noise."Explorer(ererer etc.) · 2:57am Oct 24th, 2020
On the “Well there’s your problem” podcast, they constantly promise that their next blog post will be about the Tacoma Narrows Bridge.
It never is.
Totally unrelated to the intro, the blog posts about my epic vacation are totally coming soon (with pictures and movies), but first we gotta talk about the Explorer.
I vaguely mentioned it back when I was complaining about cat radio failure. And I realize that this is the internet and I totally could have edited that past blog post to reflect the current sad state of affairs, but I swear to you on a pile of cupcakes I didn’t. I said that “the customer was on a budget, so some things that ought to have gotten replaced didn’t. That might come back to bite us later, honestly.”
You’ll never guess what came back.
“It doesn’t run well,” was the complaint, and boy didn’t it. The scan tool was no help. On startup, it ran kinda rough, and then it sort of smoothed out, sometimes. Taking it for a test drive . . . well, the scan tool died, but I didn’t need the scan tool to tell me that it didn’t make power, it misfired, and it got unhappy over 35mph (like, 60km for the rest of the world). Really unhappy--I took an abbreviated test drive and wondered if I’d make it back to the shop. I did, but the scan tool didn’t; battery died before I got any useful information.
Said Explorerer spent the rest of the day being a thorn in our side. Wasn’t much I could do until the scan tool recharged, and when it did, the results were inconclusive at best. Some of the numbers were not quite right, but I ran into the age-old dilemma of that being a cause or symptom. Mass airflow reading’s a little bit low, but maybe that’s because it’s misfiring. Fuel trims are skewed, but that could be due to how poorly it’s running. Volumetric efficiency isn’t great, but it’s not bad enough to call a mechanical problem just yet.
It usually misfired on four on startup, as well as two and or three, but sometimes not. Six was questionable, it came and went. Five and one tended to be okay, but not always. Problems didn’t seem to land on one bank or one cylinder, and sometimes it’d misfire on a cylinder or two on startup, only to pick them up after it had run for a little bit.
[On V-engines (or the less-common opposed-piston engines) a problem on only one side but not the other helps diagnostically, compared to a problem on both sides of the engine. If you’re working on your Bingo card at home, Ford numbers one side of the 4.0L 1,2,3, and the other side 4,5,6.]
Knowing that we’d just put an engine in it, there was always the thought that something hadn’t been assembled correctly. Knowing that said engine had come from a junkyard and that some of the stuff that ought to have been replaced wasn’t also a consideration. Given the time and budget allotted for this project, there were a lot of junkyard parts still on this engine, either because the ones on the vehicle didn’t survive removal, or because it was difficult to change them. And there were parts that ought to have been replaced that weren’t. The intake gaskets, for example. They looked okay, but maybe they weren’t. Maybe they were letting air through that the mass airflow sensor didn’t know about, leaning out the fuel/air mix, and maybe the truck was trying to adapt but couldn’t.
Fuel trims didn’t look that weird, though. They weren’t right, but they weren’t that far wrong, either.
Plus, we don’t know what took the old engine out. We know it didn’t have compression, but we don’t know why--we didn’t tear it down. Maybe a blocked catalytic convertor slagged the valves, and maybe it’s still blocked . . . that would affect fuel trims and mass airflow readings.
Or maybe it’s customer-caused. Abuse is a possibility--could be the guy really liked doing hole shots with his Explorererer and losing one engine wasn’t enough of a deterrent. We see abused cars.
Maybe something more mundane. Did the problem start when he fueled it? Where did he get his fuel? Was it from a reputable gas station, or did he find a bucket of something that smelled like gas in the backyard and though he’d save a few bucks by dumping it in and seeing what happened? In the above photo, if you look closely you’ll see a fuel pressure gauge and a hose leading off where one might take a fuel sample; you’ll also notice a little bottle with two pressure gauges--that’s a BG fuel system tune bottle and while it’s meant to put their special proprietary blend of eleven herbs and spices fuel rail cleaner in, you can also install straight gasoline, set the pressure appropriately, and prove beyond a doubt that the problem is (or isn’t) a fuel quality issue.
