RPM = number of Revolutions Per Minute. Most commonly an acronym for engine crankshaft speed.

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dirt bike low rpm lugging

I have a 84 Honda XL350R. I know redlining a dirt bike is not good, but what about lugging in a high gear? When I say lugging I mean lugging.(no throttle whatsoever, can say the 4 stroke cycle suck,...
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1answer
2k views

Clearing a P0507 on a Dodge Stratus

My 06 Dodge Stratus (4 cylender) is showing a P0507 off of the Torque app. My idle is sitting at near 1100 rpm versus the standard 800. I read up on the code and started looking for a vaccum leak ...
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42 views

Idle RPM is not setting properly sometimes

I have an Apache RTR 180 (Carbureted) Sometimes, when I downshift, and when shifting down to 1st gear (to stand still), the RPM shows somewhere around 2000. The normal idle is around 1200 - 1400 RPM. ...
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127 views

Short shifting after full throttle

Other than normal wear and tear, are there any detrimental effects or added harm done to the engine by going full throttle in 1st and/or 2nd gear, then shifting up well before redline (say 4k rpm on a ...
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2answers
50 views

Torque reduces gradually after certain RPM

I just know the plain definition of the Torque. Torque: Definied as the force applied to the object to rotate on its axis The torque will be increased only upto a certain RPM and it will gradually ...
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3k views

RPM fluctuation when maintaining speed in high gear

I recently got an oil change on my 2008 Audi A4 Quattro. Now I notice that when I am cruising in 3rd, 4th, or 5th gear (but not 6th), and I am at about 1200 RPM, the tachometer is not stable. The ...
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228 views

What mechanical revolution is measured in “RPM”?

I do realize that it stands for revolutions per minute, but what are the revolving pieces that are measured? Assuming it is the crankshaft, is RPM calculated by the crank shaft sensor, or by some ...
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37 views

High acceleration and dieing when brake is pressed

I have a 2003 Ford Taurus its been good only needed a new starter and new brakes besides the standard changes in the 6-7 yrs since i got it. Then 7 Jan 2016 hit. Since then it has been in the shop 5 ...
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4answers
99 views

How fast is one RPM on average?

I know this depends on a lot of factors but I heard a revolution can happen in 0.02 second is this the case? I can't even stop my stop watch that fast?
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4answers
297 views

Can 100% calculated load be reached in neutral?

While searching for information about how is engine load calculated I came across this question which contains an equation for the ECU load calculations. As I understand it under fixed atmospheric ...
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3answers
6k views

Why does diesel engine have redline much lower than petrol engine redline?

why do diesel cars redline at around 4500 rpm whereas petrol ones around 6500 -8000 rpm? Does this have something to do with the compression ratio?
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4answers
31k views

Engine power specification at different rpm?

Car companies advertise power of an engine at different rpms. Car 1: 80 PS at 6000 rpm Car 2: 85 PS at 6500 rpm What does the power at different rpm mean? Does it mean Car 1 has better power than ...
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0answers
121 views

2012 KTM Duke 200 - Low acceleration in low rpm [on hold]

Recently my bike (KTM Duke 200) is suffocating to deliver enough power between 2000-3000 RPM. I took the bike to a service station and they told me that its an engine problem, low compression and ...
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1answer
49 views

No Damage/ top fuel economy rpm shift point

I am driving my Brother's 2002 4.0L gas ford ranger truck 5 speed manual transmission. What RPM should I shift at for best fuel economy. Also what RPM should I not let the truck go below while driving ...
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2answers
528 views

cause of Rough / fluctuating RPMs in low RPMs

It's not dying (hasn't yet) but when the car is idling or in low RPMs the car (Mazda Protege 5 2002) is fluctuating in RPMs. Also, the last start was rough. I've had issues with air intake before ...
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1answer
36 views

2004 Honda Civic ex rpm spike and lose acceleration.

I have a 2004 Honda Civic. Sometimes when pushing on the gas at a slow pace around town the rpm jump up and it's difficult to accelerate. Once doing 60 it doesn't appear to do it. Does the ...
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2answers
313 views

Optimal RPM range for manual transmission

Are there optimal RPM ranges for different vehicles? I've been told it's better for the engine to drive at slightly higher RPMs (e.g. 2500-3000 for my Tacoma) than low (1000-1500). I understand a ...
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1answer
139 views

How do I know if car ECU has a REV Limiter?

