RXJoey

I spoke about this in a previous thread but felt this one needed its own home.

To reiterate the issues, I had a feul line recall done and the egr valve replaced due to a check engine light, since then I have had many issues. This issue in particular is a noise that I can clearly hear as I decelerate below the 3k rpm band, and also while I am at idle, it clips in a out at ide, if I want to make the noise loud, I press the brakes softy a few times and the noise starts to wind and get louder. The faster I go, the higher my RPM's go, the faster the noise winds. At idle I can feel the vibration of the noise in the brake.

The dealership said it was the brake vacuum hose. If you open the hood this is the 5 inch hose that is closest to the window on the drivers side. If I hold the tube, the vibrations I feel from the tube are consistent with the sound I hear in the compartment. They replaced the tube, and the EXACT same sound is happening. I wonder if this issue has anything to do with the hesitation and bucking I get when shifting at 4krpm or lower. If i shift above 4k rpm everything seems to catch fine with no lag or bucking. Could this vacum hose be causing this? Anyone know of a fix? Is the dealership completely wrong about where this noise is coming from?

I am going nuts trying to figure this out, thanks for any experiences and/or input any of you have had with this. If you dont know what vacuum hose I am speaking of from my description, I will post a picture.

Thx

RXJoey

DaveW

There have been a couple of threads about this - the hard line vibrates against the firewall and makes this noise. A simple fix is to just put a piece of rubber hose or something else soft between the line and the firewall. I think there may have also been a few other solutions...

RXJoey

Thank you I will take a look, I hope I can resolve this because it is absolutely distracting.

Thx

RXJoey

I Found the following in the forums, it was written by ECH

Can any of you point me to the actual TSB article this is in reference to? I searched and cannot find it. Also, is there a place aside from Mazda Motor Sports that would carry these 2 items listed?

Thanks

the following text in quotes is what ECH wrote a few months back in a different thread.

"The TSB adds a rubber isolator to the mounting point that holds the brake booster line. You can't keep the valve from fluttering/ticking, but the isolator does a good job of removing the noise from the cabin. For $5-$15 and a few minuts, it is a good thing to do.

TSB 011/97.

F285-13-363 - Rubber Mounting - about $11 (a "stud") - this is the only part you have to order from Mazda
9994-00-600 - Flange Nut - about $2 - yes, for a single brass 10mm nut! A good place to save $2, if you don't mind a trip to the hardware store, or rummaging through that big bin of spare hardware you have.

Install (5 mins)
Need a 10mm socket, and crescent wrench (not sure of size)
------

there is a metal vacuum pipe that runs along the top of the firewall. It is held on with two stamped metal brackets. The passenger end bracket has the engine ground on it. Both ends have easy access. This is the metal tube that the brake booster line, with the shuttle valve in it, connects to.
1. Remove the 10mm bolt from the drivers side bracket - toss it, swallow it, or add it to the big bin of misc hardware you have. Er, don't actually swallow it.
2. Loosen the 10mm bolt on the passenger side.
3. Screw the rubber isolator stud into the firewall where the driver's side bolt came from.
4. place the driver's side bracket on the other end of the stud
5. secure with the flange nut.
6. tighten the passenger side bolt again.

done."