NOT Firing on all cylinders - Gen 2.5

[nwoods]

My thinking is that if the timing plate was off, then the ECU would be adjusting the ignition timing to run properly without knocking. On reassembly, if the timing plate were in a different position, the ECU would have to make significant adjustments to get the timing back to where it's supposed to be.

Ryan, I don't know what position the timing plate is supposed to be in. It's not addressed in the FSM. It's barely ever mentioned, just once on page 13A-133 and in diagrams on 11A-21 and 11B-16. I assume it oriented with the top of the blade at top dead center, generally in line with the timing mark.

Is that correct?

 

[nwoods]

Those plugs are a real horror show. The two that are completely closed are inexplicable. The #1 broken ceramic could easily have led to a chewed up cylinder, ring damage or even valve seat damage, all or any of which could be contributing to your low compression reading.

If its ring damage, the truck will be towed to the junk yard. If Its head damage.....Jury is still out on that one.

On compression, run a check on ALL your cylinders, as things are. That will give you a baseline of understanding of how the engine is fairing. Find out what your 'normal' range should be. And their shouldn't be but a few PSI variance amongst them all. 5-10psi variance is tolerable and to be expected in a high mileage engine. Specifically on #1, the earlier mentioned oil test - put a good squirt of oil into the cylinder thru the spark plug hole, then immediately hook up the compressor and crank the engine for 5-10secs - will at least determine if your compression problem lays with your rings / bore. Won't diagnose a head gasket or valve trouble. But it would rule out the rings if the compression reading is unchanged.

That was my plan, and part of the reason why I pulled the spark plugs....fortunately, the FSM actually has an excellent step by step procedure for this (11A-11), which shows all spark plugs removed, and the intake manifold removed. I can put the front end back together (if I buy the parts) and run the compression test before I tear apart the heads down to the next level. This is probably what I will do.

As to reading the plugs, any Haynes manual includes a color photo plate / pages, showing all the variances. Yours show an engine that is inhaling a lot of oil. Your intake manifold makes that abundantly clear as well. For a VERY long time. Poor condition of intake manifold gaskets. A frozen or missing PCV valve. Poor ring condition allowing a lot of combustion blow-by which then blasts more oil- and carbon-laden air by the PCV and back into the intake.

Awesome knowledge sharing there! I read your thread with great interest. I would have never thought a cheap PCV valve would cause all that oil fouling through the intake. That does explain what is happening. I was going through a quart of oil every few months, but I just figured 200,000 miles, older car, it was to be expected. But I never really though about the consequences, I just figured it was cylinder wear or rings, or whatever, but it was running so well, no big deal.....or so I thought!

In your photos, what did you use to clean the valve covers and intake ports and so forth?

I also notice the rearmost cylinder on that white / intake gasket in your teardown photo looks terribly mangled at the rearmost corner, did that happen during disassembly, or was it found that way when the intake was lifted off?

Had me panicking there for a minute! I zoomed into the original photo, what you are seeing is just a chunk of plastic sitting on the edge of the intake port. It's one of those comb looking things that separates the spark plug wires. It fell onto the manifold. I removed it seconds after taking the photo. Which reminds me, when cleaning the intake manifold, how to you prevent getting the gunk from falling further in? I can remove the manifold and get down to the block intake, but then I'll have the same problem again, I think. Also, I have no idea how to remove the injectors, and they look fragile.

There's two kinds of sensors in this regard, optical and magnetic. That sensor photo shows a LOT of metal debris clinging to the magnet of the sensor. At this point I would also suggest that you drop the oil pan and 'read the entrails' as it were. You're going to have a terrific amount of sludge to deal with. And are likely to find some debris there. I bit of metal paste, like panning for gold, is also to be expected in high mileage or abused engines. What really matters is the size and appearance of the debris. Bigger shavings or even chunks of metal in there are all terrible signs. BUT NOT UNREPAIRABLE.

Sigh....I just put about $75 of oil into there. I did it two weeks ago when I did the timing belt/ water pump and so forth.

The question then becomes what repairs you are willing to undertake, and what your tolerance is for cost / benefit... I think your biggest trouble is a lack of mechanical knowledge. That's not a criticism, just an observation.

Yes, not being a mechanic makes doing mechanical work infinitely harder. Also, not being mechanically inclined or very dexterous with my fingers raises the challenge level yet further. Unless it comes to cross-threading. I am freakishly good at that. If you need anything cross-threaded, let me know.

