NOT Firing on all cylinders - Gen 2.5

[BOPOH]

im surprised your engine ran at all with everything that you posted above. My personal opinion about low compression is that if engine is cold it will be nowhere near close unless you put some oil through spark plug hole and test it this way. The reason i say that is when i tested other engines i would have 150psi on warm and barely getting 70psi on cooler engine, i mean 10-15 minutes after i was reading 150psi. Don't worry too much about broken porcelain either, at one point somehow my engine suck a good size rock through intake. I got some internal damage such as bashed piston and dented cylinder head, walls however were perfect. Rock turned into dust and got out.

Long story short, fix everything you know are bad and start it up. while you are there dont forget to check cam sensor

 

[IncorpoRatedX]

I'm taken back by this.

How old are those plugs?

I can't believe the truck even ran.

Looks like it was running on cylinders 2, 3, and, 5... yikes. Was the timing ever off? By just a tooth maybe? A lot of that looks like advanced timing /or/ running low octane fuel with advanced timing, looks like the start of burnt valves, which could be what lends to the low compression, could be worse and plug porcelain damaged the cylinder wall or the piston ring. tough to say, but by the looks of those plugs, it's not good.

You might be reaching the point of throwing in the towel man.

 

[nwoods]

im surprised your engine ran at all with everything that you posted above. .... while you are there dont forget to check cam sensor

Thanks for that. I was wondering about it, if people replace them in pairs or not. It's another $35 for a replacement cam sensor.

 

[nwoods]

How old are those plugs?

Not sure. I never did the plugs, so they are at least 2 years old. I bought the truck with right around 190,000 miles on it. It has 210,000 miles now. They aren't OEM plugs, so at least they aren't 210,000 miles old

Was the timing ever off? By just a tooth maybe?

I don't know how i'd know (I'm not even remotely mechanically inclined), but I don't think so? When we pulled the old belt off, it the timing marks all lined up, and as you can see in the earlier photos, they are still aligned after running for the week and a half or so between doing the timing belt and the truck developing the engine miss. Recall that the timing sensor plate was loose (behind the crank gear) when we first did the tear down. And that when we put it all back together, there was very heavy spark knock for the first few days until the ECU recalibrated. I typically run low octane (87) fuel, because it's cheap older truck with a low compression (9:1) engine that shouldn't need high octane fuel. The spark knock went away after a few days of driving, so I figured it was a calibration thing. Could have just been the spark plugs giving up the ghost

I can't believe the truck even ran.

I know! And it ran really, really well... until it didn't. Lots of power, decent fuel economy. I've had ongoing electrical issues forever though, and always have had a CEL on for one reason or another, but it ran great. Could all this have happened around the time the water pump gave out?

You might be reaching the point of throwing in the towel man.

That's the $300 question. Is it worth me putting another $300 in parts into this thing, only to pay to have it towed away? I don't know how to make that decision. I don't have enough experience or technical knowledge to make an informed decision.

I could install new sensors, crank gear, timing plate, gaskets, plugs and wires, put it all back together, and have nothing positive happen. Makes spending another $150 on a OEM timing belt tensioner a rather dubious investment.

 

[BOPOH]

what parts do you have and what are you planning on getting?

 

[normal_dave]

It is a tough call sometimes. I usually try to salvage what I already have, (better the evil you know?)

How's the rest of the truck? Body, interior, transmission? Is this the first time since you bought it you've really had to put a chunk of money and time into it? I encountered quite a run of maintenance on our 3.5L Sport, but the outcome was so good, I ended up being irritated at myself for not doing it all sooner.

First I had a chocolate milkshake form in the coolant overflow bottle, I thought man, the head gasket is gone. Further research revealed a slow leak in the coolant crossover pipe/rear heater connection behind the engine caused the foaming along with coolant that had gotten too old. That cleanup and repair was well worth it.

