2003 Monte Carlo - traction system and weird noise

I begin by admitting the only things I know about cars are what I have misremembered hearing on Car Talk. Looking for some insight as it has seemed to stump the garage I brought it to and my dad, brother and boyfriend who are all pretty good with cars.

2003 Monte Carlo SS - about a year ago I started noticing a strange sound at low speeds (possible I just can’t hear it at higher speeds), especially when making turns but more recently on straight roads too and noticeably worse when the AC is on (in fact, when it first started, it seemed to only happen when making right turns with the AC on.) Didn’t have the money to fix it, was embarrassed about that so I made the ever-mature decision to ignore it.

The sound is hard to describe (and not helped by the fact that I am hard of hearing) but the descriptors that get the most agreement are: 1) it sounds like a coffee percolator and 2) it sounds like a small clawed animal is trying to escape the inner workings of my car and 3) sounds like the chain on a boat anchor as each link is knocking into the boat one by one as the anchor is being slowly pulled up. As I said, it used to be a more occasional sound, but it is constant now when i am not at highway speeds/accelerating - worst when the AC is on, but so long as I am not accelerating I have heard it at speeds up to 45mph on a straight, flat road. It sounds creaky and knocky - sometimes it feels like something wants to fly off the car or is flapping around under the hood/under the car just waiting for the chance to break off.

More recently, some dash lights came on - “traction off” “abs” and the warning light telling me to service the traction system. I opted NOT to ignore potential brake issues and took it to a local garage that my father and a close friend trust for both this and the noise. They called me to discuss the problems they found - they told me that a bearing had cut a wire in my traction system which was making the lights on my dash go on and that the sound was the honeycomb material in my catalytic converter being all torn up and knocking around inside so I had to replace it. I also gave them a go-ahead on a 100,000 mile service and oil change. They also called me back to say that my spark plugs had gotten stuck so instead of just swapping them, they had to do an additional repair on that - I had recalled a few times Click and Clack mentioning this is not the least common thing in the world so I didn’t blink and when I picked up the card I was happy to pay $1995.00 for a car that wouldn’t give me anxiety.

Only, that lack of anxiety lasted about 30 min.

I noticed the sound but (remember how much I know about cars …) thought that it was maybe some of the honeycomb whatever still working its way out of my exhaust system? But after briefly parking at home, I restarted it to run out to the store and the dash lights all came back on for my ABS/Traction. I called my brother who implied I was naive for believing I needed a new catalytic converter at all and believing them when they said it was causing the noise. When i got a hold of my dad, same reaction about how I should not have let them replace the catalytic converter and that there was no chance a bad one would have made that noise (he had heard the noise). My boyfriend was puzzled as to how the catalytic converter would make the noise he had also been hearing but was sweet enough to only wince when I told him how much it cost to replace it instead of acting like I should have known better than the mechanics whose expertise I was paying for.

The garage was very sweet about it - I brought it back over the next day and they told me the ABS/Traction/Warning lights were because a wire had simply come loose and that they had no idea what was causing the sound, but they would throw the car on a lift and lube the front end for me and as I drove and worked it through, the sound would go away! I skipped out of there again feeling warm and fuzzy.

That was exactly a week ago.

Yesterday the traction/abs/warning lights all came back on. The sound has not gotten any better and now that it is getting warm and I am using the AC, the sound is getting worse with the AC and its rattling/knocking constantly - it was slightly better when I picked it up the first time, but its just as bad as ever now and at no point has the sound ever gone away completely.

I need to absolutely take it back for the stupid traction issue, but I want to address the sound too since I paid a pretty penny to replace a catalytic converter which they assured me was causing it. Any ideas on what the sound might be? Suggestion as to things I can ask them to check?

I am feeling really stupid and naive and the idea of bothering the garage for the 3rd time about the same problems makes me feel like a jerk. I could really use a bit of insight - thanks in advance.

