Funny NA Noises

jules · Postby **jules** » Tue May 09, 2006 3:47 pm

Ok, I'll have a stab.

\"Small Almost Fast Rattling Sound At 2K Revs In Every Gear\"
Perhaps loose header heatshield, or loose bracket or bolt somewhere.

\"Loud High Pitched Rattling Sound At 3K Revs In Every Gear\"
Almost certainly exhaust/header heatshields. Perhaps even the exhaust bracket that attaches to the gearbox bell housing.

\"Every Now And Then When I Start The Car There Is A Loud Grinding Sound\"
Starter motor dying, and not disengaging after startup.

How did I go???

Jules

JSE · Postby **JSE** » Tue May 09, 2006 3:51 pm

Does this sound in every gear happen at just under 2000rpm?
I have exactly the same problems and am also stumped as to what it is!?

Mine rattles just under 2000rpm - I am had a tinker with the hood up and squeezing the throttle and mine seems to be coming from inside the engine somewhere, not outside so I guess I can dismiss any loose bolts etc. Its a very almost rattling \"tinny\" noise.

My car also has a grinding sound every now and then (1 out of 12 times i start it). Sounds like the ignition is having a very spasticated time firing up.

I think they are both the same symptoms your car has initial_mx5...im stumped as to what they are. Post if you find out...

jules · Postby **jules** » Tue May 09, 2006 4:10 pm

I'd almost bet my house that sound is not coming from inside your engine.

There's a good trick you can sometimes use to track down noises.
Hold a screwdriver tip to the area the noise seems to be coming from, and put your ear up against the handle. Good for finding bad pulley bearings etc..

Jules

Andrew · Postby **Andrew** » Tue May 09, 2006 5:55 pm

Throw out bearing on the clutch :?:

kitkat · Postby **kitkat** » Tue May 09, 2006 7:00 pm

catalytic converter???

test that just give the cat a hit a litsen...

JSE · Postby **JSE** » Tue May 09, 2006 11:29 pm

Mine ain't the cat...its definately something around the block or rocker cover...will have more of a tinker and play on the weekend and look deeper into the mystery.

JBT · Postby **JBT** » Wed May 10, 2006 3:07 pm

Which end

JSE · Postby **JSE** » Wed May 10, 2006 5:05 pm

After having more of a play and tinker with it I have figured out that it actually is the heatshield around the exhaust system. Will be takin git off this weekend. Thanks for the help everyone

manga_blue · Postby **manga_blue** » Wed May 27, 2009 6:27 pm

The heatshields also defend the firewall, passenger floor and the area in front of the passenger footwell that holds the ECU.
If you just do street driving then removing the shields will make it a bit less comfy for the passenger, especially barefooted ones. If you give it a hard session on a hot track or on a dyno then you might fry the ECU and the wiring around there and under the passenger carpet.

Heaps of rattles come from the shields or other random bits of exhaust or drivetrain making contact with the body, either directly or through stuffed mounts or bushes.

Postby **mx52nv** » Wed May 27, 2009 7:52 pm

Have you tried:
Mazda Parts WA
(08) 9251 5000
42 Charles St
Bentley WA 6982 ?

Steampunk · Postby **Steampunk** » Wed May 27, 2009 7:53 pm

wreckers

jules · Postby **jules** » Thu May 28, 2009 10:18 am

Isn't that just a 10mm bolt with a captive washer? Look up a bolt supplier in your area and take it there. They should have heaps. Otherwise in a pinch grab a 10mm bolt and washer from Super Cheap and use that. Personally I think the manifold heatshield is overrated. I ran without one for years.

Jules

bruce · Postby **bruce** » Thu May 28, 2009 10:41 am

I'm with Jules regards the other noise being starter motor. Sharp grinding metal noise on start up (sounds like you're trying to crank the car when it's already running).