Is it safe for a cold car engine to be warmed up quickly by reving it up at a high revolution?
This question is posed to EXPERT car mechanics only please. We had an ol' 77 Honda civic clunker that my spouse would put on high choke and rev it up at high speed to warm up the cold engine...Now we have a '97 Ford escort that has some digital chips in the engine..the engine was replaced once already because I suspect that the warm up process my spouse uses wore it out real quick but he continues to do the same thing daily....My spouse will only listen to words of wisdom from someone of expertise in this matter...any suggestions?
Public Comments
- Cars only need 30 seconds of warm up, and NOT at high revs.
- it you want to blow it up then go ahead
- I'm not a professional tech... But it's common sense high RPMs aren't good for an engine, especially cold (oil doesn't flow well cold). And rapidly heating engine parts while much of the coolant and oil is still cold is also not good. Can easily cause warping of parts. (Think hot fry pan / cold water). Make him stop!!!
- It all depends on the viscosity of the oil. If it were very cold, and the oil were thick, it could cause problems. The best thing is to allow the engine enought time to reach operating temerature, generally 180 Degree's F. Hope this helps
- I am the EXPERT MECHANIC you speak of and I must inform you, DO NOT listen to these people you will break your car. Start the car, let it sit for 10 seconds, then PEDAL TO THEM METAL! ALL THE WAY, for 10 minutes, then throw it into drive, go 5 feet forward, throw it in reverse go 5 feet back. Then REV FULL RPMS again for 20 seconds then you're ready to go
- NO WHAT EVER YOU DO IT IS VERY BAD FOR YOU TO REV THE ENGINE TO WARM IT UP. AND ON THE NEWER MODELS YOU RISK BLOWING THE COMPUTER....
- A motor is made to run at a certian temp. At this temp all the parts fit right (metals expand and shrink at different rates). The pistons to say may have a little slop at cold temps and then expand to the best fit at the operating temp. You also need to let it idle a little to get oil up to the top of the motor especially when not ran in awhile although the oiling systems are getting better with newer model cars. If the oil does not get to the bearings and rings and such before you are over revving the motor they are wearing bad. The colder the worse it is. Depends on the car and the weather to how long it should idle to warm up.
- It is not good to rev a cold engine. The engine oil has not had a chance to warm and circulate well through the engine, before he is gunning the accelerator. At startup the bearing surfaces are pretty dry, having drained all oil back to the cranckcase with the engine off. Tell your spouse the best way to warm up an engine, is to put the thing in drive and head on your way after starting. He isn't sitting at the starting line of the Indy 500, so a normal idle will be best.
- Your husband was somewhat correct when revving the 77 Honda Civic, but that's only because it's a carburated engine. Since the 97 Ford Escort is an E-FI vehicle (Electornic-fuel injected), there is no need for the high rev's. The ECU (Electronic Control Unit) in the vehicle controls the amount of rev's during cold start up and will eventually change again once at NOT (Normal Operating temparature). I can't associate the high rev's for the cause for the replacement engine but I would assume that his already poor practices on warm up attribute further towards his driving habits. In addition, a 1997 Ford Escort is a pretty unreliable vehicle. Actually in 1997, any Ford is pretty unreliable, up until recently that is. They've recently started going towards Japanese technology and have since improved.
- I can tell you that it is not good on them. You take a cold metal and heat it fast will warp it. Same in a car motor, if you heat a cold motor fast and under stress with oil that is cold and thick it takes it toll on it over time. It will wear the crank bearings and cam bearings out, if it has alumina it will wear twice as fast as well as shorting the life of gaskets on the motor.I do not recommend doing it.
- Reving up a cold engine can be very damaging.When an engine sits over night,the lubricating oil has drained off the moving parts and down into the oil pan.This means that the first few seconds of operation that engine has no lubrication,not until the oil pump sucks up that oil and begins pumping it to various moving parts.So if you rev a cold engine the wear on moving parts is tremendous and it does not make the engine warm up any faster.The best idea is to begin driving right away,but keeping your speed under 30 mph for the first 10 minutes of driving.This will save gas and money for a new engine.
- Yeah, I have a son inlaw that thinks it's cool to rev the engine on start up. He's cold blooded and stupid. Those Hondas can take some abuse, but what they don't realize is little by little the engine is losing compression. Let the oil pressure build up, if it's cold outside more reason to just turn the car on, no gas ... let the computer adjust the idle. And when all the Honda(s) are in the junkyard, your lil Ford will still be (F)irst (O)n (R)ace (D)ay live long
- You do not Rev a cold motor the new vehicle just start and go don't wait till its warm it will get warmer faster if driven idling is not good for the motor either just or by the time you get to the free way the motor is ready for that speed , a cold engine wears out faster that a warm engine this is fact, use 5w30 or 10 w30 motor oil and do not Rev the motor this is the main reason the rev limiter is there to protect the motor, some vehicle that don't run right to begining with if you must rev it before you take off you have other related engine problems like the choke is inadequate , all vehicle to day are computer controlled fuel injection and the computer will not allow old thoughts to be applied to the vehicle , start and go fact, keep you oil and oil filter changed at regular seculed interval's and it will last for 100 of thousands of miles, providing you not revving it cold this is where 95% of all engine wear is done when the motor is started cold , than if you drove to L.A. to Vegas and back more wear is done when you start the vehicle, so keep the rev's down if this was true the MFG would have the motor reving when it cold , see what Iam saying, good question
- You don't rev any car when it's cold espcially because of the oil not getting in the oil passes fast enough to protect it (espcially with a used engine that might or might not have been taken care of and have gunk blocking those oil passeges. Ford Escort has a stategy to warm up the engine at 1500 and bring it down to idle for emissions pretty quick. It's supposed to hit 130 degrees F in a set amount of time. Actually a car now a days is supposed to be warmed up letting it idle down by itself and then driving it normally (not reving high speed) for a period of time to warm up.. I find a max of about 1500 RPM is best at warm up, as I have to warm up engines pretty quick sometimes and bringing them up to 1500 RPM for about a minute or two seems to do the job without throwing a rod... but I rev it up to that AFTER about 30 seconds to let the oil flow first
- ABSOLUTELY NOT!!!! There's not enough oil circulating through the engine at start up to properly coat the camshafts, piston walls, and the like. This can lead to scoring of the cylinder walls, engine siezing, and WAY shorter life of the engine. It doesn't matter what kind of car you drive, it's just bad for your engine. However, if you've got the spare 2000-4000 dollars to replace an engine every 60,000 miles, then go right ahead.
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