First car, lx450!

[BILT4ME]

Did some mild cleaning (more in depth this week) and I think I found the main leak I'm seeing (definitely not heater control valve, though it's leaking for sure). It seems like a bunch of oil is collecting on the 6th cylinder of the head on the exhaust side. It's kind of hard to see from the pictures, but seems like that's where it's originating. It then leaks down to the top of the exhaust manifold, and ends up dripping under the car. Seems like it's leaking from the valve cover gasket kind of all over, but mostly 6th cylinder area.

Two questions: this seems like most probably cause here would be a valve cover gasket (doubt it's been replaced in 170k mile lifetime)? also, if it is leaking directly onto the exhaust manifold, is it worth it to replace exhaust manifold gasket? just seems like pulling it can be kind of rough getting the bolts out, mine isn't in great shape.

View attachment 3651464View attachment 3651465

Fix it until it's broken.



Valve cover gasket
Spark plug tube seals
PCV grommet
Throttle body gasket
Distributor o-ring
Oil pump seal
Front main seal
Power steering hoses (high pressure and low pressure)

The above list will fix 95% of your oil leaks.
Change all hoses (vacuum and coolant) while you're in there.

 

[tug123]

Fix it until it's broken.



Valve cover gasket
Spark plug tube seals
PCV grommet
Throttle body gasket
Distributor o-ring
Oil pump seal
Front main seal
Power steering hoses (high pressure and low pressure)

The above list will fix 95% of your oil leaks.
Change all hoses (vacuum and coolant) while you're in there.

As always, thank you this is perfect. While I'm in there might as well change belts too, looking a little iffy. Will stop at dizzy o-ring for now (w/ cap+rotor), do all the other stuff, and then come back to the more complex stuff.

 

[ZackR]

Did some mild cleaning (more in depth this week) and I think I found the main leak I'm seeing (definitely not heater control valve, though it's leaking for sure). It seems like a bunch of oil is collecting on the 6th cylinder of the head on the exhaust side. It's kind of hard to see from the pictures, but seems like that's where it's originating. It then leaks down to the top of the exhaust manifold, and ends up dripping under the car. Seems like it's leaking from the valve cover gasket kind of all over, but mostly 6th cylinder area.

Two questions: this seems like most probably cause here would be a valve cover gasket (doubt it's been replaced in 170k mile lifetime)? also, if it is leaking directly onto the exhaust manifold, is it worth it to replace exhaust manifold gasket? just seems like pulling it can be kind of rough getting the bolts out, mine isn't in great shape.

View attachment 3651464View attachment 3651465

That leak is from the valve cover gasket. It won't hurt the exhaust manifold gasket so no need to worry about it.

For the heater valve hoses and clamps you can also just cut sections of straight hose and use normal hose clamps. For the PHH I personally removed the hard pipe and used a longer hose all the way around, the purists won't like it but I still sleep just fine.

 

[tug123]

That leak is from the valve cover gasket. It won't hurt the exhaust manifold gasket so no need to worry about it.

For the heater valve hoses and clamps you can also just cut sections of straight hose and use normal hose clamps. For the PHH I personally removed the hard pipe and used a longer hose all the way around, the purists won't like it but I still sleep just fine.

Definitely what it seemed like, other stuff like dizzy o-ring still are probs worth it to do. PHH yeah I was just looking at someone who did that, so many opinions though I just decided to grab the full pipe assembly and call it a day.

Should pull intake manifold this week, just trying to gameplan it on those 5th/6th cylinder bolts. Seems impossible without pulling the starter.

 

[ZackR]

Definitely what it seemed like, other stuff like dizzy o-ring still are probs worth it to do. PHH yeah I was just looking at someone who did that, so many opinions though I just decided to grab the full pipe assembly and call it a day.

Should pull intake manifold this week, just trying to gameplan it on those 5th/6th cylinder bolts. Seems impossible without pulling the starter.

I used some long socket extensions and a bright light, no need to pull the starter. Some are bolts and some are nuts.

Wear safety glasses to keep stuff out of your eyes.

 

[tug123]

I used some long socket extensions and a bright light, no need to pull the starter. Some are bolts and some are nuts.

Wear safety glasses to keep stuff out of your eyes.

