mercerguy323

My civic has been idling a little rough/low lately. Usually after the car is warm and has been driven , and most noticeable when stopped at light, stop sign, in traffic......

Rough idle disappears when accessories are running. For instance, if I simply switch on the rear window defroster the rough idle disappears. Any ideas?

1,8L, 2008 Civic LX Sedan. 80,000 miles.

Thanks

ezone

Light, slightly annoying vibration? It's a 4 cylinder, they do vibrate. You can't adjust idle speed to compensate...

Does the vibration make something rattle? Locate the rattle and fix that so it's less annoying. (Hood often rattles against the latch)

If it's only a slight shaking without rattling, you might try a mount neutralization and an idle relearn, but don't hold your breath for much change.


.


OTOH,
Collapsed engine mount causing LOUD vibration?


Read this thread, post #11 has pictures of bad vs. good engine mount.
https://www.civicforums.com/forums/1...erse-gear.html

mercerguy323

Yup. Light, slightly annoying vibration. It's like someone turned down the idle a tick! Something as simple as turning on the rear defroster smooths it out. Gonna have to live with this one. I did read about the idle relearn. I haven't had the battery disconnected lately. Thanks...............again.

mercerguy323

Ok, so the rough idol is persisting, but I have another issue now. What's with this Civic anyway, did it just wait for that last payment (April) to start with issues? LOL

While using the front defroster, I noticed a gasoline odor. Usually strongest in the morning at first startup, and usually goes away after a little driving. I've smelled it several times now.

I don't smell gas when I open the hood and stick my nose in there. I don't think it happens when I turn on the AC or even just the fan in the car. (Tomorrow morning I am going to turn the AC on first thing to try duplicating the odor.)

I'm not sure if my idling issue and the gas odor are related, but they did show up as issues around the same time.

Fuel injectors? Exhaust leak? Vacuum line leak? Fuel line?

Can't I just have something fall off this car , so I can say "hey, this part fell off, I am going to put a new one on, and fix my issue?! LOL

I can see this coming. Another, "we couldn't find your problem or duplicate it, but here's your $400 bill, AND your car still smells like gas!"

Thanks in advance!

ezone

If it smells like raw fuel (not exhaust), you're probably gonna have to catch it in the act of leaking in order to find it. Stop and open the hood as soon as you start smelling it, before it quits.

Usually whatever gasoline seeped out that caused the smell will evaporate and leave almost no evidence to see. As soon as you don't smell it anymore is when it's evaporated away.

It's probably going to be in the engine compartment area...Quick connector fittings on the fuel line from firewall to engine, or injector seals. I'd probably suspect the line first.

mercerguy323

Thanks.
It's beyond me to fix/find it in all probability. I'm having it checked by a local garage Tuesday so, I guess they get first crack at it. I spoke with them about possibilities already. They mentioned injectors. Also said they aren't that hard to get to. Gonna test it when I get in. Quick connector fittings? Let you know what their guess is. LOL

ezone

Figure out a scenario where you consistently smell fuel, such as let it sit overnight and then run it in the AM with the fan on vent and fresh air.

Give the shop that scenario in writing so they have a better chance of duplicating the problem on the first try.

If you have to drop it off in the evening so they can check it the next morning, explain it, arrange it, and do it.

mercerguy323

I have an appointment with Honda for them to look at it. I did have a mechanic look at/smell it, but he found nothing visible. He mentioned the Evap Canister? as a possibility.

The odor is present not only when using the defroster, but also when using the upper vents for anything. Fresh air and the AC do the same thing.

I did notice that it does it if the vehicle is shut off, and sits for a little while, maybe 2-3 hours. So, although the overnight sitting gives off the strongest odor, it's present after a shorter period also.

My appointment is for 2 Saturdays from now, and I will be dropping it off the night before. This way, they have it first thing. I plan to give them as much info as possible when I drop it off. Bets on them telling me they couldn't find anything? LOL

ezone

I would expect EVAP leakage related codes if this were the case. The canister is below the back seat area under the car though, so that shouldn't be coming through the vents. Sure seems that if it is this consistent you should be able to open the hood and smell it also.Maybe the car should sit inside their shop overnight so there isn't any wind when they start it up.

mercerguy323

Ok. Just following up on my previous post. I read at another forum about a person who determined it was 2 loose spark plugs that caused his gasoline odor. Then the light went on. I had taken the first plug out a few weeks ago to check it's condition. I checked the plug again today, and found that it wasn't snug. It had about a quarter turn left! I also noticed that the plastic coil had a lot of brown film on it. It wiped off easily but it was definitely fouled. I took the car for a ride after tightening the plug and reinstalling the coil, and it seems to not only run better, but the idle seems to be back where it should be. Come to think of it, my car was jumping into passing gear while using the cruise control and going up a small incline. Maybe plug related too.

Do you suppose I created my own gasoline odor by not torqueing the plug correctly?

Gonna check the odor tomorrow morning, and then again in a couple days, but I have my fingers crossed!

ezone

Loose plug to me doesn't cause raw gas odor, it causes raw exhaust odor....maybe along with some noises. To me there's a big difference between the smells.


But if that solves your issue, that's great!

mercerguy323

I sure hope so. It aint over yet. I bought new tires today and they vibrate at high speeds! Around 66 the vibration starts. It never ends! Going back there tomorrow. Ugh

mercerguy323

Update. Gasoline odor persists as does rough idle, extended startup time. Could it be a misbehaving coil? Want to run a coil test. Have seen a test where you can start the car, remove the clip on one coil at a time and if the RPMs drop, that coil is functioning properly. If a clip is removed on a coil and there is no RPM change, that coil isn't functioning properly and needs replacement. Does this test sound right and would a code be thrown or the engine light come on once I unplugged the clip? I want to try this test as it seems simple enough but I don't want to set off codes or have any lights come on and have to take it to a garage just to reset the codes or turn the light off.

I've also been told that a faulty coil would send a code and cause the service light to come on so, it must not be a faulty coil causing my gasoline/idle/long startup problem. I've also read that a faulty coil doesn't always send a code. Any ideas? Thanks.

ezone

IF a coil completely failed, you'd have the check engine light on and misfire code(s).
If you start unplugging stuff with it running, that should set codes in the computer that will need erased.

Is this a raw gasoline smell? (fresh from the gas station pump)
Or a raw exhaust smell? (old lawnmower smell)


Recheck spark plugs, were they torqued properly or were they installed as loose as the last ones?