[urq] Rattle at higher rpm

[fdekat]

> Message: 3
> Date: Mon, 17 Sep 2007 10:38:57 -0600
> From: "Brandon Rogers" <brogers at terrix.com>
> Subject: [urq] Rattle at higher rpm
> To: "'Urq list'" <urq at audifans.com>
> Message-ID: <007201c7f949$44e0f1f0$2c01a8c0 at BCROGERS>
> Content-Type: text/plain;	charset="us-ascii"
> 
> So this is not a fair question (an I kinda know the answer - in that I
> know I just need to get under there and listen with somebody helping me
> on the throttle) but I'm going to throw it out there anyway...
>  
> For years I've had this annoying, fairly loud rattle - like a loose bolt
> or something, when I'm driving and the motor revs to about 4000+ and I
> shift.  This rattle has survived a motor swap and a cat swap.  It's
> definitely metal on metal and goes away as revs fall.  And it does not
> happen until the engine is warm/hot.  I'm thinking I need to get the
> engine hot, put the car up on ramps and carefull crawl under there (a
> little bit) and have somebody rev the motor.  Any other thoughts???
> Obvious places to look for something loose?  Maybe an odd bolt on the
> tranny?  Any BTDT?
>  
> TIA-
>  
> Brandon
> '84 ur

I too had a similar noise/problem (but temperature didn't matter). The noise
was really annoying, and really made the car feel 'wrong' when revving.

I couldn't find the problem until I pulled the head off to fix a blown head
gasket.

Seems as thought the starter heat shield had partially rotted away, and as
reves rose, it must have vibrated more. When I had the head off, I repaired
the heat shield, and after the motor seemd WAY smoother when revved up. I
never realized that was what was causing the problem, until I tried out the
car after the repairs. A 'bonus fix' as it were!

Could be some slack in the bolts the hold the downpipe to the exhaust/cat
too, I suppose...

=Frank=