Civic making Beetle noises - is it safe?

June 19, 2012 7:47 AM

Our car – a 2003 Honda Civic DX stick-shift – has started to make a rattling/ticking/whirring noise when it accelerates. Can we still safely drive it?

The car has 190,000 km (118,000 mi) on it. It’s regularly serviced by the dealer, and just had new plugs in the last 2000 km. It’s just started to make a sound on accelerating which ranges from “putt-putt” to roughly the noise an old VW beetle made, depending on engine RPM. At steady speeds, it’s fine. Revving in neutral doesn’t make the noise either; it’s only accelerating under load. AC on or off doesn’t make any difference. There’s no check engine light on, or any unusual temperature/displays on the dash. The noise is loud enough to hear outside.

It’s had a new timing belt in the last 30,000 km. The only thing I know it needs work on in the front shocks (Honda dealer was proposing over $3k to replace ‘em; other local garages have quoted less than half that). I know I should get it looked at soon, but is this something we should stop all driving and go directly to the shop?

posted by scruss to Travel & Transportation (13 answers total)

Muffler?
posted by KokuRyu at 7:48 AM on June 19, 2012

Does the noise 'accelerate' in conjunction to your moving speed? Clicking noises of that kind can be axle U joints going bad. You'd replace the axle assembly, not the U-joint itself.
posted by chrisfromthelc at 7:52 AM on June 19, 2012

Best answer: It might be an exhaust leak somewhere, they have a very distinctive noise, and comparing it to an air-cooled VW makes some sort of sense. It's unlikely that you wouldn't hear it at all in neutral, although when my Subaru had a leak it was certainly much quieter in neutral.
posted by InsanePenguin at 7:57 AM on June 19, 2012

Response by poster: Don't think it's the muffler, though it could be near the manifold. It's definitely coming from the front.

Noise correlates with engine speed, not road speed.
posted by scruss at 7:59 AM on June 19, 2012

Manifold exhaust leak is possible, with acceleration pulling the manifold away from the engine/the exhaust apart slightly as the engine twists under load.

SHould have told me yesterday, Scruss, and driven over to Oakville and I'd have told you what it was. I'm not back in town until Friday now.

Can you record the noise or something? Does it sound like the noise could be air escaping or something of mass (ie a heat shield vibrating between two things). Generally you can sort of tell (especially with something of an engineering background) if it sounds like something light and tinny rattling rather than something heavy knocking. Heat shields kind of buzz and tick at times.

If you can't feel it at all (no physical echo of the noise with your feet against the bulkhead for instance) it may be something minor but it's hard to tell from the description. See if you can record it driving past you making the noise maybe? Or is it possible from within the car?
posted by Brockles at 8:12 AM on June 19, 2012

I'd drive with a window down until you know for sure it is not an exhaust problem. Otherwise you could be at risk for carbon monoxide poisoning if exhaust is venting into the cabin with no escape route.
posted by COD at 8:20 AM on June 19, 2012

Is this an engine ping? Does it rattle more the harder you accelerate?

Is this a misfire? Does the car accelerate more slowly than it used to?

Has your oil light blinked on?

All of the above could be minor or not.
posted by Midnight Skulker at 9:40 AM on June 19, 2012

Since you mentioned it only occurs under load (moving), my first guess is that a CV joint might be going bad (noise is typically more the rattle/clicking type than the VW putt putt type). Check for grease on the outside of he CV boot, which, if leaking a bit, might mean the CV is dry resulting in the clicking noise. From my Honda experience, a bad CV joint is more likely to leave you stranded somewhere if it fails than to be hazardous while driving but I'd still advise getting it checked out by a mechanic. I'd recommend an independent import shop or Honda specialist over a dealer any day.
posted by pappy at 11:49 AM on June 19, 2012

Response by poster: No oil lights or anything else blinking.

Didn't have any luck recording on a drive past or from inside the car, but with the bonnet open and a mic about 1 m from the engine block I got this on a static rev [mp3]. Pretty sure it's something exhaust related, 'cos under the bonnet there's an exhaust smell, and I don't think I've ever noticed that in a car before.
posted by scruss at 6:09 PM on June 19, 2012

It sounds like you may have an exhaust leak, especially if it smells of exhaust. It's hard to tell from the sound clip (very amused that is filed under 'music' by the way) but does the car rev normally? It kind of sounds like it has a bit of a misfire but without knowing how it is revving up it's hard to say.

It doesn't sound terminal and does sound much more like an exhaust manifold (or just after it) air leak than the initial description.

Do you think the car accelerates normally? If so, then I'd be confident it's exhaust.
posted by Brockles at 7:19 PM on June 19, 2012

I have something similar on a 96 civic that has been puzzling me for years (though not so much as to fix it). The car also has a slightly cracked manifold. I've never figured there was a causal relationship but Brockles' description makes sense. Maybe this part of the design on civics is a weak point?
posted by genug at 10:30 PM on June 19, 2012

Response by poster: Yes, it seems to accelerate fine, thanks.

(and where else would I file it but music?)
posted by scruss at 4:50 AM on June 20, 2012

That is almost certainly an exhaust leak.
posted by InsanePenguin at 5:53 AM on June 20, 2012