I strongly encourage you to fix this motor. You'll learn a lot in the process. You need to, to have a better grasp of the importance of proper preventative maintenance...
eta - I just recently had the bottom end off of one of my motors, some pictures are here, along with a bunch of other stuff on top-end woes -
http://www.expeditionportal.com/for...Vortec-Guys!-Sierra-pickup-Suburban-Yukon-etc
You could learn some things from that topic and maybe some encouragement to keep at it.

The plan is to fix it. It's not like I can make it worse! I just don't quite know what I am fixing. If I only need to replace the crank sensor and spark plugs, it'd be done and and I'd be ecstatic. But that low compression on #1 cylinder is scaring the crap out of me. Time to test them all and see what I'm really in for.

I want to thank you all for your time and contributions to this thread. Collectively, you've been awesomely helpful, and I appreciate all of your continued participation and commentary as I work my way through this.

 

[Salonika]

From where you are at, removing the injectors is easy. Once you unbolt the fuel lines you can just lift up gently on the fuel rail. The injectors are actually just sandwiched in between. I'd stuff some shop towels into the intake holes so nothing falls in there ( you probably should have done that already, btw).
There are seals on both ends of the injectors that you might as well replace while you are at it. Again if you remove manifold you'll need new crush washers when re-installing.

 

[RyanY]

Ryan, I don't know what position the timing plate is supposed to be in. It's not addressed in the FSM. It's barely ever mentioned, just once on page 13A-133 and in diagrams on 11A-21 and 11B-16. I assume it oriented with the top of the blade at top dead center, generally in line with the timing mark.

Is that correct?

It's been far too long since I've had the front of my engine that far apart to remember exactly, but I think the timing plate is notched to be aligned with the crankshaft woodruff key. If that's the case then it just becomes a matter of which side is facing out, since the timing blades are probably not in the same position if it's installed backwards.

 

[IncorpoRatedX]

No, actually, I have no idea where the fuel filter is located. I'm sure it's past due for replacement. I see the diagram on page 13F-8 of the FSM, but that doesn't tell me anything at all, really. Where is it? Is it in the engine bay?

It's underneath the truck. if you follow the fuel line under the truck you'll find a black canister bolted to the frame rail, that's the fuel filter.

I don't know how to test for a vacuum leak. What would I be testing, and where? I didn't hear any sucking air noises while it was running if that's worth anything. What would I use starter fluid for? That sounds like a dumb question, but honestly, no clue? I just put it all back together, turned the key, and it started right back up. It ran fine on idle. I ran it for 20 minutes or so to warm it up when I did the radiator flush. It wasn't until I actually put it in gear and drove it to warm it up faster that I experienced the spark knock. That only happened under load. I could rev it up in the driveway with no problems, but put it in gear and try to accelerate, and it was knock-city. However, that all quickly went away over the next few days.

So with the engine warmed up and running you just spray a TINY bit of starting fluid around gasket areas and hoses, if there's a vac leak the motor will pull starting fluid in through the vac leak and cause the engine to rev up a little, so as you go along spraying around hoses, if the engine RPM suddenly climbs, you know that you've found a leak.

I did not drop them. I used a specialized Craftsman spark plug removal socket with an internal rubber thingie that kept a tenacious hold on the spark plugs. It was moderately hard to pull them out of the socket once removed from the engine!

I was actually hoping you'd say that you did indeed drop them when taking them out. It's basically impossible for those two to create any spark like that.

I drove a couple other Monteros 2 years ago at a SoCal Montero Meet and Greet. My Monty always felt lighter, faster, quicker off the line, and more powerful in general. Mostly due to my skinny 10.5" tires verses their preferences for 12.5" tires. Also, another member here on Expo (DSouth) has driven my Monty, because he kept hearing how slow and gutless they are, and I never had that issue. He drove mine and remarked that it felt powerful to him. Until it died i was able to run 80mph down the freeway and pass any vehicle I needed to without an issue. It was even quick off the line, comparatively. I also occassionaly drive a 450hp Corvette Z06, and a 2015 Porsche 911, so I know what fast is, and the Monty satisfies me plenty.

Wild. I believe what you're saying, im just shocked by it.