My car is fairly new and not that well documented online (it's a new model from late 2015) For safety, how do I know if my car has a REV-limiter without testing it and letting it go up the red line ...
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45 views

Is there a rev matching device?

I understand that rev matching is acquired skill by practicing and driving more. I'd like to know if there was a device you could attach to your car that would detect and notify you if engine rev is ...
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4answers
2k views

RPM bouncing when in idle, especially when AC in switched on

I have a diesel common-rail 1.5l engined car. Lately I am facing an issue where the RPM needle is bouncing in the tachometer when the car is idling. The normal idling RPM is around 820. When idling, I ...
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1answer
199 views

How does the tachometer on my dashboard actually work?

Recently, I asked a question about the speedometer, how it works and how accurate it is. But that got me thinking... how does the rest of the dash actually work? I understand that the RPM measurement ...
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2answers
629 views

Checking the motor's RPM without an in-dash tach

I'm going to be doing a carb rebuild this weekend on an 84 Ranger. The truck doesn't have a tach, but I'll be needing to read the RPMs to properly adjust the carb once its rebuilt. Is there a way of ...
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1answer
129 views

Driving car with half engaged clutch

Say I am driving my car (Hyundai i10) at 2nd gear. My clutch is engaged. As I increase my throttle position, rpm will increase and so will speed of the car till a point when the speed wont increase ...
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3answers
3k views

What determines when an automatic transmission shifts?

I'm working on developing an automatic bicycle (mostly microcontroller based) and I'd presume I'd be shifting in a similar way to a car. So my question is, what factors does the transmission take into ...
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1k views

Why does my RPM drop when sitting idle at traffic lights?

While I'm sitting idle at traffic lights I put the car into neutral. The engine stays idling at about 1000 RPM. However every now and then it drops down to about 500 RPM and then quickly back up to ...
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1k views

Does using the entire rev range of a car damage it?

On my standard 2000 1.2 Opel Agila, I often have to get to about 5000RPM to join a fast road on a steep (1 in 10) hill, as it is gutless on hills. I have to do this almost every day, and I have ...
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RPM jumps up & back down at 40mph

My question is for a 2006 Dodge Magnum, 2.7 liter engine. Just over the past month or so, I noticed when I'm cruisung, just coming from a dead stop, when I'm at 40 mph my car kinda feels like it ...
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1answer
69 views

RPM problem Ford 2009 Crown Vic

I recently removed the car battery and plugged it again. I then noticed that when I turn the A/C on the RPM goes up and down 1000~500 rpm and sometimes when I shift the gear from N to D or R the car ...
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1answer
227 views

Can diesel engine be harmed as easily as gasoline engine by over-revving?

There is an excellent Q&A about why diesel engines have lower redline RPMs (about 4500 RPM) than gasoline engines (about 6500 RPM). The reason is related to the combustion of diesel fuel. However,...
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4answers
726 views

2015 Honda Fit iVTEC - Shifted into 2nd Gear at Highway Speeds

I was just driving on the highway and went to pass someone uphill, so I went to put it into 4th gear (from 5th or 6th). I somehow made the mistake of putting it into 2nd and the engine screamed and ...
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3answers
879 views

Toyota Corolla 2011 not accelerating when on 60mph or above

I recently bought a toyota corolla 2011 s from a local dealer with 80,000 miles on it. In my test drive everything seemed normal and was satisfied with the deal. But on a recent trip when i actually ...
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1answer
169 views

Can frequent engine lugging lead to blown head gaskets?

I've heard that prolonged driving at low RPMs (AKA "lugging") can cause head gaskets to blow. Is that true and, if yes, can you provide a lowdown of the causality?
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344 views

Should fuel pump noise be changing according to electrical load and RPM?