Sounds like a plan, I'll go into it with lots and lots of hope haha. Learned the need for glasses the hard way, it's a good reminder.

 

[tug123]

Pulled throttle body (fuel injectors looking grim, hopefully just the dust). Will pull intake manifold tomorrow, doesn't seem like it will take too long. Only issue is that EGR pipe nut, impossible to get without ruining the EGR wiring harness. Seems like I could just leave the EGR valve on the pipe nut and pull the intake manifold as is, is that bad if I'm just careful not to bump it?

 

[ZackR]

You can leave the EGR in place. Unbolt it from the upper intake and you'll be good.

 

[tug123]

You can leave the EGR in place. Unbolt it from the upper intake and you'll be good.
View attachment 3652313

Dang everything looks so nice haha I should probably consider replacing a bunch of my sketchy bolts too. Thanks though I figured just wanted to check!

 

[tug123]

Definitely pushed my amateur mechanic skills to the limit, but intake manifold and fuel rail are out. I was hoping the PHH would be in a really nice, accessible spot but nope zero idea how I'll replace that (or half the hoses I planned on replacing). Fuel kept coming out until I unscrewed the gas cap, think the pressure from the faulty charcoal canister. In pictures below, injector #1 is on top and #6 is bottom.

Injector #6 connector would not come out, had to cut it (thanks to @CharlieS for mentioning the injector connectors, wouldn't have felt comfortable cutting otherwise). Even with the injector out of the fuel rail, I still cannot get it to come off. Gonna take a wild guess and say that is the cause of the cylinder #6 misfire. All injectors (even #6) were within 13.7 - 14.1 ohms so within spec.

Couple of questions:

• what do I do with this sixth injector now? any tricks to getting the connector loose? ideally I just send em all off to RC and not have to buy new ones.
• are there specific plugs I can use to plug up the injector holes in the engine block? I'd like to clean all around since it's pretty grim.
• worth cleaning the fuel rail?

 

[ZackR]

Couple of questions:

• what do I do with this sixth injector now? any tricks to getting the connector loose? ideally I just send em all off to RC and not have to buy new ones.
• are there specific plugs I can use to plug up the injector holes in the engine block? I'd like to clean all around since it's pretty grim.
• worth cleaning the fuel rail?

I'd spray the connector with penetrating oil and let it soak for a while, then try again to remove the connector.

I'm sure there are specific plugs but you can also just put an injector back into place and clean the area around it. Once its clean put a clean rag in there, same with the lower intake.

Might as well clean the fuel rail and whatever else you can access while its opened up. I personally use rubbing alcohol and a old toothbrush.
As for the PHH the hardest part is the bolt that holds the hard pipe in place. Some people just bend it enough to break free, others can get in there an undo it with a wrench. Once mine was out I decided not to put it back in. Cut the PHH with a utility knife.

Nice work so far, take photos as you go and it'll be easy to put it all back together. Also an easy way to keep track of nuts and bolts is with a cardboard box with the bolts shoved into holes and labeled.

 

[tug123]

I'd spray the connector with penetrating oil and let it soak for a while, then try again to remove the connector.

I'm sure there are specific plugs but you can also just put an injector back into place and clean the area around it. Once its clean put a clean rag in there, same with the lower intake.

Might as well clean the fuel rail and whatever else you can access while its opened up. I personally use rubbing alcohol and a old toothbrush.
As for the PHH the hardest part is the bolt that holds the hard pipe in place. Some people just bend it enough to break free, others can get in there an undo it with a wrench. Once mine was out I decided not to put it back in. Cut the PHH with a utility knife.

Nice work so far, take photos as you go and it'll be easy to put it all back together. Also an easy way to keep track of nuts and bolts is with a cardboard box with the bolts shoved into holes and labeled.

View attachment 3652803

Full of good ideas, as always thank you! Answers all my questions, great idea with the fuel injectors. I'll try to get it out, clean everything and ship em off to RC.

Makes sense on PHH, if it's too much of a nightmare I'll just leave it out. Cardboard box is a great idea I've been labeling with electrical tape but its crazy time consuming.

