intense_27

I did a search and couldn't come up with anything, so I don't know if this is a common issue. I don't really know if it is even an issue or not...

'05 MT, 125k km. P0076 code, not new when the issue started.

On very cold start ups of -20 Celcius and colder, the car starts up no problem, but it modulates the throttle between 1k-3k until it gets to a reasonable temperature and drops down to a reasonable idle. Another weird part to this...when I press the clutch pedal in, the rpm drops and stays down...release pedal, starts modulating again.

Thoughts?

CRAZ8

My 07 GT did this on a few occasions too. I don't know if its common though. My release bearing is going and I need to replace clutch.

kd7gab

Both '05's I've owned did the same during winter startups. I think it may have something to do with warming the CAT up. Temps here are not as extreme so I've never seen the behavior for anything other than short durations on cold mornings.

Posted From RX8Club.com Android App

Lateapexer

I was just about to post same issue.. thought there might be a sticky neutral switch or sensor. Maybe just normal cycling at -20?

Chrishoky

iTrader: (9)

This is 100% normal. The modulating throttle warms both the engine and the cat. The reason it returns to normal when you depress the clutch is so you can drive normally. When you next come to a stop, the throttle will modulate again until it reaches its warm threshold.

swoope

iTrader: (5)

this is the correct answer.

neutral position switch.

beers

intense_27

Thanks for the help guys, that was the answer I was hoping for

Hartness5265

Curious to how cold these cars can be and actually start, through the forums I see -20C very common. Can it go colder than that and not see flooding issues? -30C -40C? I know this seems like an extreme question but I live in the northern parts of the US and have been debating driving my 2010 RX8 in the winter. I realize this in the series I section of the forum, but was one of the more recently threads regarding cold starts I could find.


Thank you!

RIWWP

iTrader: (2)

At that kind of temp, it will start. I have started mine without significant trouble as low as -22F / -30C, so I suspect -40C is possible, though I really don't know how hard it will be.

Starting is the least of the problems though. That cold you will run into other problems

You will want a block heater to keep the block warmer if you can. Oil that cold won't be doing much at all for your engine, and it could take 5 minutes + of idling for the temp to really start getting into the acceptable range. Your bearing wear would be excessive.

The coldest day I started mine, the throttle pedal sensors had also frozen, sticking the ECU into a no-throttle limp mode that pegged the RPMs at 3,000. Only once the cabin thawed a bunch did I get throttle response back and the limp mode gone. You will still often have an idle hunt problem similar to a neutral switch idle hunt until the coolant temp warms up.

Heat cycling from -40C to +100C and back is going to be really really hard on parts and fluid. I would recommend an even more frequent rate of maintenance than normal.

Lateapexer

Does the RPM limiter vary with the temperature? Noticed that the colder the day the lower it is until the engine is warm. I've had no starting issues, but some driveability challenges in extreme cold ( power steering loss and all the warning lights on) which cease when the engine warms and or is restarted.

RIWWP

iTrader: (2)

The 2009-2011 rev limiter is 2 staged, based on coolant temp. Really cold starts don't add a 3rd stage.