJ78 2LTE, have it 2 years & has been thick black smoke since i got it, I put intercooler on (Big size) & also did the boost up to 15 psi with electric fan with adjustable switch etc... loads of power and running great... just this thick black smoke at start up .. not at idle , but when I rev to drive away from stopped ... really is a huge cloud of thick black smoke on a non windy day ( shocking to see ) please Note NEW INJECTORS NEW GLOW PLUGS, NEW COOLER SYSTEM NEW TIMING BELT PULLEYS FILTERS OILS, starts on the button etc.. all the Mods were only done the last month to try get to the bottom of this issue. I even tried rotating the pump alittle & made no difference smoke wise... now running the pump back at the normal factory position. sorry & just removed the small throttle plate last week. really cant see what the next step is, any help would be great.
LJ78 Smoking
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I forgot to mention... the black smoke is not there once the jeep gets into 2 gear in the autobox, hmmm hard to explain, really feels like savage turbo lag as there really is loads of power with the boost set @ 15psi or its like what you said way to much fuel... what you think is next step, will I go ahead n take of the big throttle plate like I did with the smaller 1 last week.
GTSSportCoupe
2LTE abuser
It could be any of a few things. Has your injector pump been rebuild or changed in any way? There are calibration resistors on the side of the pump, to match the pump's characteristics to the functions of the engine computer (ECU). If these resistors are mis matched to the pump, it can cause smoke issues. I know because I've played around with them. Also, check to see if the little cap has been pulled of the Spill Control Valve (it's the thing sticking up from the pump head - above where the injection lines come out). If the cap is off, likely someone has cranked the fuel there. This could also cause black smoke, but is less likely. If it turns out to be one of the calibrations resistors, you can cut the wires where they go into the ECU, and install a potentiometer. You can use it to tune your fueling. If it is the Spill Control Valve, you can reduce the fuel again. I can explain how to do a lot of this stuff if you need help.
For the time being, use your right foot to regulate the fuel to try to reduce the black smoke as much as possible when you are not in boost. And also, watch those EGTs. Do you have a pyrometer? If so, what temperatures are you hitting?
Maybe try pulling the codes from the ECU? I can direct you to instructions on how to do this if you don't know. Finally, some guys have had capacitors leak in the ECU. Slim chance, but it could cause this problem too.
For the time being, use your right foot to regulate the fuel to try to reduce the black smoke as much as possible when you are not in boost. And also, watch those EGTs. Do you have a pyrometer? If so, what temperatures are you hitting?
Maybe try pulling the codes from the ECU? I can direct you to instructions on how to do this if you don't know. Finally, some guys have had capacitors leak in the ECU. Slim chance, but it could cause this problem too.
Ok here we go, I went ahead last night and made a start to remove the big plate venturi, yah the 2 screws are flat on the outer side so need to take the unit off and drill out the screws, I wasn't set up for it so I put all back together & had a look at the spill control valve.
First I noticed is that someone was at the turn screw no cap on top, so I said sure ill loosen it and give it a turn (clockwise). started the engine & revved up still black smoke so turned off the engine & gave the screw another few turns(clockwise), started the engine same again black smoke, at this point I said hmmm I should turn it back (anti clockwise) see if it makes a difference... when doing so I turned it clockwise with out thinking & went to start the engine & the engine runaway 0ooooooo man the revs FULL TROTTLE all on its own I grabbed a rag to hand in tried to cover snorkel, no success... jumped in the engine bay ripped off the air intake cover n pulled the k&n filter out, stuck my t-shirt in the intake pipe few seconds n she stopped, n the process because I stopped the airflow to the turbo just before the turbo the engine was gasping for air, it tried to turn the alloy intake pipe inside out going to the intercooler. spend 2 hours replacing the pipes.
Engine was at full throttle for about a minute... feck in hell lads the smoke in the garage, thanks to the electric fan install the fan stayed on for 20 minutes bringing the temp back.
So just for any of you out there that are planning to make a few mods regarding spill control valve adjustment ( don't turn it clockwise to much ) unless to want to clear every milli micro nano of carbon from the engine
mine has got clean whistle of life for sure for sure.After all that excitement pipes replaced I adjusted the S.C.V. screw back to have way (ANTI CLOCKWISE) drove it home last night felt fine not as much smoke. this morning when I drove off there was not as much but enough smoke, so I will adjust it another turn anti clockwise on the way home tonight & see the result in the morning startup.
GTSSportCoupe
2LTE abuser
Ok here we go, I went ahead last night and made a start to remove the big plate venturi, yah the 2 screws are flat on the outer side so need to take the unit off and drill out the screws, I wasn't set up for it so I put all back together & had a look at the spill control valve.