Spoiler alert, it wasn’t a fuel quality issue. Or pressure or volume--it had the fuel it wanted.
In fact, all the sensors and modules on the engine were working as intended, and all the readings were true. I’d be lying if I told you that nothing was wrong with this Ford, because of course something was. But it wasn’t the engine or any of the sensors and it wasn’t anything that got did or didn’t got did when a new engine got planted in, nor was it a failing on the customer’s end of things.
As the NTSB once wisely said, “Loose electrical connections or mechanical fastenings have caused numerous derangements of electrical equipment." While this malfunction doesn’t quite fall into the loose connections or mechanical fastening category, it certainly was a derangement.
In the picture, everything is straightened and neat, and while those bare wires will obviously be a problem in the future, they’re not touching, so the electricity goes where it should. In actual fact, the four of them were all kinda wrapped around each other and sometimes arcing and sometimes not.
Now, y’all can figure out that bare wires touching that shouldn’t are a problem, I don’t have to tell you that. What I do have to tell you (unless you’re a Ford expert) is what those wires do. One of them--without consulting the wiring diagram, probably the yellow one--is a power wire, and the other three are computer-controlled ground wires. One of them lets pixies in, and the other three let them out.
And what are those pixies doing? Angrily zooming around a coil of wire. Those wires are the ones that run the ignition coil. This Ford has a single coil that runs all six plugs, and they’re paired. 1/5, 2/6, 3/4, IIRC. So when the PCM grounds (let’s say) the white wire, coil 2/6 ought to fire plugs 2 and 6 (one of ‘em isn’t on the ignition stroke of the four-stroke cycle, which is why this is a waste-spark system . . . electricity is cheap, and when this engine was designed, coil-on-plug wasn’t)*.
Now, if those wires are bare, and if those wires are touching, when the TCM grounds (let’s say) the white wire, coil 2/6, that might not be the coil that actually fires. And while half the spark going to a cylinder that doesn’t want it was an intentional design, all the spark going to a coil that doesn’t want it wasn’t. Or the power wire being grounded out . . . when and how they touch was largely based on engine vibration, and as you can imagine with engine vibrations already being higher than normal due to misfires, it was anybody’s guess where the spark was going to go and what it was going to do. And if it was random and not always right at idle, imagine what happens when the engine RPMs and load go up. Spark’s going everywhere and anywhere and the little engine couldn’t.
____________________________________________
*Ask anyone who owns a modular Ford engine about coil-on-plug technology. We stock one COP, and it’s for that engine.
I’ve showed you before in a blog post a sad PCM caused by a coil failure . . . too much current, and the driver in the PCM melted. In fact, we currently have a Jeep with a similarly-designed ignition system in the shop, and the 3/6 coil driver in the PCM is done. Verifiably so, and if the customer authorizes a new PCM, I’ll peel the cover off the old one and take a picture if it’s interesting (crispy).
I’d like to pretend that it was my brilliance that solved the sad Explorer(erererer)’s issues. That I looked at all the scan data and the fuel system data we had with our fancy gauge and fancy Pepsi bottle full of fuel that we shook around and sniffed and decided that it smelled okay, but it wasn’t. It was getting late in the day and we were grasping at straws and it probably wasn’t the ignition coil but we had an extra known good one and it was easy enough to change, so why not give that a shot and see what happens? And of course a new ignition coil wouldn’t fix this, but it did give me a new opportunity to unplug the connector and see a lot of bare wire right next to the connector.
I’d like to imagine that it didn’t look like that when I dropped the engine into the Explorer, and maybe it didn’t. Maybe in the few days between engine install and comeback the mice got at the wires--mice love wires-- and did the right amount of damage to make it not quite undriveable and not quite predictable. And maybe they did. I would like to think that even if I was putting an engine in a vehicle as quickly and cheaply as possible, I’d notice bare wires on a connector I had to plug in as part of the assembly process. But I don’t know. Maybe I didn’t.
