Possible problem with my Z?
 

Hey guys,

I havent posted here much, but Ive been lurking since March at least. I have ran into a few things with my Z that concern me (besides the paint) and wanted to see if you guys have any input or advice.

Lately, since it has gotten colder here in Tennessee, I have noticed that when I start my Z in the morning, the car will idle at about 1.5k rpms. Now this didnt concern me too much initially as I assumed that it was a feature in the car that would help it warm up quicker, however lately about 2-3 seconds after starting the car, there is a noise that is coming from the rear that sounds almost as if something is locking into place. I have tried to pinpoint exactly where the sound is coming from, but havent had the luck yet. At first, I thought it was a backfire, but I have been able to rule that out.

Now the second thing that concerns me is that after all of this has happened, I can smell something in the cabin. It smells almost like a gas/oil burning, but Ill be the first to admit that I dont know a huge amount about the internal workings of a car so I cant pinpoint that either.

Is this something that anyone else is experiencing or should I be concerned? The service shop at the dealer has been trying to play it off like its normal, but it just seems a little odd to me. I only smell this for the first minute or so of driving and then everything is back to normal. I also havent noticed a decrease in power.

Thanks in advance for your input.

Mine idles at 1.5K as well when its cold and its to help it warm up. I haven't noticed any strange nosies or smell though. It might just be just the exhaust you are smelling. I don't think its problem.

the 1.5k-ish cold start idle is VERY normal. (2nd post on this in 2 days)

as for the smell...maybe a varmint jumped up on top of your exhaust? ...

Idling with the garage door closed? :icon14:

wind direction changes in winter usually... (?)

someone farted.

At cold start the ECU will adjust ignition timing, fuel ration and I believe even cam timing to quickly bring the Cats up to operating temperature. (Cats don't function well when they are cold). This is also referred to as "Cat light off". So simply put, during cold start, part of the combustion process is still ongoing when the exhaust valves are opening. This results in hot exhaust gasses (to heat up the Cast), a different exhaust note and potentially a smell.

The past couple of days it's been snowing and nasty cold here in Chicago. There's also been a lot of rock salt on the streets which now coats the car. When I get in the car in the morning, I've heard a 'clunk' as I sit down in the car. Is this the sound you're talking about? I've had it with other cars before in similar conditions...the salt and grime makes the brakes or drive shaft stick. When you sit down or start the car in motion the first time, the shifting of the car frees it up.

Thanks to all of you guys for your input! (even the person who said someone farted, haha.)

Yes, I would describe the sound that I am hearing the same way.

Sounds as if maybe all of this is normal and I was just being paranoid, heh.

Well, now that you mention it....the past few days I've noticed a burning smell from the engine bay when I turn the car off. Just now I went to the gas station after a 20 min drive from work on the highway, turned the car off to fill up, and when I restarted the car there was a distinct, burning clutch-ish smell in the car. I've smelled the same thing when getting home and turning off the car over the past week.

Investigating further, it smells like it's coming from the back of the engine bay. The clutch is top on my differential but I'm no expert on this either. I have a 6MT and it seems to be shifting just fine, no grinding, easy gear changes...

Anyone have ideas?

(Will post this as a new thread with a more specific title to garner attention)