Later the valve seals started to go, causing "old smoky" at extended idle, and lots of oil usage, that never seemed to generate a leak on the garage floor. Turned out to have a combination of valve seals, PCV valve failing, clogged pcv passages, a handful of bad lifters (cracked plastic rings and/or wouldn't hold pressure), and to top it all off, after replacing a couple O2 sensors after reading codes, discovered a fairly common issue on our 3.5L. the EGR system solenoid valve failed, causing the CEL, but coding O2 sensors. This made sense after I fixed the solenoid with an OEM unit. This solenoid btw, is located on a bracket near the back of the block, to the passenger side of the coolant bypass pipe.

Related to your issues, my bad lifters caused excess detonation when lugging up a hill in drive, caused poor throttle response, were noisy at startup, and a few almost always ticking away at idle. The pcv valve and passage clogged added to the oil use problems, gummed up the intake runners, and I'm sure didn't help matters.

At the end of the day, my oil usage problems are gone, the thing runs so well, and has such great throttle response, we've had to ease up on the pedal. It was quite a job to do all that work, but now that it is behind me, I have great confidence it will continue to meet our needs. My wife won't have any other vehicle, I even ended up ordering a complete Katzkin leather interior to replace the original leather ('03 Sport Limited). All this beats a car payment of course, and with a replacement vehicle, I'd be taking chances all over again on maintenance.

You've jumped in with both feet, and seem to be fearless in the maintenance department, I think with good technical support, you should be able to handle the rest. Read DJPurdue, he has pulled his heads to fix a compression issue with little to no prior experience on this engine, and seems to be making out ok.

On the other hand, since I'm a recent Gen 3 convert, You could choose one carefully, make the jump and never look back.

Here's an example of what I think is a potential diamond in the rough...going to post in in the craigslist section as well.
2001 Montero Limited, $ 1,500 negotiable, Eugene, Oregon. Body looks good, check out the interior shots, if the ad story is at all true, I would bet the prior owner had a decent maintenance history, and garage kept.
https://eugene.craigslist.org/cto/5651817639.html
Sounds like the brake booster motor is failing, the cheap fix here:
https://www2.pajeroclub.com.au/forum/showthread.php?t=46516

Getting the thread back on topic, If you are going to do spark plugs, etc. Let's consider knocking out the lifters, while in the neighborhood. Do you recall smoking at idle, or lots of oil consumption? then valve seals.
I know I'm beating a dead horse with this one, but it was a night/day difference on my truck, and wasn't a bad job, (lifters)
http://www.club3g.com/forum/maintenance/165458-how-bleeding-lifters-v6.html

Good Luck either way.

 

[IncorpoRatedX]

Not sure. I never did the plugs, so they are at least 2 years old. I bought the truck with right around 190,000 miles on it. It has 210,000 miles now. They aren't OEM plugs, so at least they aren't 210,000 miles old

I don't know how i'd know (I'm not even remotely mechanically inclined), but I don't think so? When we pulled the old belt off, it the timing marks all lined up, and as you can see in the earlier photos, they are still aligned after running for the week and a half or so between doing the timing belt and the truck developing the engine miss. Recall that the timing sensor plate was loose (behind the crank gear) when we first did the tear down. And that when we put it all back together, there was very heavy spark knock for the first few days until the ECU recalibrated. I typically run low octane (87) fuel, because it's cheap older truck with a low compression (9:1) engine that shouldn't need high octane fuel. The spark knock went away after a few days of driving, so I figured it was a calibration thing. Could have just been the spark plugs giving up the ghost


I know! And it ran really, really well... until it didn't. Lots of power, decent fuel economy. I've had ongoing electrical issues forever though, and always have had a CEL on for one reason or another, but it ran great. Could all this have happened around the time the water pump gave out?


That's the $300 question. Is it worth me putting another $300 in parts into this thing, only to pay to have it towed away? I don't know how to make that decision. I don't have enough experience or technical knowledge to make an informed decision.