At the end of the day (literally), the wires got fixed; they got new insulation out of a bottle (liquid electrical tape FTW). The customer didn’t get charged, and while in one sense we (by which I mean mostly I) spent more hours on diagnostics and head-scratching and theorizing than this ought to have had, it went out the door running well again. Faster, in fact, than the Land Cruiser also mentioned in the blog post which is back at the shop because it needs an oil dipstick tube and until recently the only one I’ve been able to locate would have to be shipped from Australia by FTL . . . I got a list of US-based Land Cruiser specialists and one of ‘em had one, and we got it today and it looks right and rust-free, so that’s a next-week project. Turns out the Australia one likely would have been price-competitive 
To all you old-timers out there, I have to imagine that a mechanical ignition (distributer cap) vehicle never would have did what this Explorer did. That no matter how bad the cap or rotor got, it wouldn’t have sometimes fired the wrong cylinder, maybe the very wrong cylinder. And to all you young computer guys out there, a really modern car would have known that it sent a command to one coil and said coil didn’t act on that command. In fact, the Jeep I briefly mentioned above (newer than the Explorer) did set a specific code for coil malfunction (insufficient spark ionization) even though it’s got the same six-pack idea on it. And those of you who are familiar with the Ford 4.0L SOHC and know where the coil pack lives and where the wires are might also be gloating, thinking that you’d see the problem straightaway--and maybe you would. Maybe when presented with a vehicle with multiple cylinder misfires that moved around, I ought to have figured it was an ignition problem right out of the gate.
I could counterargue that in a general shop like ours, I’m not a specialist, I’m a generalist. I know a lot of things passingly well, but not a lot of specific things on an expert level. One of my buddies made a fair bit of cash at a Chevy dealership by being the guy who could work on non-GM cars. I don’t know why you’d take your Dodge to a GM dealer, but for people who did, they were well-served by a mechanic who came from Firestone and wasn’t scared of Dodge brakes.
I could also mention as one of my trainers did that when you’re stumped, you need to step away and look at the problem with fresh eyes. I had in my mind that we slapped an engine in this thing on a budget, an engine from who knows what, and it didn’t get all the install parts I’d recommend (intake gaskets, etc.), so maybe when it came to the comeback I already had an outcome in mind (’the engine you bought is junk, boss.’).
Or maybe the moral is that a stopped clock is right twice a day; if you stumble into the solution you take it. After all, I did (eventually) find the bad wires, and I fixed them, and the customer doesn’t need to know that we were rummaging around in the box of parts which are probably good for a coil to try out. All he knows (unless he reads my blog posts) is that his truck ran bad when he dropped it off, we fixed some wires, and now it runs well. And we didn’t charge him for that fix, either. I don’t know how my boss framed it, but thinking back on my recent phone experience, I got upgraded for free because they couldn’t fix my old phone and while having to buy a new case unexpectedly was not on my radar screen, getting a two-years-newer phone for free wasn’t, either.
The Explorererererer left and the customer was happy and that’s what matters. Diagnostically, it could have gone better; repair-wise, it could have been a bad junkyard engine and I’d be pulling it again and while I’m paid by the hour, I still would have been tilted for the whole process and probably have also written a whole blog blaming my misfortunes on my boss. Somehow.
Ask me about how he broke the garage door.
In the interest of full disclosure, the Explorer comeback was within a week of the engine replacement--I could look at the date of my previous blog post mentioning it and give you an exact date, but let’s be honest, 2020 has been one of those year where each month was a year long and each day in each of those months was a week and if you do the math 2020 has been a garbage fire that started in the 60s and just burns and burns and burns. Time has no meaning.
But
But the Explorer runs now, and drives, and the customer hasn’t brought it back. And that, my friends, is a victory.
If engineers built buildings the same way programmers wrote computer programs, the first woodpecker that came along would destroy civilization.
--Weinberg’s Law
The rodents are coming for us:
https://cybersquirrel1.com/
So, when more Onto the Pony Planet, and please don't say well into 2021.
In the book The Reckoning, the author said that post WWII, Japanese car companies made the guys that designed the cars work in the dealerships repairing cars, on the assembly line building them, + the sales floor selling them before they were allowed to design cars.
Frayed wires? Apollo 1 and Swissair Flight 111 sympathize.
Ah, you listen to that too? :)
"or the less-common opposed-piston engines"
Oh, do you mean flat engines, or have you encountered cars with actual opposed piston engines? I think I recall hearing about some modern opposed piston automobile engine... I don't recall any details, though.
