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what do you guys think

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Old 05-17-2012, 07:10 PM
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Default what do you guys think

very low oil pressure, wont go over 45 and struggled getting home.

take a listen and tell me what you think. full rebuild or what?

http://s1213.photobucket.com/albums/...t=feb6a32c.mp4
Old 05-17-2012, 08:51 PM
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It was like an episode of Ghost Hunters. I had to listen to it several times, but I think I heard your engine say, "fuuuuck".

You definitely have some gremlins inhabiting your engine.

Seriously though, it's hard to tell, but it with a sudden drop in oil pressure I'd suspect something pretty serious. It sounds like everything in there is running on dry and metal-to-metal. Like more than just one cylinder or set of valves. Even if it were initially something like a failed oil pump, the continued operation likely cooked the engine.

As a first step, I'd pull the oil pan and take a look around. If you don't see anything obvious (broken parts, metal bits in the oil, holes, etc), pull the valve cover. Again, if nothing obvious, replace oil pan and fill with oil. Pull distributor and use a flathead in an extension in a drill to manually turn the oil pump. Make sure you've got plenty of oil making it to the top of the engine.
If you don't, you could have anything from a failed pump, to a clogged pickup, to internal catastrophic damage that may not be obvious. The question is, did low pressure cause the damage, or did some sudden internal failure cause a clearance change (crank/cam bearings) that resulted in a drop in pressure. Chicken or egg?

If you don't have pressure, you may get lucky, just have a failed pump, replace it, and be able to salvage some usable life from the engine, but I'd put your odds at 30% or less.

I feel for you. And I would have had the same reaction or worse.
Old 05-17-2012, 08:56 PM
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Any CELs?
Old 05-17-2012, 09:33 PM
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well the motor does have 224k on it. its probably time it gets a rebuild anyway
Old 05-17-2012, 10:56 PM
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Poor pressure means your rod bearings aren't getting lubed. Pressure comes from good tolerances, primarily from the rod bearings.

Let me add, pressure problems can be caused by a bad pump. If you drop the pan for the pump, plastigauge a few bearings. That will tell you if they're in the ballpark.

224,000. Not bad. Still salvageable. Slap a diesel sticker on her and welcome to the 'damn this 4.0 is a loud rattler' club. We have jackets.
Old 05-18-2012, 01:05 AM
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The oil pressure and some knocking aside, what the heck...is that,... an exhaust leak? Ir is there a little by-plane in there? Put some beano in there! Lol. Hard to say but I'd listen around with a hose and try to find where that farting sound is coming from. Maybe something with the manifold is why it won't run right. Check the tale-pipe for potatoes.

Total long-shot, but the torque converter bolt's are known to loosen and cause a knock.
Old 05-18-2012, 01:20 AM
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Last time I heard a pfffffff sound like that, it was exhaust leaking from anywhere it could be forced out due to a plugged cat. Is the exhaust flowing freely out the tailpipe?
How low is the oil pressure?
Old 05-18-2012, 05:31 AM
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Can't watch the video again.... The vacuum line to the brake booster will hiss loudly if it's off. RPM will be about 1850 too....
Old 05-18-2012, 09:36 AM
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Originally Posted by Radi
Last time I heard a pfffffff sound like that, it was exhaust leaking from anywhere it could be forced out due to a plugged cat.
Can't say I remember hearing that sound, but I was thinking along the same lines. ^^ "potatoes!"

You could google "vacuum test for restricted exhaust" or something like that. Once I loosened the header pipe flange nuts to allow a leak there and Bingo! Had power.
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