Question about revving an engine

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Hey, new member to these forums. I came across a thread in regards to the consequences for revving an engine and had a few questions. For starters, I have a 93 Mitsubishi Eclipse (automatic), bought from a private seller with a brand new tranny; I have owned the car for a good 3 or 4 months now. Now, I was just wondering if revving the engine while in park to about 5 or 6 rpm is bad for the tranny and/or the engine (no, not on a cold engine either). Also, is "manually shifting" a bad thing do to as well? Meaning, start off from a dead stop in "L" rev to around 3 or 4 rpm, shift to "2" rev to 3 or 4 rpm again, and finally shift to "D". I don't do these things often, considering my uncertainty of the consequences, so I figured I'd ask on here.

Thanks in advance.

posted by  FeaRx

i was wondering the same thing for the L to 2 then to D if its good or bad? :banghead:

posted by  mellowyellow4ly

Shifting manually can't hurt anything. It can actually be better for the trans if your higher gears are slipping. Keeping it from going into a higher gear and burning them out.

Running an engine in park doesn't hurt it, if you start to move the car in neutral (same thing as park but without the pin) it can hurt it. That is why you're not supposed to tow an automatic vehicle on its drive-wheels. The tranny isn't getting any oil pumped through it while it's in neutral. So in short to your question, no, it won't hurt the trans.

Reving the engine is bad for it no matter what the case. In theory you want the engine to stay at as low of RPM's as possible, that is what granny drivers cars last so much longer. But no, it won't instantly hurt your engine, it may just last 50k less than a babied one.

posted by  88GrandPrixSE

hmmm, well it's an automatic for a reason so why would you wanna do a stupid thing like that, just put it and D and go, yes you can manually shift and it works great for alot of things but why the need to rev it so high b4 shifting it up, that would deffinately be bad, if your manually shifting an automatic for i dunno maybe you want 2nd gear for a hill or sumthing , shift then go don't rev the bag off of it then shift that will cause alot of problems

posted by  BanffAutoSpa_ap

4 grand isn't a high, that's low when shifting generally. Because obviously you're manually shifting it for a reason.

posted by  88GrandPrixSE

well here is my take on it and if you want to see how well liked i am around here,just look at the one about torquing down the valve cover,anyhow,here is my point of view.
the car you are driving depending on the year,is a mitsubishi.they are famous for having design flaws.but at least consistent.the stealth ,and the 330 hp
twin turbo and the 2.0 talon turbo,all had some problems.first of all ,some engines have rev limiters,on an unloaded basis (gm v6)exceed 3000 rpm and it will cycle.the reason for that is with no load on the engine,it can have the same effect as trying to go really fast on a ten speed in first gear,once your legs go so fast,the inertia can go against,causing havoc.if you rev the engine really high and the car is MOVING ,it is also covering more DISTANCE,so by the time you go a certain amount of distance,the time duration is less.a granny might drive really slow but by the time there is mileage on it,the engine has twice the time on it .all new gm trucks have an hour meter in the dash,and you can tell if it is city or highway kms on it. your transmission is computer controlled.it has many sensors.
if you shift manually,you will tell it to shift harder,putting more strain on the drive components.that transmission is driver adaptable and the valve body controller varies the pressure via the info recieved as to rpm.if you drive it in "d" it will adapt to throttle input.if another person drives it lightly you will find for a period of time that the shift points will linger at too high an rpm.the main purpose for the 321 in the first place is for HILLS to use the engine as a brake,as in with a standard.the overdrives today have less than 1:1 ratio,and hence no drag.it will rocket down a grade and you will be on the brakes.if you are on a hill climbing and you see it hunting from 3 to OD ,put it in 3 or the torque converter can overheat.blown torque converters is the main defect in those transmissions.if it goes,the metal gets in everywhere.
in summary,drive it in D except for hills.in stop and go traffic 3 or d ,because the od will not kick in to 60 km,do not accelerate high rpm and dethrottle when it shifts,or it sees little vacuum and shifts WAY to hard. change the tranny fluid every 48000 km.have it pumped out and replaced .run ams oil or mobil 1 synthetic.,if you have the turbo,it is intercooled and you MUST change the oil religously.some of the earlier models had trouble with the tensioners in the engine,if you have a sporatic tick,usually around 150000 km,you need to change it .they are fun to drive,and as long as you do regular service it should last you.oh,and as far as the engine is concerned,there is a shutdown relay,7500 rpm,but i would not rev it past 3000 unloaded. you will notice that the pollution control on that engine does funny things to the idle because it is trying to dissipate the oxides produced if you rev it up to say 6000 and decellerate quickly. cheers...

posted by  the lobster

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