...What happened to those wires to cause that damage?
[reads on]
Ah; sorry about the mystery.
(Though would mice really leave such (relatively) nearly aligned patches of insulation stripped all the way around the wire?)
Whatever the details, though, aye, congratulations on the victory. :)
Most Ford engines are numbered like that. And Mercedes. But there's one Toyota (I think) V6 that is also that way, contrary to the rest of their motors. Maybe it was a Honda, can't rightly recall. That fucked me up. I was adjusting valve lash, and they were so helpful by putting cylinder numbers on the camshaft sprocket, so you'd know which one was TDC. Well, turns out, if you think the cylinders are 135 and 246, you'll have a really hard time of it. Which is funny, because if they hadn't stamped the cylinder numbers in the sprocket, I wouldn't have been confused, because I would've just looked at the camshaft lobes lol
As you know, it's those little things that really get ya.
Gee, I wonder.
I'd be willing to put money on it being the timing chain. In fact, we just lost one of those 4.0L's to a t-chain a couple weeks back. This guy always has shitty cars. He had a rustbucket beater Explorer, and he came in one day for something quick and I heard the engine a-rattling, and I was like 'hey come back tomorrow so we can look at that before the timing chain breaks.' Well... it didn't last that long. We junked that heap and sold him a Dodge Journey, which was real clean, well-equipped, and probably the nicest car he's ever owned. I'm a little upset that the body shop we had paint the fender painted over the pinstriping on the driver's door, what a bunch of clowns. But still, it's a nice car.
To be fair, that's more or less how I imagine most repair shops work: Mechanic pokes the vehicle for a few hours, he rummages for some parts, then hits it with a spanner and the engine block falls out.
Hah! I was guessing on faulty wiring, and for once I was right!
What are hole shots?
"I'm not saying it was Pikachus, but it was probably Pikachus."
—Admiral Biscuit, 2020
5384614
Counterpoint: If people had to live in computer programs, the people telling the programmers what to do might have a better understanding of what is and isn't a good idea.
5384811
i agree mice love wiring but i had a tractor drug in to me for a no run no start and part of the wiring was out right dead.
the short story.............Groundhog, claimed up the tire i am thinking and desired to make a nest in the man wiring junction area.
I heard somewhere recently that it was still possible to run 8086 code on recent Intel CPUs at least due to the tiny emulator etc needed? Would be nice if they could actually run the current code as reliably?
Flexible wires are all well and good for handling vibration, but when the insulation work hardens and cracks and the Gallium runs out making new conductive paths, then things get Very intresting?
Sounds like one of the classics.. Sure, we had a robin in the air intake, bats in the air filter, mice in the exhaust and a skunk in the passenger well, but there wernt nothing stopping it working?
I mean, is there really that much to say about Tacoma Narrows?
"Don't forget to account for mechanical resonance."
Bam.
When I was a kid back in the 70s, dad had a '73 Jeep J10 (or maybe J20) pickup. Had it until the mid 80s. I remember one of the things about it was the awful distributor. The cap in particular was a constant source of trouble. Had a little window in the side covered by a sliding metal shutter for some adjustment. But it wasn't water tight and if you ran through a decent puddle water could splash all the way up to the dizzy and wreak havoc shorting the points. Also a couple times it developed cracks and the spark would arc between the towers firing the wrong plugs.
The 70 Monte Carlo I had in HS once had bad plug wires. Couldn't figure out why it was running so badly until I watched the engine running in the dark and the wires were arcing all over the place. Looked like Christmas lights flashing.
Ow, my head.
You know those “pony x gets replaced by/turned into object y” stories? Someone should write “Rainbow Dash gets replaced by the Tacoma Narrows Bridge.”
5384640
Software companies often use their own products everyday as a "dog food" strategy- eat or use what you make so you know it's good.
5384614
True fact, not that long ago I had a woodpecker hanging out on the screen on the window by my computer, just looking in at me. Biding his time.
5384636
The squirrels will doom us all.
5384638
When I have enough free time to work on something substantive . . . work has been insane the last couple months, and it’s showing no sign of letting up, and in what little free time I have, there are some home projects I need to get done before the winter.