I am not mechanical in knowledge, and I can cross-thread a bolt worse than anyone I've ever met, but what I DO have in spades is "mechanical sympathy". I can feel what is going on with a great deal of sensitivity. I've raced cars and done a lot of rock crawling, and always and everywhere my one general edge was that I am able to feel what the vehicle is doing with a high degree of precision. I am very sensitive to everything going in the vehicle. I am kinda OCD about it. I insist on having a rattle free interior cabin. When I pack tools, it is a meticulous ordeal to wrap every tool, strap down every movable item, clean and clear the glove box and cubby's of anything loose, etc.. When rock crawling, I can account for, and feel, every lug on the tire as I climb over an obstacle. When racing, I am totally in sync with the tranny and engine revs and the limit of grip, I know when the rear tires are hot and the front tires are loose, I know when the brakes are fading, and when the oil is cooking. I totally get dialed in. I'm that guy that hears everything, feels everything, and drives any car salesman or service writer crazy. I may not know why its doing what its doing, but I can tell when its doing it.

It's important to know where your strengths and weakness are so kudos on that. turning wrenches isnt for everyone. those of us that enjoy it seem to think it's a fun hobby to have, those who dont take to it easily seem like fish on land, high stress and high stakes.

Interesting.... I was talking to SneakyNinja about buying your current 99 project, and asked about trading my hulk plus cash. He said you guys were too backed up on personal projects to start another investment truck.

Yeah I'd have to buy it as a parts rig on my own and it would probably get stripped for the parts i need and hauled off for scrap pretty quick, the mighty max doesnt get a 4x4 drivetrain until next year, he's absolutely right though, we have too many trucks (and cars) to rescue as it is.

 

[IncorpoRatedX]

Awesome knowledge sharing there! I read your thread with great interest. I would have never thought a cheap PCV valve would cause all that oil fouling through the intake. That does explain what is happening. I was going through a quart of oil every few months, but I just figured 200,000 miles, older car, it was to be expected. But I never really though about the consequences, I just figured it was cylinder wear or rings, or whatever, but it was running so well, no big deal.....or so I thought!

Ive been seeing this on all the mitsu engines. I've heard about it on jeeps and old beemers before but on the mitsu engines I've experienced it.

I'll tell you a little story, maybe it will lighten your day a little.

I bought a stock Galant VR4 with excitement, no mods, ran perfect, AC even worked, I was in heaven. After driving it for a few weeks and deciding what it needed it got a budget together and bought a bunch of parts. Did a lot of nice stuff to the cars brakes and suspension, then one day, being the knob that I am, I'm waiting for my iced latte to come up at the drive through and I notice a small ploom of smoke wafting from the back of my car. I've been knee deep in mitsu engines for 20 years, so I suspected valve stem seals, stabbed the skinny pedal and more smoke shot out of the exhaust and drifted toward the front of the car...
"I love the smell of burning oil in the morning!" i exclaimed as I grabbed my latte and drove off with excitement.

To most people that's a sign of work to be done. To me (and others like me) it was an excuse to replace the timing belt, water pump, tensioners, throw some ARP head studs in the motor along with a nice fresh head gasket, new seals, some Crower 264 cams, new stem seals, a full clean, oh!, maybe upgrade the turbo and exhaust manifold while im in there... oh yes, to a guy like me, a reason to dig into something I want to mod is like, well, it's an addition, you get the picture. I sat at my desk that day dreaming about the inside of the untouched engine. it was a one-owner car, with full service history, I was excited and thought 'i better pick up more oil since it's burning oil at idle now'. Of course I ran full synthetic VR1 oil in the VR4, it's $10 a bottle, so until all the parts arrived I was putting a bottle of oil in the engine every sunday before my work week. I think that went on for about 5 weeks while i searched for the second crower cam i needed (already had one), so about $50 in oil.

I'm telling you this because I overlooked all my knowledge, I was excited to get some cams in that head and juice up my ride a little. After i dropped $1500 on some fun go-fast and 'bullet proof' parts, I ended up completely rebuilding the top end of the engine and all it actually needed was a $5 PCV valve. It was stuck and was filling the intake with oil and then burning the oil and pumping it out of the exhaust. It looks just like when the stem seals go bad, except the intake gets coated with oil, mine was covered in an 1/8th inch thick varnish of baked on oil. Needless to say after replacing the parts it ran great and never smoked, I went balls deep over a $5 part...

to remove the oil build up, get a gallon jug of purple power and a moving/storage tote, fill the tote with hot water and put in a quart of the purple power, let the manifold soak overnight and then hit it with a hose the next day, most of the build up will come off. anything that doesnt might need a toothbrush to agitate it or it might need to soak in the hot water/cleaner solution again.