One other thing - notice the extra big heatshrink (no idea what it's called) on your wire harness is replaced. Mine is really really brittle, sometimes will crumble just from the touch. Does that mean I probably ought to pull the wire harness and fix it all up? Part by the EGR is even more crumbly.

 

[ZackR]

My photo shows a brand new wiring harness so its definitely not apples to apples to what you are seeing. If you are really planning on keeping the rig for the long haul and you have the money I'd recommend buying a new OEM replacement wiring harness (they still make them for 95+), even if you don't install it now. Mine is a 94 and the harness was discontinued in 2015 so it took me 1.5 years and a lot of money to find a new one.

At this point you don't need to pull the whole harness out, rather just cut open the crispy area and inspect/repair the wires inside (keep opening it up further if needed to fix all the damage). Once that's complete tape it up and cover with a layer of wiring loom (zip tie the loom in place) to protect the harness. Here's the key thing - secure it away from the EGR pipe to prevent future heat damage.

 

[tug123]

My photo shows a brand new wiring harness so its definitely not apples to apples to what you are seeing. If you are really planning on keeping the rig for the long haul and you have the money I'd recommend buying a new OEM replacement wiring harness (they still make them for 95+), even if you don't install it now. Mine is a 94 and the harness was discontinued in 2015 so it took me 1.5 years and a lot of money to find a new one.

At this point you don't need to pull the whole harness out, rather just cut open the crispy area and inspect/repair the wires inside (keep opening it up further if needed to fix all the damage). Once that's complete tape it up and cover with a layer of wiring loom (zip tie the loom in place) to protect the harness. Here's the key thing - secure it away from the EGR pipe to prevent future heat damage.

Ah that makes sense. Yeah buying one just to have is not a bad idea, the longer I do this the more it seems like buying certain things to have on hand is not a bad thing at all.

Makes sense as well on the wiring loom (that's what it's called!). For damaged wires, seems like best advice I've seen is crimp + heatshrink, soldering over the bay seems sketchy at best (and very short term).

Only other thing that's bugging me is it's not 100% clear what was causing the #6 misfire. Compression is great, fuel injectors are all within spec for resistance (could be clogged I guess), wiring seems kind of okay (got the connector out finally). But I guess a misfire can't really be caused by many things, it's gonna be compression, injectors, or wiring right? Or is there something else here I ought to check while it's all open. Worst thing would be if I put it all back together and it's still misfiring.

 

[ZackR]

If you find a wire with missing insulation and its still intact (meaning the copper looks good) inside the harness I'd just tape it carefully. Use good tape (3M Super 88). If the wire is bad then cut, crimp, pull test and heatshrink but don't soldier it.

Report back with some photos on what you find inside the wiring harness.

 

[effjay80]

Nice work.

 

[tug123]

If you find a wire with missing insulation and its still intact (meaning the copper looks good) inside the harness I'd just tape it carefully. Use good tape (3M Super 88). If the wire is bad then cut, crimp, pull test and heatshrink but don't soldier it.

Report back with some photos on what you find inside the wiring harness.

Sounds good, makes sense thank you! Will circle back after

 

[60 toy ota]

If the wire is bad then cut, crimp, pull test and heatshrink but don't soldier it.

I know there's lots of debate on this and both soldering and crimping can be done very poorly or very well, but I want to just make a small hijak to elaborate on this so the OP (and anyone else) steps into this repair with a little better preparation.
In theory, I agree that the best possible connection would be a crimp exactly the way that the factory does it when they make an internal splice (their published wire repair instructions for their dealership mechanics also call for crimping). In practice, however, the best connection a hobby mechanic will make in their home garage will depend heavily on their knowledge/skill/equipment on hand.
too many people hear that crimping is better and they rummage through their electrical drawer and find the best fitting butt connector in their autozone kit and pinch it with the matching color on their strippers (unless they are bent or misplaced or out of reach, in which case pliers will do just fine), and wonder why they have electrical gremlins 6 months later. It takes a little initial investment, but if you think wire repair on critical systems is something you are willing to tackle you can get a good entry level, adjustable force ratcheting crimp tool with interchangeable dies like this as well as a kit of seamless barrel crimps like these for ~100 or less. now you are set up not only to make high quality butt splices but you can have a specific crimp die for just about anything from lugs and ferule terminations to OEM connector pins, in addition to the solid barrel crimps used in this repair.