First I noticed is that someone was at the turn screw no cap on top, so I said sure ill loosen it and give it a turn (clockwise). started the engine & revved up still black smoke so turned off the engine & gave the screw another few turns(clockwise), started the engine same again black smoke, at this point I said hmmm I should turn it back (anti clockwise) see if it makes a difference... when doing so I turned it clockwise with out thinking & went to start the engine & the engine runaway 0ooooooo man the revs FULL TROTTLE all on its own I grabbed a rag to hand in tried to cover snorkel, no success... jumped in the engine bay ripped off the air intake cover n pulled the k&n filter out, stuck my t-shirt in the intake pipe few seconds n she stopped, n the process because I stopped the airflow to the turbo just before the turbo the engine was gasping for air, it tried to turn the alloy intake pipe inside out going to the intercooler. spend 2 hours replacing the pipes.
Engine was at full throttle for about a minute... feck in hell lads the smoke in the garage, thanks to the electric fan install the fan stayed on for 20 minutes bringing the temp back.
So just for any of you out there that are planning to make a few mods regarding spill control valve adjustment ( don't turn it clockwise to much ) unless to want to clear every milli micro nano of carbon from the engine
After all that excitement pipes replaced I adjusted the S.C.V. screw back to have way (ANTI CLOCKWISE) drove it home last night felt fine not as much smoke. this morning when I drove off there was not as much but enough smoke, so I will adjust it another turn anti clockwise on the way home tonight & see the result in the morning startup.
You shoulda asked me for some pointers, haha! I've been there. Only took 1 turn in (more fuel) for the engine to go into run-away. All you have to do to stop it is turn the screw back out while it's revving like hell. It's scary. I usually tell people only turn it in 3/4 turn MAXIMUM!!
Sounds like you've figured out your problem though. Someone screwed with your fueling in the past. Just adjust it small amounts at a time.
Also, you might want to check your engine oil carefully for bearing bits (sparkly pieces). Make sure that there was no damage to your engine when it was revving like that.
Yeah thanks I should check the oil tomorrow too. cheers for the reminder, regarding to just turn back the screw ... every time I adjusted it I locked the nut just to hold it in positon as it is very loose, jesus even if it was loose... the noise from the engine really felt like it was going to blow up going in that close ... Naaaaaaaa id rather sit back & enjoy the show
I have turned it maybe 6 full turns now anti clockwise & all I seem to be getting now is lots of boost with tiny less more power, I wonder will I get 30mpg hmmm interesting... ill turn it back alittle more in the morning after I do an oil check for the shiny stuff, fingers crossed
GTSSportCoupe
2LTE abuser
Yeah thanks I should check the oil tomorrow too. cheers for the reminder, regarding to just turn back the screw ... every time I adjusted it I locked the nut just to hold it in positon as it is very loose, jesus even if it was loose... the noise from the engine really felt like it was going to blow up going in that close ... Naaaaaaaa id rather sit back & enjoy the show
I have turned it maybe 6 full turns now anti clockwise & all I seem to be getting now is lots of boost with tiny less more power, I wonder will I get 30mpg hmmm interesting... ill turn it back alittle more in the morning after I do an oil check for the shiny stuff, fingers crossed
I didn't even know you could turn the screw that much! Really all adjustments should be able to be made in one turn at most. I don't think that is your problem if turning it that much made so little difference.
So other than the calibration resistors, maybe your boost sensor is not working? If it was telling the computer maximum boost all the time the computer would add maximum fuel for a given rpm.
If you want to try pulling codes from your computer, here are the instructions: http://toyotasurf.asn.au/techsite/downloads/DiagnositcTroubleCodesandPossibleCauses.doc
Lots of other good troubleshooting stuff here: Dowloads & Articles
ok so here we go... I adjusted the S.R.V screw anti clockwise all the way till if stopped .... and the smoke reduced alittle... after driving it for the day I noticed a tiny drop in power not much but alittle, so I screwed it back CLOCKWISE 3 full turns & then I drilled out the 2 screws holding the big venture plate on the intake system & removed it, started it up Taaaaa Daaaaa smoke gone
Now over the next few days I will turn the spill realise or control valve in (CLOCKWISE) alittle bit each day like you said 1/2 or 3/4 a turn drive it for a while n see can I get more out of the girl with out getting the cloudy black smoke again.
(P.S) old TSHIRT in hand just incase
where is the boost sensor located ? actually a mate has the computer to check the engine for these codes ill give it check with this first n see if anything comes up.
