2000 windstar deep engine knock

i have a 2000 windstar with 120,000 miles that has an occasional engine knock. i hear it mostly when idleing. sometimes it is loud, sometimes soft, sometimes you can not hear it at all. for example, last week we were driving in a suburban area with many traffic lights, you could hear it at one light and get to the next and you wouldn't hear it. the mechanic who i use says he has never heard one do this. he said it sounded like it was coming from deep in the engine. yesturday we were listening to it while it was ideling and the knock slowly faded away while listening. no perfomace issues.

If this is the classic engine knock, that can be corrected by the typical fuel and cumbustion related remedies, and it may be worth doing anyway to rule those things out. But if it isn't that at all, then one's mind unfortunately goes to mechanical breakdown of the crankshaft components, journal bearings, main bearings. Even the transmission should be checked for the noise. I have a vehicle that is believed to have a wrist pin noise that is only coming from one cylinder, but it is heard from the upper part of the engine, so I don't expect that to be your problem. You need to have it listened to from below with a mechanics stethescope or like to listen around for the source of your knock. Sorry, it doesn't sound too good to me from here :(

My '01 had somewhat of the same knocking sound and it turned out to be the 2 piece plastic upper intake that had come apart. At first I thought it was a bearing/ piston knock. Replacing it with a newer 1 piece design solved the knocking sound. I think the 2000 model has the same 2 piece upper intake.

I agree with road_rascal. I would check the upper air intake first. The top half is comprised of two pieces held in place by two plastic clips that shrink/warp over time and then the two parts rattle making a "knocking" sound. In my case, a 2001 Windstar, I just cleaned the two parts and glued them together with black sensor safe RTV silicone letting it cure for 24 hours before reassembly. I also did the isolator bolts, cleaned the ERG ports, etc. at the same time. No more "knocking" noise ater the fix which was 50,000 miles ago.

yes its the upper intake cover has defective rivets can replace for about 90 bucks check A1 autoparts on line

I would like to thank everyone for their post but especially road rascal, jgattian and schadd1971. They were correct. I printed all the post and gave them to my mechanic. He really did not think that could be it but said he would look and it was. He said it wasn't broke but loose and knocking. He did what jgattian did and so far so good. It runs quiet as a mouse.
Thanks again!

glad to here it....I had the same problem a year or so ago.....good deal

Good to hear it was an easy fix (hopefully cheap too). When I first heard the knocking sound on my van I almost shat my britches since it was so loud. This forum is the best!

I have a van that's a 95 that is having the SAME issue. Could someone get some pictures up of the issue or the defective rivets so I'll know what to look for?

The upper intake manifold issue mentioned here is for the 1999 and newer 3.8L windstar ONLY.
Your issue will be caused by something else on anything older.

I'm glad I don't listen to the first person that makes a claim. You know what, just ignore wiswind. Could someone get the pictures anyway. Just because it isn't common for a certain year doesn't mean that year didn't have the same issue.

You will need pictures from a '95 windstar....as that is the ONLY year that this particular upper intake manifold was used on the windstar.
Someone may know if this was used on the Taurus also.
The '95 3.8L windstar does NOT have the cross port intake......they started with that in 1996.

I am NOT saying that the problem cannot be related to the intake.....just that the particular issue with the 2 piece upper intake comming apart is a problem with the '99 and newer.
The '95 has a alluminumn upper intake manifold......the '96 through '98 has a single piece black upper intake manifold.
The '99 and newer 3.8L has the 2 part intake manifold that comes apart.

I am sorry if I sounded like it could not be a similar issue......just that your issue will not be helped by pictures of the newer upper intake manifold.
I really do hope that your issue is not a serious one.

Is your engine a 3.8L or a 3.0L? (fewer 3.0L windstars were made......and the 3.0L was more reliable.....which would further reduce people with personal experience with your issue).

I am experiencing what sounds like the same thing with my 01 windstar with 183000 miles on it. As it sounds like this condition is a "leak" does the vacuum pressure read less than normal? I am getting idle pressure around 15 and around 19 at higher RPMs. Also, does this condition worsen over time as the gasket's leak get worse? Any help would be greatly appreicated.

Thanks.