On the other hand, people shy away from buying the proper crimping tools or need to get the job done with whatever they have on hand so they turn to soldering. Honestly, I think a good solder would work just fine even next to the EGR and I certainly would go that route before using a cheap low quality crimp. Other than the true rookie mistake of cold joints (heating the solder directly till it is able to drip onto the strands, as opposed to heating the wire and letting the WIRE melt the solder), The biggest concern with soldering is making the wires brittle wherever the solder hardens. what many don't realize is that the the heated wires suck the solder up the strands in capillary action, making the brittle section of wire much longer than just the splice area, like several inches on each side. They just see that the joint doesn't seem "saturated" with solder and they keep feeding it more saying "if some is good more is better", all the while turning flexible stranded wire into effectively solid core wire. You can see how that would quickly become an issue in a harness that is designed to flex with engine torque and handle driveline vibrations. prolonged heating of the wires can also easily damage wire insulation. I would not recommend building your skill in a difficult to access and highly critical area like this, but that said if you have the skill already it can be done with great reliability and I personally have had great success with soldered joints in automotive applications.



Anyway, you have a good game plan for finding your misfire and I'm confident you'll get it sorted out. You'll find even more satisfaction every time you turn the key and the thing just purrs!

 

[60 toy ota]

Final result:

 

[tug123]

Checked both EGR wire harness and the glove box wire harness, honestly both seem pretty okay - can't really find a single spot of an exposed or melted wire. Pictures added below.

No worries on hijacking haha, this is very helpful to me, especially as I'm looking at my wires right now. My soldering skills are far from professional level, but good crimper is definitely needed. Only annoying part about crimping is how much space it can take up, there's gotta be at least 50 wires in here.

I know there's lots of debate on this and both soldering and crimping can be done very poorly or very well, but I want to just make a small hijak to elaborate on this so the OP (and anyone else) steps into this repair with a little better preparation.
In theory, I agree that the best possible connection would be a crimp exactly the way that the factory does it when they make an internal splice (their published wire repair instructions for their dealership mechanics also call for crimping). In practice, however, the best connection a hobby mechanic will make in their home garage will depend heavily on their knowledge/skill/equipment on hand.
too many people hear that crimping is better and they rummage through their electrical drawer and find the best fitting butt connector in their autozone kit and pinch it with the matching color on their strippers (unless they are bent or misplaced or out of reach, in which case pliers will do just fine), and wonder why they have electrical gremlins 6 months later. It takes a little initial investment, but if you think wire repair on critical systems is something you are willing to tackle you can get a good entry level, adjustable force ratcheting crimp tool with interchangeable dies like this as well as a kit of seamless barrel crimps like these for ~100 or less. now you are set up not only to make high quality butt splices but you can have a specific crimp die for just about anything from lugs and ferule terminations to OEM connector pins, in addition to the solid barrel crimps used in this repair.

On the other hand, people shy away from buying the proper crimping tools or need to get the job done with whatever they have on hand so they turn to soldering. Honestly, I think a good solder would work just fine even next to the EGR and I certainly would go that route before using a cheap low quality crimp. Other than the true rookie mistake of cold joints (heating the solder directly till it is able to drip onto the strands, as opposed to heating the wire and letting the WIRE melt the solder), The biggest concern with soldering is making the wires brittle wherever the solder hardens. what many don't realize is that the the heated wires suck the solder up the strands in capillary action, making the brittle section of wire much longer than just the splice area, like several inches on each side. They just see that the joint doesn't seem "saturated" with solder and they keep feeding it more saying "if some is good more is better", all the while turning flexible stranded wire into effectively solid core wire. You can see how that would quickly become an issue in a harness that is designed to flex with engine torque and handle driveline vibrations. prolonged heating of the wires can also easily damage wire insulation. I would not recommend building your skill in a difficult to access and highly critical area like this, but that said if you have the skill already it can be done with great reliability and I personally have had great success with soldered joints in automotive applications.



Anyway, you have a good game plan for finding your misfire and I'm confident you'll get it sorted out. You'll find even more satisfaction every time you turn the key and