'99 LX 3.8 Bad Engine noise

The problems continue...Any opinions on an engine noise that seems to come from lower rear of engine? Changes w/ RPM, sometimes it stops, sometimes it changes intensity; rapping, tapping type so9und. Spun bearing? Loose flywheel? Any ideas out there? Thanks

Sounds like you may have a loose connecting rod (pun not intended, much). Connecting rods take the explosive force pushing teh pistons and apply it to the crankshaft. If the bolts holding the connecting rod to the crank work loose, then you will have a clanking-type sound. You will also have a limited amount of time before one part or another breaks and does some catastrophic damage to your engine.

At any rate, it sounds like a good reason to stop running the vehicle and getting someone to take a good look at it.

Sounds like you may have a loose connecting rod (pun not intended, much). Connecting rods take the explosive force pushing teh pistons and apply it to the crankshaft. If the bolts holding the connecting rod to the crank work loose, then you will have a clanking-type sound. You will also have a limited amount of time before one part or another breaks and does some catastrophic damage to your engine.

At any rate, it sounds like a good reason to stop running the vehicle and getting someone to take a good look at it.


Can a bad rod bearing produce a clanking sound that stops on occassion? BTW, the van is sitting in a repair shop, so it will not be driven.

I appreciate your comments and help.

If half the bearing crumbled, I suppose it could... is that what the shop is telling you?

If half the bearing crumbled, I suppose it could... is that what the shop is telling you?


I heard it for myself while the van was sitting the repair bay. Rev it up and the sound will sometimes stop. To me the sound was worse while standing under the oil pan.

Is your shop/mechanic 100% sure it's not one of the serpentine belt driven components making the noise? I've seen alternators, power steering pumps, idlers, tensioners, etc.. make aweful noise when thier bearings give up. See if the shop can get an oil pressure reading. Low oil pressure = a bad/spun con. rod bearing.
G/luck
Joel

Is your shop/mechanic 100% sure it's not one of the serpentine belt driven components making the noise? I've seen alternators, power steering pumps, idlers, tensioners, etc.. make aweful noise when thier bearings give up. See if the shop can get an oil pressure reading. Low oil pressure = a bad/spun con. rod bearing.
G/luck
Joel

Actually no one is certain about anything yet as they have not really looked at it yet-it went in late Friday afternoon. Monday we will know more. Thanks for your comments, though.

I think I know what your problem is and it is relatively cheap to fix. Is your Windstar equipped with the "camel hump looking" upper intake manifold? If so start the engine and leave it in Park, open the hood and put your hand on top of the intake (camel hump looking if equipped as such). Then with your other hand rev up the engine and change rpm ranges while feeling then intake. Ford had numerous problems with the upper intake separating internally..... it has an internal arrangement of plastic induction runners that is plastic welded to the outside shell (camel looking intake). If you can "feel" the noise then chances are you have an intake that has separated internally. To remove you have to take off the wiper arms and cowling pieces. Then you will be able to access and remove the upper intake. It all makes sense when you get the intake off. Hope this helps. I watched a guy in the dealership (I'm a former tech at the local Ford dealer myself) condemn an engine and sold the job to the customer only to find the real problem was the intake separation described earlier. I quit the dealer as a Master Tech and went to work for the city.... got tired of the up and down in pay from working commission and the crappy benefits. I'll check back later to see if you have any other questions about this.

I started to suggest the same thing, but the fact that the sound seemed to be coming from the lower part of the engine convinced me it wasn't the upper intake.

Its certainly worth a try.

I think I know what your problem is and it is relatively cheap to fix. Is your Windstar equipped with the "camel hump looking" upper intake manifold? If so start the engine and leave it in Park, open the hood and put your hand on top of the intake (camel hump looking if equipped as such). Then with your other hand rev up the engine and change rpm ranges while feeling then intake. Ford had numerous problems with the upper intake separating internally..... it has an internal arrangement of plastic induction runners that is plastic welded to the outside shell (camel looking intake). If you can "feel" the noise then chances are you have an intake that has separated internally. To remove you have to take off the wiper arms and cowling pieces. Then you will be able to access and remove the upper intake. It all makes sense when you get the intake off. Hope this helps. I watched a guy in the dealership (I'm a former tech at the local Ford dealer myself) condemn an engine and sold the job to the customer only to find the real problem was the intake separation described earlier. I quit the dealer as a Master Tech and went to work for the city.... got tired of the up and down in pay from working commission and the crappy benefits. I'll check back later to see if you have any other questions about this.

Hi! This is one of the first things I checked for using the screw driver stethoscope method. I could not discern specific noise coming from the plenum. As the person said below, the noise at the pan is pretty loud. Believe it or not the shop has not been able to look at it yet. I really appreciate your experience and comments so I will suggest the shop look again at the loose plate in the plenum possibility. I originally thought it was the pwr steering pump. It was slinging grease/oil and the steering was very labored. I know the drill on Windstar steering systms by now. I will keep you posted.

I ask again; can a rod bearing noise start and stop?

I am very curious to hear what your repair shop concludes is your problem. I have exactly the same issue on my 2000 Windstar. Please let me know what you find out. Thanks!

I am very curious to hear what your repair shop concludes is your problem. I have exactly the same issue on my 2000 Windstar. Please let me know what you find out. Thanks!

I hope you got my email. If not, the repair was very large if you have broken roller lifter guides. Depending on the extent of the damage you can probably count on replacing the cam, replace damged roller lifters (I had two), new lifter guide, plus all the gaskets and and seals involved in taking the heads and front cover off, plus removal of the engine. About 16 - 20 hours labor.

Please get back to us if this is, in fact, the repair you had to make. Thanks.