Rough Idle
 

Hello community,

I noticed this morning when I started up my 2004 Rx-8 with 28,500 miles, that the car was idling very rough. To better describe this situation, the tach needle would bounce between 2,000 rpms and 1,000 rpms every few seconds. At first I thought well maybe I just need to let the car warm up, no dice.

It also turns out that the car will only have this rough idle when i am stopped and the car is in neutral. If i put my foot down on the clutch, the idle goes back down to the normal 1,000 rpm. Anyone every heard of this before? I am a little worried because it seems rough idles are associated with needing a new engine. :sweatdrop

Thanks in advance,
Nxt

Sounds like a bad neutral switch

^+1 sounds like it's 'hunting' for idle. Neutral safety switch may need to be replaced. Doubtful you need an engine.

I just searched the site for the neutral switch issues and found this...

"a bad switch by itself will cause a hunting idle from 900 to 1300 that goes away when you press in the clutch.."

Sounds about right.

Anyone know how much replacing a "Neutral safety switch" would run or will the warranty cover this?

Thanks for the info Jon & bose.

it wouldn't be to labor intensive, doing it yourself would be pretty easy as long as you have some mechanical experience. I would call the deal where you got it and see what they are willing to do.

Just wanted to write an update for anyone curious:


So I took the car over to the closest dealer only a few miles away from my work. Turned out to be good timing because the check engine light came on while i was about halfway there. Anyway, I pull into the dealership and describe the problems I'm having with the car to the mechanic. I tell him that it was been suggested it maybe the "neutral switch" that's bad. He said it sounded like something else but I'd have to pay $98 to find out. I said fine, and was told to go sit down in the waiting room.

45 mins later the mechanic comes to find me and lets me know the good/bad news. He said the bad news "it was the neutral switch", and since I told him before hand that's what he should check. The good news he gave me half off the inspection price. *sweet* He told me that the "neutral switch" will cost about $90 with $100 for install. He also told me my motor mounts were going bad but had to check with my warranty to see if it was covered. I'm a little shocked the mounts are going bad after 29,000 miles, but whatever. The mechanic also told me he didn't see the rpms "hunting" for neutral. Well then how is the "neutral chip switch" bad?

I head out to my car to see for myself, and sure enough,the car starts up, no check engine light or rpm's hunting for neutral. I think maybe when the mechanic reset my ECU, that's all that was needed. Really though, if the "neutral switch" is bad, then shouldn't it stay bad until replaced? As of now I have to wait for the parts to come into stock before I can do any replacements. This goes for both the chip and motor mounts. A little odd I must say.....:squint: