2006 Civic Bearing sound at 3.5k

[shefler29]

2006 Civic 1.8L Auto, 240k on trans/chassis. 150k on motor (cracked engine block issue, Honda defect)

So I have this bearing sound only between 3.5k and 4k RPMS and doesn't matter what gear I'm in. So at first I figured is was the idler pulley since it wasn't that tight when spinning it by hand. That obviously did not fix the issue. I've tried running the car with no serpentine belt to see if it was one of the other pulleys but I still get the same sound. There has to be load on car to make the sound.

It will NOT make the sound while revving the motor in neutral (standing still or rolling down the road) or if the car is on jack stands and in gear. I know not that is not the safest thing to do but I can't figure this out.

Any idea on what may be the issue or another way to diagnose it without a dyno? The sound has been going on for about 20k. I drive 50k a year in the car for work.

 

[michaelluscher]

Engine/trans mount rattling around under load?

You weren't eligible for a new short block from Honda?

 

[Rand]

timing chain noise?

unrelated but my 2002 ranger had a timing chain issue that was only at a certain rpm under load.

 

[shefler29]

Originally Posted By: michaelluscher
Engine/trans mount rattling around under load?

You weren't eligible for a new short block from Honda?


Honda replaced the entire motor for free since the it overheated and basically melted. I had the car for 2 months at the time.

I think me a friend just figured it out.. We where able to hear the sound if you revved it quickly in neutral for a split second. The sound was coming out of the exhaust which may be a clogged Cat. When inside the car it sounds like it's coming from the engine which to me would make since because the cat is in front of the motor.

I'll report back if that's whats causing it.

 

[dlayman]

If you had a clogged cat, wouldn't you get a CEL? The previous generation Civics are known to develop cracks in the exhausted manifold near the oxygen sensor. Don't know how different this generation is, but the initial symptoms were similar to what you describe.

 

[Yup]

Weird, I've had a CEL for a CAT recently pop on regularly (every couple weeks) and I too have a high pitched whining sound. But with the hood open at cold idle it's definitely coming from the pulley area. At least sounds like it. Figured it was a bearing but none are loose or grind with the belt off...so...

I haven't had the CEL after adjusting the valves (some were way out of spec) for 4 months. I'm thinking that might've been messing something up.

 

[shefler29]

Originally Posted By: dlayman
If you had a clogged cat, wouldn't you get a CEL? The previous generation Civics are known to develop cracks in the exhausted manifold near the oxygen sensor. Don't know how different this generation is, but the initial symptoms were similar to what you describe.


I have been getting a CEL for catalyst efficiency P0420 but it only happens after it rains and would only come on about every 3 or 4 months after I cleared it.

Going to try citric acid this weekend on the cat to see if it cleans it up at all.