help: scatching noise!

palbuddy

Member
Whenever the rpm goes around 1500, noise would come into the driver's side. The noise is not the cricket sound when it idles. It sounds like two gears lightly scatching each other. It is doesn't intense, but it is really alarming, cuz it is a new problem. My car is 01 MP3 with merely 70 K miles, and I hope that it is just soemthing most cars would do as they get used. But it is not the clutch, I think. Even if I press the clutch down, the noise persists. No matter what you do, you can always hear it, idle, speeding up/down, clutch up/pressed, as long as it is 1500 rpm, no more no less, it would complain.

I opened the hood, and rev up the engine by hand, and I could barely hear anything weired. But if I sit in the car and press/release the gas, the noise is quite obvious.

It seems the culprit could be from under the car. Maybe the transmission. Here is my guess:

1. the gears got worn over the years and crumbles of metal mix with tranny oil. But I drained and filled the tranny oil only a year ago. And I used Castrol. The oil shouldn't have so much build-up.

2. Some parts are getting loose, and when the engine revs up, it would rattle.

3. welcome to Mazda's transmissioin.

Any experience/suggestion?
 
It might be an alternator bearing. My taurus makes a kind of whine at 1600 and sometimes 2200 rpm when cold. But like yours it's only at that rpm, doesn't matter if it's accel or decel. I just listen, and it hasn't gotten worse, so I'm leaving it for now.
 
This is what I found out yesterday:

CEL code P0421, meaning 'Warm Up Catalyst Efficiency Below Threshold (Bank 1)'.

Are these two related...

mgs_freak said:
It might be an alternator bearing. My taurus makes a kind of whine at 1600 and sometimes 2200 rpm when cold. But like yours it's only at that rpm, doesn't matter if it's accel or decel. I just listen, and it hasn't gotten worse, so I'm leaving it for now.
 
Can you pinpoint the noise from the driver's seat? The substrate inside your cat can become damaged/loose and rattle as well. Have you hit anything lately, like in the road? Big pot holes?
 
bring your car to the dealer and have the replace the cat under warranty before its too late!
 
My warranty expires, and it was 3 yr 50K mi warranty, and now it the 6 yr and my car has 70K on it. So I might have to replace it myself. My question is:1. is it difficulty to replace it yourself? Any estimate on the time it will take? 2. how about the parts? Icalled Kragen today and they told me that they have a part for $60, and that is the only one. It is a universal parts. Then some garage told me that they would charge $800 for it because of the parts. They said that $60 for the parts wouldn't work, because it is not OBD 2 compatible. They gave me a $800 quote for replacing it! Man, $800, apparently too high, and I don't trust them on it. So if the part is not OBD 2 compatible, can I pass the DMV smog test anyways?


Thanks a lot!!!

TheMAN said:
bring your car to the dealer and have the replace the cat under warranty before its too late!
 
what part are you trying to replace? what part did kragen quote you on? have you had it checked out or are you just guessing?
 
Keon1542 said:
what part are you trying to replace? ?
The catalyst converter.

Keon1542 said:
what part did kragen quote you on??
the catalyst converter.
Keon1542 said:
have you had it checked out or are you just guessing?

I got CEL code P0421, and it could be the cat or the o2 sensor, but I tested the sensor yesterday, and both were good.

So it must be the cat, and msg_freak and The_man made a good point. The kicking noising should be from the cat. I drove 1800 miles last week in 3 days, and the long trip might have failed the cat. My car is 01 MP3, with only 71K mi on it. It is surprising that the cat itself gives up so quickly.

For a quick fix, I think I should buy a MIL simulator from ebay ($10 maybe), and get rid of the code. But in the long run, I think I still need to replace the cat.

