Contour Enthusiasts Group Archives Forums Branches Eastern Canada Knocking @ 4000 rpm

Okay here's the question for the day:

when I rev my 95' up to/past 4000 rpm, there is a loud knocking sound. I haven't been able to locate exactly where it's comming from however it's actually powerful enough to noticably shake the car. Any ideas?

cylinder mis-fires?

has anyone else encountered this?

Is it persistant or does it only do it once? For the record 4000 rpm would be just past the IMRC opening and could therefore be related some how.

It's pretty constant - I thought @ first it was just b/c of the cold, howver i tried it again after driving for about 30 minutes and same thing.

It sounds sort of like the mustang fast and the furious two - when they do the sprints to the pilon - @ least in regards to the knocking sound.

I'd be takin a good look at your oil. See if there is any shiny stuff in there.
i know my berring didn't start makin noise til around that RPM.
How many clicks?

Sounds like a known issue with some 95's. I had one, main bearings let go at 59900kms, got lucky back then (1997) and Ford gave me a brand new long block.

This is the worst case scenario, if the main bearings are shot, but that's what mine did, anything above 3500rpm gave a loud knocking noise, then eventually the valves would start tapping as the lifters were restricted of oil pressure due to the failure in the bottom end.