Connecting rod bolts
 

I've got a light knock that I hear around 2000 -2500 rpm that's driving me nuts. Above that rpm, there's too much other noise for my 1/2 deaf ears to hear it.


Not sure what it is, but I want to pull the rod caps and check the bearings. The last owner lost an oil cooler hose, but I don't know how far the car was driven after the hose let go.


Anyway, since the rod bolt torque is so many ft/lbs plus 1/4 turn (or something like that), I'm wondering if the stretched bolts are one time use and should be replaced.


Thanks in advance...

Re: Connecting rod bolts
 

Is it a consistent knock? Do you here it at lower rpm? Have you checked your Dual Mass flywheel? Those will make the motor sound like it it knocking.

Does this happen when the motor is cold? Warm? Both?

Re: Connecting rod bolts
 

Tensioner?

Re: Connecting rod bolts
 

Knock is consistent either cold or hot.
Driven about 1000 miles since I bought the car, hasn't gotten any better or worse.
Only hear it at lower rpms, 2000-2500-ish, only during acceleration or under load. At higher rpms, there's too much road noise to hear it.
No knock while steady cruise, coasting or slowing from what I can hear.
No knock at idle.

Re: Connecting rod bolts
 

Can you capture the sound on video?

Re: Connecting rod bolts
 

Don't think so. Quiet at idle or revving in neutral.


Only under load/acceleration.

Re: Connecting rod bolts
 

Already tried the video thing. Phone can't pick it up while driving. It's not that loud.
Sounds like a quiet version of a single rod knock.

Re: Connecting rod bolts
 

Stethoscope might help to pin point location of noise too? Might be there at idle just not heard

Re: Connecting rod bolts
 

Seems like the rod knocks I've heard could be heard even at low RPM's. But (fortunately) I haven't heard many.

Re: Connecting rod bolts
 

Yup, already tried the Stethoscope, both at idle and higher rpm.


Couldn't hear anything without the engine loaded.


So, back to the original question..... are the rod bolts reuseable, or do I need replacement bolts?