If I install a MIL simulator, can I pass the dmv smog check then?
 
palbuddy said:
My warranty expires, and it was 3 yr 50K mi warranty, and now it the 6 yr and my car has 70K on it. So I might have to replace it myself. My question is:1. is it difficulty to replace it yourself? Any estimate on the time it will take? 2. how about the parts? Icalled Kragen today and they told me that they have a part for $60, and that is the only one. It is a universal parts. Then some garage told me that they would charge $800 for it because of the parts. They said that $60 for the parts wouldn't work, because it is not OBD 2 compatible. They gave me a $800 quote for replacing it! Man, $800, apparently too high, and I don't trust them on it. So if the part is not OBD 2 compatible, can I pass the DMV smog test anyways?


Thanks a lot!!!

dude, READ YOUR WARRANTY HAND BOOK
catalytic converters are covered under the EMISSIONS WARRANTY, *not* the bumper to bumper warranty

I won't tell you how long and how many miles its covered under because you *need* to read the book
 
there is no way a catalytic convertor is only $60, that is the only reason i was asking...bet they quoted you for a O2 sensor
 
TheMAN said:
dude, READ YOUR WARRANTY HAND BOOK
catalytic converters are covered under the EMISSIONS WARRANTY, *not* the bumper to bumper warranty

I won't tell you how long and how many miles its covered under because you *need* to read the book

Yes, it still under warranty. Thank you so much!
 
Hey palbuddy, you definately want to get the car checked out before you start throwing money around for something you might not need. Long trips don't make your catalytic converter go bad. If it's your secondary cat making the noise, I wouldn't worry too much about it. The secondary is really more of a clean-up cat.

Regardless, neither of your quotes sound right. In our cars, you're not going to be able to use a "generic" cat, but it also shouldn't cost $800. I had a cat installed on my taurus, parts and labor cost $260.
 
Guys, thank y'all for your help!

The warranty on emission is 80 K mi/ 8 yr. I live in the Santa Cruz, CA area. And there is a local dealership named Marina motor company in Capitola, here is the web
www.marinamotorcompany.com

But the tech guys were a bit rude. I don't know how good they are, but when I called and ask about the warranty, the guy told me something really stupid. He insists that I bring the original warranty paperwork to them, otherwise they wouldn't do it for free. The most weired thing about what he said is that they couldn't find my warranty info by the VIN in their system!!! OK, I then dropped the talk and called Mazda customer service, and they confirmed on the warranty. I asked them to talk with that stupid dealership, and they got back to me and said the service manager said they could find the warranty, just bring it in, blah...

I don't really want to trust them, I don't know if I should, should I? It will cost $106 just to diagnose the CEL code. And my worry is that maybe they would tell me that it is not the cat's problem, so the warranty won't work, and even push me to replace unnecessary parts!

So, guys, what should I do to make sure that I wouldn't be screwed? I had an unpleasant experience with a Mazda dealership in Lansing, MI. That time I had a rough idle problem, and the engine rattled from time to time. I asked them to fix it, and they said it was the intake gasket, and the quote was $5 on parts and $400 on labor. Sh*t! I finally decide to probe the problem myself. And I got to know this forum and eventually found out the culprit was the EGR valve! Following the nice how-to post, I got it replaced and it cost me < $200 total.

I tested both oxygen sensors this week, and they both were good. I know that P0421 means 1. cat or 2. HO2 sensor or 3. spark plugs. So I am pretty confident it must be the cat, cuz I replaced the plugs 2 weeks ago.

But what if they would tell me, "hey, dude, it is the plugs, and you have to pay $150 for it plus $106 for diagnosis..."?? It could happen, right?

Another option is the dealership called Almaden Mazda in San Jose, and after I searched in this forum, I found many ppl talked bad about them.

So it must be very hard to find a real good dealership, good meaning honest.
 
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Normally they will not charge for diagnosis if they do the repairs. You could ask them just to do a diag, then report to you what they found before they start replacing/fixing stuff.
 
Just came back from the dealership, finally it is the cat. And they would replace it under warranty. There was another pending CEL code (P0030) "random misfire", and they said it was because of the ignition coils. What they told me was that the cat failed because of the ignition coils. I have ordered coils from rockauto.com, and don't want to spend big bucks at the dealership; the dealer's price is $104 a piece!!!

Thank you guys on this forum for your patience and advice. Good luck to y'all!
 

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