5384640
If true, that’s a smart idea. Maybe why they generally build better cars.
5384643
Yeah, you ain’t kidding. Bad wiring--no matter what the cause--can lead to all sorts of disasters. Or, as GM calls them, ‘thermal events.’
5384666
"or the less-common opposed-piston engines"
I did mean flat engines, not a true opposed engine.
I think the engine you’re thinking of is Achates’ opposed piston engine for Ford. I haven’t heard anything about that engine for a couple years, so they might have shelved it--I suspect that they’d have problems meeting emissions standards for an on-road vehicle, but I don’t know. A lot of new automotive tech turns out to be kinda flash in the pan.
Yes, they might. A lot of times, mouse damage is localized, There’s one bundle of wiring where they want to chew, and that’s what they go after, and in my experience, they do tend to leave patches like that. A lot of times, they’ll gnaw through the copper, too.
Thank you!
5384691
Except for Subaru (probably), I can’t think of a single automaker where all their engines are numbered the same. Just enough of them to give you confidence that that’s how Ford (or Honda or whoever) always does it, so this must be cylinder 2 or what have you. Like, I don’t remember which GM engine it was, but I was looking through Mitchell for firing order and cylinder identification and it said “All V6 engines except X.”
Doesn’t help that most of the automakers share engines across brands now and then. I blew a Firestone manager’s mind when I told him that while we couldn’t get parts for some Chrysler with a 3.oh no from the Chrysler dealer, Mistubishi had them in stock. Or the Villager we fixed with a genuine Nissan exhaust manifold . . . discontinued from Ford, Nissan had ‘em in stock.
I should have suspected ignition sooner by the way everything was moving around, but hindsight’s 20/20. . . .
Oh yeah, that’s what we assume, too. But once we found the lack of compression, we didn’t do any other tests nor any further teardown (besides what was required to transfer parts) so we don’t actually know. And I don’t recall this particular Explorer having a chain rattle the last time we’d worked on it, which of course doesn’t preclude sudden, catastrophic failure, but in my experience, the 4.0s tend to have chain rattle on startup for a long time before things actually fail.
One of our regular customers had an Explorer that was pretty nice except for the rattle, and we were able to convince him to trade it in for something different before ultimate failure, so I think he did okay. Especially if he made sure it was nice and warmed up before taking it to the dealer.
We did have a guy with a CX-9 (iirc) with the DI engine that we got running again after it carboned up so bad the valves stuck open. We told him to sell it as soon as possible. Less than year later it came back, and this time internal parts went through the block, and he couldn’t afford an engine.
I painted over pinstriping on a car once and I regret it.
5384720
Actual diagnostic instructions often include the step of ‘replace with a known-good part.’ The problem for a smaller shop is that we can’t keep a vast collection of known-goods on hand. Sometimes new parts get ordered from our supplier as test parts, and often get returned when that didn’t fix it or if we don’t trust that part for a lasting repair (Dorman’s Fuel Pump Driver Modules come to mind, plus the Ford one is actually cheaper, but we can’t get it as fast).
I haven’t had an engine fall out that I didn’t mean to, not yet anyway.
5384743
Faulty wiring can cause all sorts of weird problems. Worse, sometimes they come and go, which makes diagnosis harder. Currently got a Silverado with an intermittent problem or maybe I fixed it inadvertently by unplugging the module and plugging it back in again.
5384992
If you want something done, ask a busy man.
5384808
5384811
Yes, exactly.
Let me never tell you how at least one aircraft got programmed.
5384829
We had a truck at the dealership that had that happen to the rear wiring. Funny thing was, the woodchuck was still there.
5384843
I’ll be honest, with all the millions and millions of code operations surely going on in my Lenovo, it rarely malfunctions.
Yeah, and on cars the heat cycles are also also a problem. Some of the materials they use don’t hold up like you’d want them to.
5384859
Part of the reason the Mackinac Bridge was built the way it was.
Another valuable lesson would be to pay your bridge insurance policy and not pocket the money figuring it’s a new bridge, what could go wrong?
5385075
Forgot about the insurance thing.
