98 Civic Rattling Noise when pressed on Gas

| 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

"Me1" wrote: > On 28 Mar 2005 22:26:39 -0500, futuralogic > wrote: > > >Dear friends, > >

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