Ok, I've been noticing this problem for a week or so now and I don't have any idea what it could be. When I take the engine up to between 3-4k rpms there is like a rattling noise which goes away if i take it up past 4k... any ideas?

 

Sounds like it could be valve lash. Have you adjusted them lately?

The only other think I could think of would be a heat sheild somewhere.

Where is the rattle coming from? What does it sound like?

 

ill go drive and get a little vid. give me a bit.

 

My Del Sol does that right at 4300 - about 5500. I had a friend hold it at that rpm and stuck my head under the car and it turned out to be my cat's head shield.

 

Rattles that come and go at a certain specific RPM are usually exhaust-related. Check your heat shields.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Targa250R &raquo;</TD></TR><TR><TD CLASS="quote">Rattles that come and go at a certain specific RPM are usually exhaust-related. Check your heat shields.</TD></TR></TABLE>

Same thing was happening to me at that was the problem. Check your exhuast.

 

i was going to say heat shield also

 

rattles then goes away, def a heatshield somewhere... get under there and rip em all off