I now have 1,600 miles on my SSM sport auto and notice that the engine revs up to 2000 rpm on cold start up. (foot off the gas) All my other fuel injected cars started at equal or less than normal idle rpm when cold. I think these high rpms before oil gets to the bearings reduces engine life. Is this conventional wisdom out date? Thanks.

 

My GD3 holds steady at 1500 RPMs on a cold/first start and then slowly lowers as the engine gets up to normal operating temperature. My guess is that the ecu is set up to do that during cold temperatures and initial starts.

 

correct the colder it is the higher it revs
to a certain point that is.

 

k here's something i found http://money.cnn.com/galleries/2007/..._myths//3.html

and don't worry about the idle speed being higher, it's normal.

 

2000 seems fine if it's cold. If it was higher, then I'd be concerned. You're fine man.

 

Mine revs up around 2k now that it is colder in the mornings as well. I hate it, I can't shift at 2k anymore but hey what can you do? Ohio is cold!

 

Mine also revs up. It has been cool here in Wisconsin.

 

Mine does the same, I was worried at first. Good to see I'm not the only one. Anybody have a more detailed insight on why this happens?

 

this is anecdotal, but I read on another site (not honda) that higher revs during warm-up on fuel injected cars is to quickly heat the catalytic converter to the point of being effective. During warm-up cars spew hydrocarbons. They've increased idle speed hastening warm-up to decrease emissions. But it is reminiscent of the high speed idle on carbureted engines in the good old days.

 

Theres actually a few reasons for this.

1. Overcome greater internal friction when the engine is cold.
2. Fuel will turn back into a liquid instead of a mist when it hits the cold engine so more fuel is being dumped in to compensate.
3. And to heat up the catylitic converter because we're killing mother earth.

you should let your car warm up first before taking off. Especially in automatic trans cars because braking and stopping while in drive and the rpms still elevated is not good for the trans. M/T vehicles have it easier as we can continue to sit in neutral.

 

Oh please, let's not perpetuate this myth. Start it and drive (gently the first half mile or so). The days of having to warm up cars to keep them from stalling ended with fuel injection.

That said, if my windshield were covered with ice, I'd do as someone else suggested and start it, turn on the defroster, get out and scrape, drive off. No, wait: start, defrost, scrape, get in car, drive off.

 

Actually even if the car is VERY cold and you just started it once put into Drive it will lower it's RPM's to a normal idle rate. When put back in neutral if still cold it will increase the RPM's again. But while the car is in gear it will hold a normal idle rate. I usually go out and warm up the car but thats just because id rather sit in a warm car not worried about the engine warming up.

 

QFT

ten characters

 

um that's because you're putting a load on the engine, irrelevant here

 

i never said the engine would stall. obviously the revs will drop when you put it in drive, as stated by mike2100, you're putting a load on engine. Do you think sitting in drive with your foot on the brake and reving up the engine is good for the trans? well when its cold its doing this on its own, probably not enough to do any damage, but who knows. again, this is mainly for automatics.

I usually just start, defrost, scrape, get in , blow at my hands, sit on my hands, say holy crap its cold to myself, and then drive off.

 

just wanted to add one more thing. I'm not absolutely positive about i-vtec, but vtec does not work until the engine is up to temp and out of limp mode. But i'm pretty sure no one floors it leaving their driveways anyways.

 

The reason people warmed up their cars in the olden days (besides being warm inside), was to bring the engine to operating temperature providing easy vaporization of fuel. If the automatic choke wasn't in perfect adjustment, and later with low compression engines and smog controls it got worse, the thing would stall. Not once. A lot (see 1970s chrysler products).

Fuel injection makes this unnecessary. It meters the fuel correctly, all the time, at all temperatures, to provide a smooth running engine even when cold.

Car manufacturers started programming a higher idle speed on fuel injected cars to heat up the catalytic converter more quickly. This is one time (cold engines) where emissions are still bad.

Higher RPMs and an automatic transmission in drive while stopped will eventually overheat the transmission (the torque converter is a viscous fluid coupling that creates heat when the car is not moving) but you would have to do it for a long time at operating temperatures. This isn't a problem when the car is cold, and self correcting as you drive. It's not like a dry clutch that's rubbing all the time.

The same routine you practice for a manual (start, blow on hands, drive) is perfectly fine with an auto. Probably better as you don't have to worry about grabbing a cold stick.

 

I'm pretty sure a lot of dumbasses do that

 

My neighbor being one, at 7:30 A.M. with his loud straightpipe POS blazer thing.

Anyway I've noticed the same thing on my MT, but it usually goes away in less than 5 seconds and drops down to its normal idle speed.

 

if my 09 cold starts and goes to around 2200 right off the bat, is that normal? thanks! this forum is so informative.