robfernando

OK - So it's 5 degrees F outside, windchill has it at -10 F. I crank for about 3 seconds, it starts fine! HOWEVER, when I take my foot off the clutch, the RPMs go nuts, kinda like a rough idle between 3000 RPM and 1500 RPM, it's like it goes to 3000, says ok, too fast and then reduces it to 1500 and goes, whoops, too slow!

Once I press the clutch back in, the engine is smooth again. Ultimately I had to keep my foot on the clutch for 2 mins before I could let it warm up normally.

Any ideas?

ZoomZoomH

iTrader: (1)

actually I think the 3000rpm jump is 'normal' for very cold startups

you should let the car warm up as it wants to.

jasmin

I have the same problem...anyone know the reason of that. I called the dealer and he said this is maybe a switch problem on the transmission....

RX8KRIS

I have the same problem... what oil are you all running in your trans?

jasmin

I don't know. I bought the car 5 month ago and I do not add trans oil.

RotaryP7

It's freaking cold now.. 53F..

In the morning my 8 said it was at 39F!

btw, this is freezing in Miami..

RX8KRIS

I put Redline Shockproof heavy gear oil in my trans and its a pretty thick oil so I figured the idle jumping on cold days came from the trans trying to sling the thicker really cold oil thru out the trans but I'm probably wrong.

RojoOcho

Mine does the RPM jump too. I think this is intentional. I just let it do it's thing before I drive.

secret8gent

haha, when i started up my car this morning (it was 6F out) i thought to myself:
I wonder if i'll see any 'cold startup' threads on the club.

and lo, I did.

it's 'normal' for an rx-8 as far as i know. let it do what it wants. Mine struggled for an extra 1/2 second or so (new battery but original starter '04) while starting but turned over and then revved itself to almost 4 before steadily dropping to 1.5k and holding there until it was warm enough to be movable.


two cents for you, 1 post for me.

Apostle

Every car i have had will have a high idle on cold mornings. once it warms up enough (not enough to get the heater working) it automatically drops to normal idle.

dont worry about it, as long as it doesnt stay that way or jump above 3k, you should be fine

Duke15

Mine cranks for about 5 seconds before actually starting, then jumps to 3 - 4K RPM. (approx 20 degrees F) I had the dealership look at it and they said I already have the heavy duty battery and it was normal - for whatever that is worth.

Leesha

It's -17C today...

I have an AT and it does the same thing until its warm. Kind of hesitates a bit then speeds up... Has a mind of its own I guess...

SilverStreak

I agree, you shouldn't worry. Mine has done the up to 4K then gradual decrease, it has also done the rev up and down between 1.5 to 3K. I haven't really identified a pattern to how or why but it always starts and once warmed up performs fine. It is possible that at extremely low temps the transmission neutral switch or the clutch switch may be sticking a little and causing the idle to "hunt" but that's purely theory on my part. As long as it starts and the idle settles in eventually all is right with the world.

enforcer

I will never complain when it gets down to 4C in Brisbane again!

RX8 dood

iTrader: (1)

Most newer cars do this....Its to get the fluids moving and everything warmed asap

2tone

iTrader: (3)

i concur. the *up-to-3k* appears to be normal for super cold weather. it freaked me out at first too. i do not however, have that erratic idle - it's just up to 2500 or so, then a gradual decrease to normal. i let it sit until at least at or below 1500 before i drive off.

RojoOcho

Warmed Up Renesis = Happy Renesis!

hagar852

This also has happened to me and I captured it on my phone. If I get a chance to get the video off of it I can post it.

Jeison

remind me to post a pic from my temp gauge when its -40C not including windchill.. those are fun days.. go outside and hope :p

04RX8man

Well i parked my 8 this winter but i remember last year that it did do that. and i noticed when you release the clutch the rpm's drop fast almost like it could stall.....seems normal to me never had any problems

TrochoidMagic

if you see temps that low in the area you live in, its wise to stick with the oil viscosity recommended for that environment. so its ok to use 5w20 and stick with it for that temp.

it should be normal. and don't be scared by it... as there are no ways to bypass this as our cars run on a drive-by-wire system without an iacv. there really is no way to alter it as the throttle now adjusts for warm-up idle speed.

let it do its job... if its not normal, then a cel will render it otherwise.

TrochoidMagic

btw, i see start-up idle near or above 2k. i've seen 50degrees or lower here on mornings. and i usually drive when the oil pressure sets around 50psi and when the water temp starts moving above 120...

then again, i have a gauge...

exarkun

Mine has done the same exact thing since I've had it (3 winters now.) I just always assumed it was normal.

However, it's been REALLY cold lately. (-12 F with no wind chill this morning)

Last Friday, after leaving work, I started it up, it did the normal rev thing till warm. However, once I pulled out of the parking lot, it flashed a CEL. I went to autozone and got the code pulled and it was this:

P0850 Neutral switch input circuit problem ON 2 CCM ´ (See DTC
P0850 )

I have no idea what that means...The next day though, the CEL went away by itself. But, yesterday, it was extremely cold again, and the code came back a little bit after starting it up. Anyone know what this code means? It seems to be related to the cold weather...

stuberncustoms

Engine code P0850 is a park/neutral switch input circuit error. I actually have that on right now. I have an appointment with the dealership to check it out because as of yesterday my 05 Shinka started idling erratically as previously stated and this code popped up. It was about 60 degrees when it happened so nothing to do with the cold. it pulsates from 1000 to about 2500 back and forth until i push in the clutch.

04RX8man

Mine does it also...I think it is normal I just slowly let out the clutch then the rpm's drop slowly then once the clutch is completely they climp up to abut 3k and finally fall to 1k when warmeed up enough to move...