I could install new sensors, crank gear, timing plate, gaskets, plugs and wires, put it all back together, and have nothing positive happen. Makes spending another $150 on a OEM timing belt tensioner a rather dubious investment.

They look old and more importantly, majorly deposited and quite worn down. Electrode wear, some wear - is normal, excessive wear; generally means too hot and too lean, which is often related to a vaccum leak, timing or fuel delivery issues. Do you keep up on your fuel filter? You mentioned it ran rough at first with spark knock, did you test the truck for vacuum leaks after you put it back together with starting fluid or anything?

I'm finding it hard to believe that it ran well at all man. I've driven in a montero when it lost a coil and thus lost two cylinders of spark and that motor fell flat on it's face. two ungapped plugs cant spark so it's like dropping a coil and running on 4 cylinders, did you maybe drop them while removing them?

Have you driven other monteros? I wonder what your perception of a good running one is, no offense intended, but if the truck has always been a little down on power you might be shocked to find how a good running one behaves. If you decide to throw in the towel, let me know. drivetrain parts from that truck would be great under my girlfriend's mighty max if you decided to scrap it/sell for parts.

 

[nwoods]

They look old and more importantly, majorly deposited and quite worn down. Electrode wear, some wear - is normal, excessive wear; generally means too hot and too lean, which is often related to a vaccum leak, timing or fuel delivery issues. Do you keep up on your fuel filter?

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?

You mentioned it ran rough at first with spark knock, did you test the truck for vacuum leaks after you put it back together with starting fluid or anything?

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.

I'm finding it hard to believe that it ran well at all man. I've driven in a montero when it lost a coil and thus lost two cylinders of spark and that motor fell flat on it's face. two ungapped plugs cant spark so it's like dropping a coil and running on 4 cylinders, did you maybe drop them while removing them?

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!

Have you driven other monteros? I wonder what your perception of a good running one is, no offense intended, but if the truck has always been a little down on power you might be shocked to find how a good running one behaves.

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.

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.

If you decide to throw in the towel, let me know. drivetrain parts from that truck would be great under my girlfriend's mighty max if you decided to scrap it/sell for parts.

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.

 

[nwoods]

what parts do you have and what are you planning on getting?

Don't have any parts yet. What I'll need, for starters, includes:

Crank sensor
Cam sensor
Crank gear (because i buried that damn pin)
Timing plate
Valve gaskets
EGR gasket
Intake manifold gasket
Spark Plugs
Spark plug wires
OEM timing belt tensioner (maybe)
Compression tester assembly/tool
Left bank exhaust header (maybe - mine is cracked, but that looks like a real PIA of a job)

If go in any further, I'll need head gaskets and other things I'm sure.

 

[nwoods]

How's the rest of the truck? Body, interior, transmission? Is this the first time since you bought it you've really had to put a chunk of money and time into it?

The body doesn't have a straight piece of sheet metal on it. I love it. It's perfect for the trails and my teenage son.
However, the interior used to look like it was used to haul bulk oil, used oil that is, in open containers. Stains everywhere. Carpet was horrendous. Interior is so dusty from the desert that when you close the doors hard, clouds of dust swirl about, sort like beating a throw rug to clean it. But it actually cleans up okay, with a lot of hard work. I threw out the carpet and replaced it as soon as I got the truck. I'm pretty critical about interiors. I bought this rig from Eurosonic who described the interior as an 8 on a scale of 10. I assumed 10 was high, but upon delivery (i bought it sight unseen), I have come to realize that our crazy Russian friend has an entirely different scale for acceptable interior conditions. Upon delivery, I would give it a 3, after a 10 hour deep cleaning and detailing. Currently, maybe a 7 after detailing.

