High revs at startup!?
#1
High revs at startup!?
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.
#2
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.
#4
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.
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.
Last edited by doctordoom; 10-20-2008 at 02:39 AM. Reason: because i didn't know what i was talking about
#9
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.
#10
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.
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.
#11
Theres actually a few reasons for this.
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.
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.
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.
#12
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.
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.
#13
ten characters
#15
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.
Last edited by doctor1foot; 12-10-2009 at 02:54 PM.
#16
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.
#17
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.
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.
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.
#19
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.
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.