What I thought was a rattle from the cat when the car is cold turns out to be coming from the engine bay. It seems to be coming from the just behind the valve cover in the area of the injectors or lower down. It stops after the car is warm. any thughts about what this might be?

 

Time for a valve adjustment?

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Flux &raquo;</TD></TR><TR><TD CLASS="quote">What I thought was a rattle from the cat when the car is cold turns out to be coming from the engine bay. It seems to be coming from the just behind the valve cover in the area of the injectors or lower down. It stops after the car is warm. any thughts about what this might be?</TD></TR></TABLE>

so is it knock or rattle? is it really cold in your area?

 

That is what I thought perhaps - but it actually sounds like a piece is loose or some part is vibrating against another part.... I did some hunting around in there and could not figure it out. It oes away when the engine is warmed up so maybe it is not a big deal...

 

Mine seems to do the same thing, and I know it needs a valve adjustment.
I just short shift @ 2500 rpm till it warms up a bit on cold mornings.
Doesn't seem to be much of an issue when its warmer out (45 F+).

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by zygspeed &raquo;</TD></TR><TR><TD CLASS="quote">Mine seems to do the same thing, and I know it needs a valve adjustment.
I just short shift @ 2500 rpm till it warms up a bit on cold mornings.
Doesn't seem to be much of an issue when its warmer out (45 F+).</TD></TR></TABLE>

Thanks, maybe I'll just get the valves adjusted when I'm in to get some tuning done... can't hurt. thanks.

 

every car i've seen sounds louder in cold.. at least for the first few seconds as oil gets through and maybe because valve clearance affected by temperature change??? - i'm not sure about hte last one

i'd suggest to try the folliwing, see if you can duplicated the problem by holding throttle at certain rpm.. try diffent rpm start with 1-1.5k then 1.5-2k.. even try up to 3k as diffetn rpm may result in diffent vibrations.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by vtec.dc2 &raquo;</TD></TR><TR><TD CLASS="quote">every car i've seen sounds louder in cold.. at least for the first few seconds as oil gets through and maybe because valve clearance affected by temperature change??? - i'm not sure about hte last one

i'd suggest to try the folliwing, see if you can duplicated the problem by holding throttle at certain rpm.. try diffent rpm start with 1-1.5k then 1.5-2k.. even try up to 3k as diffetn rpm may result in diffent vibrations.</TD></TR></TABLE>

It isn't that the car is louder - there is a distictive rattle and it continues until the car is good and warm.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Flux &raquo;</TD></TR><TR><TD CLASS="quote">

It isn't that the car is louder - there is a distictive rattle and it continues until the car is good and warm.</TD></TR></TABLE>

if its rattle, and goes away as the car warms up, it has to be rpm related.. car is at 1.5k rpm when its cold and then it goes down to .8k

try to duplicate it by holding throttle at certain rpms.. start with 1-1.5k rpm.. hopefully that will show where its coming from

 

Do you have an OEM header/heat shields on it?

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by .RJ &raquo;</TD></TR><TR><TD CLASS="quote">Do you have an OEM header/heat shields on it?</TD></TR></TABLE>

nope. I know it is difficult to diagnose over the net - thought maybe others had the same thing going on. I'll dig around further and see what I can find..

 

Might want to inspect your vtec bearings for play

 

My guess is its just due to the cold. My R sounds like a POS in the cold. It makes all types of funny noises upon startup, it rattles, the hatch glass sounds like its going to fall out and the rear end makes a moaning sound when I make sharp turns. Once warmed up the funny engine bay noises go away though. I'm guessing you have nothing to worry about, but it may be worth checking into.

-Larkin who needs to adjust his valves too