jaesun

Whenever I drive my car around, and I get to a light, and stop, the car tends to have a rough idle. It feels like the car/engine/steering wheel shakes. And it seems that only the driver feels it. I have other people in the car, and they do not feel it they say. But when they drive it, they will notice it. So it is not rough enough to really feel it, but as the driver, it starts to get annoying after all this time.

It *usually* only happens when the car has warmed up, so it is not when the engine is cold. Also, if I slightly hit the accelerator pedal, it goes away (keep foot on break, and just slightly hit the acc pedal, the vibration goes away, or if I put in neutral and hit the accelerator pedal, same thing, the vibration goes away). This happens in gear, neutral, or in park (haven't checked in reverse).

I have taken it to the dealer, and they replaced the engine mounts, but that didn't fix it. They told me to put better gas in it (I just fill up at Costco), but even with Chevron premium, made no difference. I had my dad check it out, and he said it might be a timing issue (not sure if he meant belt or maybe something with the ECU or whatever?) or maybe I should check spark plugs.

Any other ideas what it might be? I won't have a chance to take it in to the dealer till next week. But hoping to get some ideas on what it might be.

Edit: 2009 Honda Civic LX-S, Auto, 4dr

KandabashiDevil

More info on "rough idle".

What is the RPM at when it starts to happen?
How low does it go?
Does the car make a noise?

motegicivic

Are you the original owner? if so did it ever idle smooth?

Any CELS?

What is the mileage?

jaesun

It only happens when it idles below 700RPM. So after the engine is warm, it idles around 600-650RPM, and it vibrates (can really feel it in the steering wheel and the center armrest, and the seat). If the car is warm and I turn on the AC, the vibration goes away usually (higher RPMs)

There is no noise associated with it, except the seatbelt fastener (near the center armrest) when it vibrates, the spring inside the seatbelt thing vibrates.

but really, it just vibrates, even more than I would expect. The car doesn't really idle at different RPMs. Usually when its cold, car idles at 700-800 RPM. After the engine gets warm, it'll drop to idle around 600 RPM.

moteg, I am the 2nd owner (bought the car 14 months ago and the car was bought in Nov 2008), and I started noticing this for the past 6 months. I took it to the dealer then, but they replaced the engine mounts, but did nothing to fix. So for the past 6 months, I been trying to ignore it as annoying as it is. But I figure with my certified warranty set to expire this nov, maybe try and get it fixed again, so started documenting when the vibration happens. I only noticed it in the past 6 months because when first got the car, my then wife drove the car. We since split up and I got the car.

the car has 39,000 miles. No CELs, I've done regular oil changes (at 15-25% oil life according to gauge), I don't drive it hard.

I know 4-cyls are supposed to have a vibration to the car, and I was told the Honda doesn't have a balance shaft ? but this vibration seems out of the norm. I had a 2k civic that wasn't like this, the car I had before this was a Hyundai, and it didn't vibrate like this either. I am going to try and see if I can test out another 09-ish civic and see if it has the same vibration. (maybe this is normal?)

motegicivic

When is the last time you did a basic tune up, plugs, maybe fuel filter.

I am not sure if you can with the newer civics can adjust the idle speed, but sounds like yours can go up a bit.

jaesun

I haven't done a tuneup. I have my oil changes done at the honda dealer, and they haven't given me any recommendations the last 2 times I went, except to change the air filter which I didn't bother doing.

I thought about changing the spark plugs just to see if that was the case (I thought spark plugs were changed every 60k miles or so depending on the plugs?), but I might just try that and see how it goes. Haven't changed fuel filter though.

motegicivic

Check to see how dirty the air filter is, they are pretty cheap at walmart or parts stores, I would replace it.

I would pull the plugs and see if there is any carbon build up or might be running too lean. Typically the plug change interval is pretty long on these cars but in your case I would just change them out.

Also, thrown in some chevron techron fuel cleaner in the tank, can't hurt.

jaesun

does the air filter make a difference?

oh, I should have been more specific..it was the AC/cabin air filter, not the air filter in the engine.

I will go and change the plugs and do the other stuff while I am at it today. maybe that makes a difference

motegicivic

Air filter can make a little difference, go check it should be easy and like I said they are pretty cheap from the parts store not the dealer, I would just do it.

jaesun

is there a specific spark plug i am to get? I went to autozone, gave them my car info, and they gave me Bosch plugs ( http://www.autozone.com/autozone/par...er=874695_0_0_ )

But after replacing the plugs, I hear a slight hissing noise (don't hear it inside the car, but I hear it when I am at the engine with the hood up) that i *think* wasn't there before. Read somewhere else I am supposed to only get NGK's ? May not be a hissing noise, but it's coming from the alternator i think. May be the alternator just spinning around ? (it sounds like its rubbing against something as it spins).

Brendon17370

i agree with motecivic maybe it just needs some more air in the system

ChrisRondon

After idling roughly does it shut off sometimes? I had this problem with my old accord a few years back where I would have to lighhtly keep my foot on the gas or it would idle really rough and I was told a few times it was IAC valve

90sbaby

I'm a tech at a Honda dealership in SC And I've had to fix a few 06 up civics with the same problem you're experiencing. What we found was that doing the ckp learn procedure and idle learn procedure after resetting the PCM usually will fix the vibration. Hope that helps

motegicivic

Bosch are not the best, you should of read the owner's manual and got the plugs from there.

You will hear noises if you listen under hood, not atypical I would not worry about it.

By the way I hope you did not go crazy tightening the plugs. With these plugs did it help? How did the other plugs look?

Did you replace the air filter like I said to?

motegicivic

do you have the instructions for the relearn?

90sbaby

Not really instructions unless you have access to an mvci or to Honda diagnostic system

motegicivic

Is there a TSB for it, maybe he can go back to Honda and have them do it for his car since he is still under warranty.