Well, I got that liner out and did the soapy water test. The liner was just hung up on a bit of metal behind it. Probably not worth describing in great detail. It was hiding behind that real flexible portion of the liner that is a separate piece.

I'm not sure what to make of the test. It revealed a leak on the passenger side for sure. Toward the rear of the manifold. Like a tiny bubble machine. But on the driver's side, where the noise is most audible, I couldn't discern anything. So I'm not sure what to make of that. I've laid under the truck when it's making that noise, and it definitely is coming from the driver's side.

That green fitting on top of the EGR valve does create a little suction at idle; not much, but a little. Is that normal?

The guy who owned the truck before me ran 10w-40 in it. The first thing I did was change the oil. You are certainly right, you never really know what a truck has been through prior to you owning it. This truck appears to have been well cared for cosmetically anyway; the body is very clean. The guy I bought it from was himself the second owner. So who knows. I got it for a decent price and figured the tradeoff was figuring out what this noise was and fixing it.

Chia seed definitely has its drawbacks. I will admit. Not everybody can be Mr. T. The alfalfa and the omega--man, you are just plain trying to ruin my keyboard aren't you?

 

Honestly, for the amount of money I had to spend, I knew there was no way I'd be getting something perfect, or even close to it. I figured I'd have some work to do. This truck's body is pretty clean. The frame could use some POR 15. For the most part the truck runs ok. The bucking and hesitating started after putting in those new plugs; I think getting the plugs, wires and coils squared away will probably solve that. Especially given what you said about Autolites. But this other noise, I'm not sure. Those exhaust manifolds could certainly use replaced. But I'm not sure that lefthand one is making that noise. It did occur to me that perhaps my vacuum wasn't creating enough pressure to expose the leak. But I don't know.

 

if you're decent with motors etc, get a subscrition to alldatadiy.com or someone on here may have an active subscription. mine is expired otherwise you could use it..

 

Your vacuum should have been plenty. It doesn't take much air pressure to expose leaks unless you have one very bad one lol. I'm not sure what to make out of your drivers side leak test. Haven't heard of anything like that. Either it's leaking or it isn't. This test should of revealed that hands down. The noise, - other than what I described, I don't know. But with those plugs and it's misfiring, that engine will make all sorts of noises. If an engine isn't firing on one or two cylinders, those two cylinders will act just like a compressor and build air/pressure. Crazy things happen, some bad, very bad. Like don't lay under the truck when it's misfiring like that. The converters are getting fuel soaked and can explode. Get the right plugs in there, -seriously.

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Yea, same thing happened to me, - with a 99 in fact. It was a 5.4L tho. Installed Autolites and they heated up and misfired right away. That was before I had my education on spark plugs.

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I took a Mercury Marquis into the dealership about a year ago after it made that noise exactly as you described at cruising speeds. This vehicle has the same engine yours does. Turned out to be the converter. I'm not sure if it was the heat shield or if it was internal ? They replaced the converter free, - under the emissions warranty. Converter noise is popular amongst other forums abroad.

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The green line on the EGR. A little vac or suction is fine as long as it's not enough to lift the valve. When the EVR goes out, there's to much vac. It lifts the valve at all RPM's. If that's the case, idle would change as soon as the green line is connected. You can also clean the EVR filter. The filter is right under that cap that spins by hand. Sometimes the EVR gets noisy. That's normal and doesn't effect operation. The noise usually comes right after shut down as it purges residual air or vac in the system.

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10W 40 is very bad for the engine. Knowing that was used would make me want to compression test. That oil is TO HEAVY for this engine and will starve internals with tight tolerances.

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Chia -

I've had this key board the longest. Must be some kind of a record for me. I really like this one, it's cordless and the keys light up as I type. So far so good, but I have a pile of them in the closet. Not sure why I'm keeping them. Guess I'm hoping one day they may dry out. Tried using a Milwaukee heat gun once to speed up that process. Didn't work, after re-connecting the KB, I found that the keys were locked in place and wouldn't budge.. - I think I got it to hot ?

 

Btw, -compression testing procedure is in my sig below. If you end up going that route at some point.

 

I'd say there's no exhaust leak on the driver's side, then. That seems pretty conclusive. It sounds like what's happening with the exhaust is exactly what jbrew and others have said--the right side is going first. Probably that transmission mount could use replaced.

I was thinking about it, really I can't go too wrong replacing any of this stuff, because it really could all use replaced. But I think I'm gonna start with the plugs, wires, and coils. I just placed an order for them. I'll get them in and see what it does. I think it will clear up the bucking and hesitating.