GTSSportCoupe
2LTE abuser
ok so here we go... I adjusted the S.R.V screw anti clockwise all the way till if stopped .... and the smoke reduced alittle... after driving it for the day I noticed a tiny drop in power not much but alittle, so I screwed it back CLOCKWISE 3 full turns & then I drilled out the 2 screws holding the big venture plate on the intake system & removed it, started it up Taaaaa Daaaaa smoke gone
Now over the next few days I will turn the spill realise or control valve in (CLOCKWISE) alittle bit each day like you said 1/2 or 3/4 a turn drive it for a while n see can I get more out of the girl with out getting the cloudy black smoke again.
(P.S) old TSHIRT in hand just incase
where is the boost sensor located ? actually a mate has the computer to check the engine for these codes ill give it check with this first n see if anything comes up.
Right on! Boost sensor is located on the left hand side inner fender. It has a vaccum line that goes through a little filter to the intake manifold. It's probably fine from the sounds of it now. The computer is the old OBD 1 system, so not sure if a modern reader will see the codes or not. What I do is jump the T1 to the E1 connector in the diagnostic box (also on the left hand side inner fender). Makes the check engine light blink. You just have to match the blinks to codes. If there are no codes I think it just blinks on/off constantly.
update regarding the turnscrew... I turned the screw with the engine running clockwise until the engine started to pickup alittle & then tunred it anticlockwise 1/4 turn,that seems to be her sweetspot plenty of power with bucket full of boost n very little black smoke... great result
We put it on the diagnostics and it is showing up that the timing is out... I checked the belt and all it fine right position etc.. BUT at around 1600 revs the engine does start to jump n miss alittle after that rev higher or lower it runs perfect... any clue it what might be the cause bad head valve n stuff ?
GTSSportCoupe
2LTE abuser
update regarding the turnscrew... I turned the screw with the engine running clockwise until the engine started to pickup alittle & then tunred it anticlockwise 1/4 turn,that seems to be her sweetspot plenty of power with bucket full of boost n very little black smoke... great result
We put it on the diagnostics and it is showing up that the timing is out... I checked the belt and all it fine right position etc.. BUT at around 1600 revs the engine does start to jump n miss alittle after that rev higher or lower it runs perfect... any clue it what might be the cause bad head valve n stuff ?
Hey Bryan, there are two timing sensors. One in the side of the block and one in the top of the injection pump. I think if there was an issue with either one, you'd be having more problems. These motors do have a missing sound when free revved certain ways I know that. As long as it doesnt miss when you're actually driving it under load. I did have that error code once but it was when I got my timing belt out by one tooth. It was super noticeable with lots of knocking and white smoke from an over advanced pump.
Ahhhhhhhhh I just give up with this 2.4lte donkey of an engine 
So I found this 01 amazon 4.2 fte auto.
Ill start a forum for this transplant later next month. currently pulling the full wiring loom & engine from the donor.
cant wait for the challenge. 
wish me luck.
So I found this 01 amazon 4.2 fte auto.
Ill start a forum for this transplant later next month. currently pulling the full wiring loom & engine from the donor.
cant wait for the challenge. wish me luck.
GTSSportCoupe
2LTE abuser
Ahhhhhhhhh I just give up with this 2.4lte donkey of an engine
So I found this 01 amazon 4.2 fte auto.
Ill start a forum for this transplant later next month. currently pulling the full wiring loom & engine from the donor.
View attachment 1343320
Wicked! I'm looking forward to it!
Job done... (2001) 100 series model amazon 4.2 FTE engine & G'box installed in the (1993) LJ78 series... my 2.4 lte smokey days are well in truly behind me... all went in fine gearbox too ...plus all the metal panel work is original no chopping and taking from the lj78 look.
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wow, didn't know one could squeeze a straight six into a LJ without swapping the front sheet metal for a heavy duty one. Good Job.
GTSSportCoupe
2LTE abuser
That is bar none the coolest swap I've ever seen into an LJ78!! GOOD WORK! Would love more pictures and information of course. That looks like a dream truck right there. 
Still got wiring to finish?
Still got wiring to finish?
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Thanks Lads... its early days yet as I only finished it 4 days ago, but all is going great. the power to weight ratio is what you would expect and more.
I'll put all the photos together & info soon for anyone else to do the transplant...
I'll put all the photos together & info soon for anyone else to do the transplant...
I really wish I hadn't found this post. I foresee this in my future. The 2.4 is the only thing that ever made me hesitate on the Prado purchase. Otherwise, it's my favorite of the Land Cruisers.
Do keep us updated please!
Do keep us updated please!
Hello,
x2.
Amazing job. The 1HD is a big engine. And powerful, too. That 78 must be a rocket now...
Juan