Yes, unfortunately, I've put a lot of money into this thing. Not being mechanically inclined, I paid to have the driver side exhaust manifold replaced. I paid to have the timing belt job done. I paid to replace the windshield. I paid to replace the passenger mirror. I paid to drain and flush the tranny, transfer case, and front and rear diffs. I've replaced the shocks and brakes and tires (myself). I've replaced the battery and alternator (FIVE alternators now). I added a stereo, replaced all the speakers, installed an amp and a sub. I easily have my original purchase price back into her in maintenance and upgrade costs.

Fortunately, it's been fairly solid in all ways except electrically. It has always been an eater of alternators and voltage regulators, and periodically exhibits all sorts of weird electrically related behaviors and faults, but nothing that would keep it off the road or trail. Its been a dedicated trail rig for me, and a daily driver for my teenage son for the past 2.5 years, and we've gotten our moneys worth out of it for sure.

And, i still trust it. If I can get it running again, I wouldn't hesitate to take it out on a week long camping trip through the Mojave.

 

[normal_dave]

Alternators- grrr.

Have you checked your passenger front cam seal? They are notorious for leaking, dripping right onto the alternator and eventually shorting the electrics. I ate two alternators before I learned what was happening. Check the bottom of the alternator for oil...

 

[nwoods]

Alternators- grrr.

Have you checked your passenger front cam seal? They are notorious for leaking, dripping right onto the alternator and eventually shorting the electrics. I ate two alternators before I learned what was happening. Check the bottom of the alternator for oil...

Yes my first two alternators went out that way. But then the leak stopped happening. Not sure why, but the last three alternators have been bone dry.

 

[RyanY]

I'm thinking that your detonation issues after reassembly were due to the crank sensor timing plate not being indexed or installed correctly - not sure whether it was before hand or afterwards. 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. I've done several timing belt services myself and haven't had any of the spark knock issues that you've described.

 

[rayra]

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.
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.

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.

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?


If as you say the engine was 'running great until it wasn't', then it would certainly be worth the few hundred $ to correct all the known faults you have right now. I would also suggest you look closely at the condition of the electrical connectors and wiring on those cam / timing sensors. Your error codes could be the product of bad wiring / bad grounds, as much as anything else.
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. The question then becomes what repairs you are willing to undertake, and what your tolerance is for cost / benefit. And particularly, which part or subsystem sustained the damage. Many parts are readily and affordably replaceable. But if you find more significant damage to the crank, cam, block, valvetrains, it can very quickly get expensive and make it more economic to put another used motor in it - but that itself requires the mechanical skill and knowledge to undertake or even tell if the replacement motor is worthwhile.

I think your biggest trouble is a lack of mechanical knowledge. That's not a criticism, just an observation. You need to learn / research what **** matters more than others. None of the work is technically hard, just tedious. The internet is full of people and videos and technical references. And if this isn't your primary vehicle / daily driver, it would be a fine time for you to learn quite a bit by choosing to make the necessary repairs.


One last bit, on the earlier comment about spark plug tip erosion - the bent arm that hangs over the tip and creates the (critical) measured gap for the spark is called the ground electrode. Your #1 is horribly eroded / burned away. The 'tip' is the center electrode. Any break in the porcelain covering it - either inside the cylinder or outside of it - leads to a misfiring or inefficiently firing plug and a loss of power. and btw the shape of those tips appear to the newer platinum-type plugs. Older copper core plugs usualyl have a flat-ended cylindrical tip. And it's important when setting their gap to have the ground electrode at the gap be parallel as possible with the flat face of the center electrode. The newer platinum and iridium plugs use a totally different tip design.
And frankly overall your spark plugs are in horrific condition. A grab bag of garbage. I find it very hard to believe that engine was running well at all if the plugs were in it in the conditions pictured. Especially the two that are bent fully closed. Your engine was basically running on 3 cylinders. And you say you've had a CEL burning most of the time. No wonder.


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.

 

[normal_dave]

I think this may be the answer to any money pit questions...
"The body doesn't have a straight piece of sheet metal on it. I love it".

The Force is strong with this one...