98 Civic Rattling Noise when pressed on Gas

Dear friends,

Before I am posing this question I read through all issues related to
noise and nothing exactly fits my case. I have a 98 Civic with 60,000
miles on it. This is my first issue with Civic. I have done regular
oil changes and maintenance so far.

One bad habit of mine, never heating the engine before starting to
drive in winters. I thought it was applicable to only old cars and did
not relaize my new car is getting old too :-( Of course I have
changed my habit since 2 weeks. 3 Weeks ago I started hearing a
rattling noise when I accelerated from start. When I took my foot off
the gas pedal it disappeared. It does not happen when I am driving at
constant speed but only when I press on gas - almost always. My wife
says the sound is in fact very metallic rattle to hear from outside.
I thought I was late on oil change but even I had that done it has
persisted.

Kindly advise me or give me hints. I want to be educated before I show
up at repair center. If you can recommend any repair centers I
appreciate that too. Thanks a lot in advance!

- Bob

 

<snip>

| One bad habit of mine, never heating the engine before starting to
| drive in winters. I thought it was applicable to only old cars and
| did not relaize my new car is getting old too :-(

OK, at the risk of starting a religious war, I would like to state that
there's absolutely nothing wrong with not warming up the car. The engine's
most stressful times are when it's too cold; therefore, getting it up to
nominal temperature quickly is imperative. The best way to achieve this is
to start driving it gently immediately after starting it, without flooring
it until it has reached nominal temperature. Excessive idling will only warm
up the engine very slowly, and therefore subject it to more stress than
actually starting to use it right away.

Plus, it's better on the environment.

But that's not what you asked...

|. 3 Weeks ago I started hearing a
| rattling noise when I accelerated from start. When I took my foot off
| the gas pedal it disappeared. It does not happen when I am driving at
| constant speed but only when I press on gas - almost always.

"Rattling" is a very loose term and it's hard to guess. However, if you
think it could match "pinging" or "knocking" (which does sound metallic),
then it could be that your engine is knocking. It usually happens under
load, and can have several reasons. Perhaps the two most common ones are bad
batch of gas (try the next higher octane rating at the next fillup, if it
goes away it's knocking for sure), or a timing that's too advanced. Did you
ever check/adjust the timing on the car?

Of course it might be some totally different rattling. Maybe others have
other suggestions...

 

Couldn't agree more.

Right you are. My first thought was that the noise could be from the
valves. Does the "rattle" vary with engine RPM? Is it more like a
regular ticking, or a random rattling? Does it disappear after the
engine heats up? What weight oil do you have in the engine? How cold is
it where you live?

My second thought is noise from the catalytic converter heat shield. As
you accelerate, the engine will move a tad in its mounts, and the
exhaust system will shift a bit too. Perhaps the heat shield is loose
and rattles under acceleration?

 

We're all on the same page there. And I'd hate to think of a 60K Honda being
old; my daughter's '93 Accord has over 210K now and I expect it to give her
a few more years of reliable service.

The heat shield also comes to my mind. Since the noise is described as a
"very metallic" rattle I doubt it is coming from inside the engine. I'm also
led away from things like exhaust leaks for the same reason. I can't think
of anything very bad that fits this description - just something loose and
rattling.

Mike

 

Hey futuralogic,

I think mike is right... I had the same from on my civic 98.. The rattle
comes from the heat shield under the car (near catalytic converter), usually
one of the hinges has broken off, very easy to fix and your local garage or
what I did: took it off!

Keep on driving!
Jason

 

My 1994 Civic has been doing that the last two winters, but only when
it's less than freezing temps. My Honda-only mechanic said that it's
normal for older civics, something about the valves being a little
loose and the oil not getting to them very quickly. He gives the same
advice as the others, drive it gently until it warms up.

Nate

 

Big thanks to Randolh and others who thought it was the heatshield.
yes, it was. Yesterday I took to MIDAS location and found that bolts
had been rusted and shield was loose. They put a clamp. It cost me
just $6. I am so glad it was not a big problem!

Bob