5384892
GM’s flat distributer caps (on the computer-advance 4.3, 5.0, and 5.7 (and probably some other engines of that vintage) were also notoriously bad. They’d get water vapor in ‘em and the spark would go the wrong place, if it went anywhere at all. GM included little screens to let the water vapor out but those didn’t work; if anything, they trapped more of it in. Lots of techs would just punch those screens out in the hopes that the vehicle would run for longer before needing another cap.
I’ve seen that before, too. We also sometimes spray water on suspicious plug wires, and boy do some cars light up when you do that.
5384900
5385079
First thing in the morning,
Just as the sun is dawning,
You spray the distributor cap,
And then you turn the key.
5384935
So basically she gets turned into a pile of scrap metal at the bottom of the Tacoma Narrows, eventually becoming an artificial reef?
5384968
That’s not a bad idea. Never heard of it called a ‘dog food’ strategy, though.
5385094
Yeah. We use it as a verb. "dogfooding"
Ah, Epic Mechanical from Admiral ... it was interesting to read, especially after in our last phone talk my friend Vlad tell me a bit more about working with software/computer side of car engines ....
I tend to run software I at least compiled for myself, because I have uncommon by now x86-32 Slackware - and most of precompiled binaries for video editors and renderers tend to be x64 - they surely often works better when compiled this way on bigger projects, but for me old architecture still working (because effectively with Linux I can have 64-bit kernel and 32-bit userspace. So, all 12 Gb of ram and hardware virtualization for both x32 and x64 guests in qemu works ... and some kernel-level optimizations also get compiled in this way). This doesn't make me developer (I can spend a day modifying just one little file) but still I prefer to read some maillist over, say, watching cinema ...... Even if problems discussed on mail list all related to movie decoding and playback! :}
5384994
Well, the book is 30 years old, IDK that they still do that. But yes, that is what I read. ICR who invented the process used, but IIRC, but Japanese car companies were the first to use the modern process of applying rust proofing & American car companies were the last companies in the free world to use it. (It cost a LOT to convert the assembly lines.)
5385010
You don't know what you're missing then.
Ah, Tacoma Narrows Bridge; used in Physics classes as an example of how not to build a bridge...
5385090
I can’t believe that until half a minute ago I have never ever ever thought about whether freshwater reefs/freshwater coral are a thing.
5384998
Ah, thanks.
Ah! Yes, that name rings a bell; if it wasn't that I was specifically thinking of, I believe I have heard of that, and watched a video on it, as well.
Hm. Do many, or any, diesel passenger cars use diesel exhaust fluid, if you know?
Huh. Curious. Well, thanks!
:)
5385182
huh . . . you learn something new every day
5385197
I don’t know how it is in other parts of the world, but the software side here in the US is mostly mandated (what you see and how you interact with it), with each automaker having their own twist. Just yesterday I scanned codes on a Mercedes and they came up with no results on the computer because what the scan tool is giving me and what the computer database has are two different databases, and there’s something else I need to ‘translate’ them--Germans have their own weird code architecture which is likely very logical, but I am not familiar with it. I didn’t have enough time on that vehicle to try alternate ways to get the info I want, although I know I can (legal mandate).
Meanwhile, I’m an off-the-shelf guy who customizes some peripherals to his personal preferences . . . the only ‘technical’ thing I’ve done in 10 plus years on a computer was plug in more RAM.
5385201
I’m skeptical about rustproofing (and it might be a process thing); the domestics were doing it since the 70s by dipping the cars in a bath--one of the problems with the Vega, they often got air bubbles in the front fenders, which meant not rustproofed. Meanwhile, some Japanese cars of that era rusted as you watched . . . in Michigan, at least, pre-90s Nissan trucks are all gone, nothing but (rust) dust in the wind, while there are still a fair number of domestic trucks of that era kicking around.
Not that I’m claiming the domestics were great at it; all of my fleet has from some rust to catastrophic rust, but for all the recalls that my vehicles have, none of ‘em got one for the frame rusting through and breaking (Toyota Tacoma).
5385231
You’re probably right.
Best I can offer is on fire while driving, and that’s happened twice. Also complete brake failure; that’s also happened twice.