One thing that bugs me about my car is that the fuel pump noise is fairly inconsistent. Turning on the lights, aircon, defroster, etc. lowers the fuel pump speed and gives a lower pitched noise. It ...
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1answer
63 views

What is rev matching, and how do you do it correctly? [closed]

I understand that not doing this properly will destroy your transmission/synchros. What's the proper way to do it? I think I'm doing it right, but I've found most people's descriptions to be vague and ...
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0answers
29 views

Increase of RPM meter after reaching my destination [closed]

I'm driving Camry 2001 4 cylinder, automatic gear. Just recently I noticed that after reaching my destination, when I put gear to P, I find the RPM meter increase to reach slightly lower than 2, ...
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1answer
39 views

Honda City vTec Slow Start

I have a Honda City 2005 vTec Manual Transmission Car, which will be due for servicing in another 1000KM. I am not well used to driving manual car and I face a lot of traffic everyday going and ...
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1answer
189 views

Does shifting gears at 10000 rpm damage my car?

If you drive a high power gasoline sports or a muscle car with a manual transmission, will it do any damage if I shift gears at 10000 rpm?
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7k views

Is it bad to drive slow at low rpms in 4th or 5th gear? Do you get better gas mileage?

Obviously running your engine at too high an RPM for too long isn't good. But what about running it too low? not so low that it stalls or lugs, but within around 1,000 RPM? Would you get better ...
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3answers
4k views

Minimum RPM at idle speed

Looking at wikipedia, For a passenger-car engine, idle speed is customarily between 600 rpm and 1,000 rpm. For buses and trucks it is approximately 540 rpm. In case of many single-cylinder ...
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1answer
2k views

Automatic: revs dropping then stalling when stopped at lights

Kia Sedona 2012 automatic. Drove 180 miles on a full tank of fuel without any problems. Started the car the next day and it didn't start cleanly but did eventually. Was waiting on the drive with the ...
6
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4answers
2k views

Why does the power output peak and then drop as engine speed increases?

I have been looking at the power bands for my car (2000 Opel Agila 1.2) recently, as I want to work out when it is best to change gear and stuff, as I have no life! This is the approximate graph I ...
6
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1answer
884 views

Engine revs to 4000 RPM without pressing gas pedal

I tried to start my car today but something strange keeps on happening. It turns on just fine, but once the engine is operating it starts revving to 4000 RPM even though I am not pressing the gas ...
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333 views

1992 Mitsubishi 3000gt sl. no power and won't go above 2k rpm

I bought an automatic 1992 Mitsubishi 3000gt sl 2 days ago. I got it cheap knowing it would have problems, and that's why I'm here. When I put it in drive and slam on the gas the car just simply ...
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1answer
203 views

Installing an RPM meter

I need to install one in my car, as it doesn't have one, what modifications do I have to do? Edit: My car is: Suzuki swift 1996 But I would like the answer to be generic, as to what to look for if ...
7
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1answer
2k views

Why doesn't my rev limiter bounce?

I have a BMW 630i Steptronic from 2007. If I floor the pedal in neutral the RPM is of course limited, but it doesn't "bounce" like regular rev limiters. Instead it keeps a constant and "clean" RPM. ...
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5answers
15k views

What modifications need to be made to an engine to enable higher safe RPMs?

I first had this question while playing a racing game - it was a touring race with BMW 320i's, and I noticed that I could rev up to 8,500 RPM before shifting gears. Now my car (an older 320i), ...
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3answers
597 views

How do I reduce engine idling rpm without stalling it?

Considering idling losses are present in every engine, reducing the idling rpm might be providing significant savings. But, as I noticed on my bike, the chances of engine stalling increases with ...
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1answer
1k views

Suzuki GSR600 low idle revs and unstable

Just a week ago I noticed in my motorbike unstable rpm, +-300rpm. But today I found that the idle rpm are below 1000rpm, at some points around 500rpm (Normally is 1500rpm). I'm due for the annual ...
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4answers
4k views

Is starting idle RPM always lower in colder temperatures?

I've noticed that my 2008 Jetta 2.5L 5W40 generally starts up with an idle RPM of at most 1.2K RPM around the freezing temperature (say when the temp sensor reads 33°F), or even at just about 1K ...
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1answer
61 views

What Means Fuel Shut Off?

What does fuel shutoff means? I searched it up before, but the answer is not what I'm looking for. For example: The Ford Lighting's fuel shut off is at 5,400 RPM.