Why would you feel like a jerk? It is YOUR car and you paid good money to get it fixed to folks who supposedly knew HOW to fix it and it is NOT fixed. Stand up for yourself. Stop beating yourself up about it and if your dad and boyfriend knew more than the mechanics, THEY should have offered to fix it.

Rant over, if a bearing damaged the wire, did they replace the bearing? Or just the wire? And why not the bearing? A cat convertor can cause a rattle but not all the other stuff but a bad one WILL tell the car’s computer it is bad if it is broken up inside. It will turn on a Check Engine Light (little yellow glowing engine on the dash). If you did not have a Check Engine Light, I suspect the mechanics unnecessarily replaced the cat. Was this a muffler shop, by any chance?

Rotating things cause the noises you heard. That sounds like a wheel bearing or maybe a CV joint (drive-shaft part) going bad. Could also be bad engine mounts You gave the mechanics 2 tries to fix it, maybe you need to go somewhere else. A good independent shop.

Thanks Mustangman - I appreciate the pep talk and the advice. I guess I feel like a jerk because I am out of my element and want to be absolutely sure I am not being a ridiculous customer - your rant sunk that in!

Check engine light never came on … ugh … unnecessary Catalytic Converter. Awesome. Nah - not a muffler place - it was a Firestone garage. The bearing was replaced, not just the wire … but the wire coming loose a second time in a week after being brought back? Feeling paranoid about that!

Thanks for the suggestions and for helping with the thinking - was not sure if I should still be bringing it back to the 1st place to have them “make it right” or just slap down ye olde plastic somewhere else and hope for the best.

Interestingly, about 2 years ago the wheel bearings were replaced by this garage - this car used to be my dad’s spare (bought brand new for my mom and became a spare when she got a new car) and was sold to me for a pittance when my beloved Cavalier finally died so I actually do have a good history on this vehicle! LOL

Crossing my fingers its the cheaper fix of whatever you suggested - thanks for the ideas, I will be sure to mention them when I drop the car with a new mechanic!

Firestone does not have a good reputation. I would never use them. As Mustangman said, find a good Independent shop, not a chain.

The whole wire being cut by a bearing sounds totally bogus.


Thanks BillRussell!

(So Mustangman debunked the need for the catalytic converter and now you are casting doubt on the bearing story … I teased at the time I could have taken my boyfriend and myself to Hawaii instead of getting the car fixed … should have gone to Hawaii and left the car at the independent shop to be fixed while I was away! I have a horrifying feeling that it would have cost the same in the end and at least I would have a tan AND a working vehicle to show for it …)

Independent shop - I hear you both loud and clear! :slight_smile: There was a shop near work that I took my last car to and the mechanic who looked at it told me what it would cost to fix it and very gently and subtly conveyed I would be an idiot to fix it. No charge for checking it out, either - I was treated more than fair and they were helpful and kind. I had thought to bring it there, but the Firestone is a lot closer (easier to get rides to drop off pick up) and had worked on this car before so I thought I might do better there. Obviously not - I must have been insane to second guess myself and bring it anywhere but to the Independent shop that had been honest and fair before. Lesson learned, never to be repeated!

@CarolynM, Customers aren’t really supposed to know how to fix their cars, that’s why they are at the mechanics. right? Don’t feel dumb and don’t let them make you feel that way. The best customers describe everything the car is doing they think is wrong. The service writer, and hopefully the mechanic, too should have a dialog with the customer to determine the diagnosis.

I’ve seen know-it-all guys come into a shop and TELL the mechanic what to fix against advice and be upset THAT didn’t fix the problem! Who’s the dumb one there? If you insist the shop replace the wheel bearings, and they don’t agree, don’t be surprised the noise didn’t go away!

The big chain shops run on commission and generally don’t have good reputations for quality work. The indies will almost always beat them hands down for quality work. They may be a bit higher on price for individual repairs but they will save you in the long run.

I walked into our local Firestone store to get a tire fixed quite a while ago and the mansger who was behind the counter turned as white as a ghost.
Apparently I am a dead ringer for an investigator from our states Attorney generals office.