 

[normal_dave]

Since we're confessing, "me too", although I didn't plan on upgrading cams...

What I did do was buy a generic PCV valve for my 3.5L '03 Sport, which rattled ok, but didn't work. Finally sprung for the OEM one and that did the trick. Our Monteros use a different style so they may not be as picky.

 

[nwoods]

There are seals on both ends of the injectors that you might as well replace while you are at it. Again if you remove manifold you'll need new crush washers when re-installing.

Trying to figure out which seals and gaskets you are referring too. RockAuto has a variety listed, no idea what I need:

or

or

or the bottom two of this one:

 

[IncorpoRatedX]

Trying to figure out which seals and gaskets you are referring too. RockAuto has a variety listed, no idea what I need:

That's what you need for the injectors, that picture will complete one injector seal set. What you have there is:
-Top left:goes on top of injector, works as a bushing between the fuel rail and the injector, this prevents the injector from getting smashed into the fuel rail too far, this is the least important of the three
-Top Right: This goes on the bottom of the injector, then inserts into the intake manifold, this is what seals the injector to the intake manifold, a leak here would be a significant vacuum leak and can cause a lean condition in a cylinder that will burn a valve
-Bottom Middle: O-ring for the top of the injector, goes onto the injector and then slips inside the fuel rail, this seals your fuel in the system, be sure to add a little oil or lubricant to them when you install the injector back into the fuel rail, proper care should be taken not to cut the o-ring while working the injector back into the fuel rail, being too forceful can shred or tear the o-ring, at 40-60psi, you dont need fuel blasting onto the top of your engine.

 

[nwoods]

Awesome. Thanks for the info, and about the cleaning solution.

 

[rayra]

nwoods, on my oil-fouled intake portion of the heads, I stuffed a wadded paper towel down in the bottom of each one to block off the valve end of the passage, then used non-chlorinated brake cleaner and rags and paper towels. I first liberally soaked another / new paper towel, rubbed the bulk of the sludge off, then used a saturated shop rag to go after the rest.

I then hit each intake port with a shop vac to hopefully get any loose chunks and fished out the wadded towel with the vac still going. My greatest concern was getting a chunk of junk down where it would get mashed in the valve seat and foul things up semi-permanently.

On my intake, off the vehicle, I used a variety of spray chems after I stripped off the sensors. Since sensor-safe spray cleaner is expensive stuff. I used some gas-soaked rags on a long spring / claw tool to clean out the intake runners, much like cleaning a rifle barrel.



Don't get overwhelmed by the whole thing. It's just a puzzle of parts. I take a lot of pictures and notes and put numbered bits of masking tape on a lot of things, if I'm doing something new to me. Just be careful to not break brittle old plastic and vac lines, and don't strip or break old nuts and bolts. Get some penetrating oil for the frozen stuff and give it time to work while you do something else.
Most of mechanical work, any trade really, is learning a grab bag of useful tips and tricks. The rest - and I mean engines, sprinklers, tile setting, electrical, all of it - is just puzzle solving. Figuring how pieces go together in the proper way. Or come apart. And the various specialty tools to each trade. Don't be daunted or frustrated by it. Just start small and simple and build from there.


One of the things to learn right off is what's important and what's not. A few leaks or grunge is not important. It isn't right, but it's relative. Your goal is accurately identifying and diagnosing your troubles so you can then get a reasonable estimate of your costs of (minimal) repair. Then look at it and see what other targets of opportunity you should best address while you are working on a particular subsystem. If you can afford the cost. I mean if you've removed 90% of the stuff to put a new timing chain set on, it would be a good time to do it. maybe a bad example, there's other concerns with that.

As to having just put $75 worth of oil in it, dont' tell anyone I said this, but who says you have to throw it out. Given the grunge condition of that engine it scarcely matters if you re-use it. Just take care to clean the pan before you drain it, let it settle, then carefully pour it off into some empty / dry gallon water jugs while you do the rest of the engine work / pull the pan. Just don't forget to put it back in before you try and run it again. Or crank it much.

If you are lucky, it's just a bad intake gasket and PCV. But I honestly doubt it. That much crud is the product of a lot of miles without proper oil changes and at either high revs or worn rings. That's a LOT of carbonized junk in that motor. in fact, I'd strongly suggest putting some cheap oil in it when you put it back together and once you know it is running ok, put a quart of flush in it and get out as much of that crap as you can. Drain it all then put your expensive oil back in.