I also wonder about that thump---I wonder if it was the converter that made that; like if fuel accumulated in there with the cylinders misfiring, and it popped off a few times. That sound just about made my toes curl. My more pessimistic side wondered right away if a valve had struck a piston---but I think if that had happened, the engine would not sound normal any longer at idle.

 

I haven't been driving the truck since it started bucking that one day. I'm borrowing a vehicle until the truck is fixed.

Lucky 13, thanks for the heads up on Alldatadyi---that looks pretty interesting. Something else I'd seen was the online motorcraft service manual Do you guys know which is better?

Yeah, I was surprised that guy ran 10w-40 in this engine---I mean, where in the world would he ever hear to do that? That was part of what went into my thinking wondering if that sound in the video was a wrist pin, or a spun bearing. Precisely as you say, I'm sure some parts got less oil than they should with that oil. We'll see.

Thanks for pointing out the compression test link. I'm sure I'll do that at some point here.

My computer is a laptop, so if I spray my keyboard, I'm in real trouble. Back when I used to work in an office, I knocked over a glass of coke one day straight into my keyboard. The tech support guy walked in, looked at it for about two seconds, then unplugged it without saying a word and dropped it in my trash can. Woops.

 

145,000 miles! It's not even broken in yet!

David
(241,000 miles on mine)

 

David, that's great. Did you buy your truck new or used? Any tips you'd like to pass on for achieving that kind of longevity? I sincerely hope I can get this truck squared away and make it last like that. Just gotta dig out a little bit here to get it started I think.

 

Sounds good, that will help allot. I bet that engine will appreciate the right plugs lol.

Your right with your assumption on the converters. Here's what happens, - If a misfire occurs, the unburned fuel and air mixture is pumped by the exhaust stoke into the catalyst, where it washes over the advanced coating on the catalyst honeycomb. The next blast of hot gas then ignites the mixture, driving up the catalyst temperature by as much as 800ºC and causing a marked deterioration in the catalyst, so that severe catalyst damage can occur very quickly. It may not always ignite on queue. wash and fumes can accumulate to a point of implosion (sort of speak).

Once you get it running on eight that will clear up, - BUT, your going have damaged converters from here on out most likely. They're like a big perforated brick inside, not sure how to describe, -like a sponge or chunk of Swiss cheese with a bunch holes or tunnels running thru. When it explodes like it sounds like it has, the brick breaks apart. That causes the kind of noises your hearing at cruising speeds. Not limited to, -they can make noises at any load or rpm.

 

Woops lol. I've went thru more phones that way, woops, DAMN! Usually drowned them in the center counsel in the truck. It got so bad at some point, - each time I'd spill something, I immediately look for my phone. Never could keep one for to long. Hell, they don't bounce very well either. DAMN!

 

I'm sure you will get it sorted out. Please post the answer when you get it fixed. If I can think of anything to look at, I will let you know. From following this thread, it looks like you have gotten some good advice already.
I bought mine brand spankin' new off the dealership lot. As far as maintenance goes, I have just done the usual recommended stuff at the proper times. Battery, Spark plugs, Air and Oil filters I stick with Motorcraft. Everything else that has worn out over the years is from Autozone, Goodyear or RockAuto. Engine (almost) runs like the day I drove it off the lot. I can still easily spin the tires if I want. Transmission is good, and last but not least the truck paint is still shiny and has no dents.
The only odd problem I had was the infamous no. 4 cylinder misfire. That was caused by the heater hose leaking coolent into the no. 4 spark plug well.
I fixed that by replacing the hose.
You take care of your truck, it will take care of you! And mine has. :-)

Good luck,
David

 

OR the cats could be clogged. run it real hard one night and see if they are glowing. mine were red hot.

 

Can damaged cats in turn have any adverse affect on your engine? Or is it strictly an emissions issue?

The plugs and stuff should arrive today; I only ordered them on Thursday; that's some fast delivery. I'm hoping to do that today, but i also have to fix our furnace; so it depends a little on how long that takes. Luckily we have a wood stove, and it's not bad out today anyway.

Thank you guys a lot for your thoughts and help. It has helped clarify things for me considerably. I owe you guys a beer for sure. Jbrew, I think I owe you two. lol

I'm sure I'll have more questions, too; this truck needs a bit of work. I think the brakes will be up next. I'd like to get ahead of that, before there's a major malfunction.

I'll let you know what the new coils, wires, and plugs do. I'll see what of these original noises and problems are left once that is done. l'm cautiously optimistic that this will fix most, if not all, of it. We'll see.

I don't have good luck with phones either. Like I had one in the upper pocket of my overalls, and when I undid the shoulder straps, of course the top flopped forward, and the phone slid out into the toilet. Not exactly a moment for my personal highlight reel.

 

And yes, before anybody asks, I replaced my phone.