How often does engine RPM drop when idle?

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 about 1200 then goes slowly down to 1000 and stays there for a bit until I go again or it drops again. It only happens for a second or two and about 3 times a minute.

What should I do if my car idling is too high?

Vincent Ciulla is a certified master automotive technician who has diagnosed and repaired light trucks, domestic and foreign cars, and diesel engines, for more than three decades. If your car seems to be revved up to a higher-than-normal RPM while idling, it’s not necessarily a problem.

Why do you need to adjust the idle speed?

Idle speed adjustments can be made to improve the quality of performance of an engine. Adjusting an idle requires maintaining the car’s engine at operational speed. When a car’s engine is cold it uses more gas to operate.

Why does my car rev up when idling?

If your car seems to be revved up to a higher-than-normal RPM while idling, it’s not necessarily a problem. If this problem happens while the engine is cold, it may be part of the engine’s design.

What should the RPM be on an idling car?

When you start your engine, and just let it run without pressing on the accelerator or putting it into gear, that’s idling. A properly idling engine should be able to maintain a steady but low rate of revolutions, somewhere in the vicinity of 1,000 RPM.

When does a car have a rough idle?

November 27, 2017. It’s easy to tell when your car has a rough idle: When you start the engine, it won’t run at a steady rate. It may almost stall, or it may run at varying RPMs without your putting your foot on the gas, or it may do both.

What to do if your car is idling too fast?

A throttle body cleaning is likely to cure the high idle speed as well. There are many possibilities when your engine is idling too fast. Here are some common ones to help guide you towards the root of the problem.

How can I tell if my idle control valve is working?

To check if an idle control valve is working properly, start by turning on your engine and letting it run for a minute or 2. Then, when it’s at an idling speed, take note of the RPMs in your car. Next, turn the engine off and disconnect the idle control motor under your hood.

What does idle mean on a car engine?

Engine idle refers to keeping the engine running when the vehicle is not in motion. Generally, idle speed is just enough to keep the engine running without stalling out.

What causes the idle speed to be high or low?

What Causes Engine Idle Speed to be High or Low On a modern fuel injected engine, engine idle is controlled by the engine control unit (ECU) and an electrically operated throttle control module. When the idle is high or low, it could be caused by a malfunction of this system or any of the individual components that comprise the system.

Why is the idle air control valve not working?

When this happens, the job of the idle air control valve is to bring this deceleration down to a slow and smooth idle rather than suddenly cutting off the fuel supply causing the motor to die. When the idle air control valve is not working properly, this cause a disruption in this process resulting in the engine not being able to idle properly.

Engine idle refers to keeping the engine running when the vehicle is not in motion. Generally, idle speed is just enough to keep the engine running without stalling out.

When does idle come back to normal on a Harley Davidson?

Just seems to happen when I’ve been running at a fairly wide open throttle maintaining higher speeds for a while (fwy) or longer stints (catching all green lights) on the streets at a speed of about 45 or more. It always seems to come back to a normal idle after getting back into first gear when stopped, or when I start going again in 1st.

How to troubleshoot an idle that is going up and down?

Finding the ultimate cause of an uneven idle can be a trial and error process, but a cost-effective way to cure your F-150’s idle problems is to start by cleaning specific components to see if this restores a smooth and even idle prior to replacing components.

How does the idle speed of a car work?

This valve is controlled by the vehicle’s computer which will adjust idle speed based upon other measurements such as engine temperature, intake air temperature and electrical system load or voltage. When you accelerate, the engine RPM increases, and as you let off the gas, the RPM slowly returns to the normal idling speed.

What does it mean when your car is stalling at idle?

Problems with idle speed —things like slow idle, fast idle, rough idle, or stalling after idling for a few seconds—are symptoms that something is wrong with your engine. These should be investigated, diagnosed, and repaired as soon as possible.

When do I stop at red light RPM drops?

But when i stop at light rpm drop to 500. And feels like its going to shit off. My car has 80455 miles. My car has an automatic transmission. This may be a sign of a failing idle air control valve.

How long does it take for idle RPM to drop?

Sitting at a stoplight, after about 20 seconds, the idle will drop to about 200rpm, causing the whole car to shudder. It’s just like it’s about to stall. Then in like 2 seconds it’s back to 750rpm or so. No CEL lights or DTCs are thrown. Oh well.. at least it doesn’t completely stall I guess.

Why does idle speed drop during cold startup?

If the idle air control valve did not compensate for these, the idle speed would drop when certain accessories are used. In severe cases, the engine may even stall. The idle air control valve is most important on a cold startup. Problems with the idle air control will be most obvious during this time.

What does it mean when your car Idles down?

Idle car speed can change due to wear and tear. Fortunately, an adequate tune-up can restore the correct idle speed. What to Look For: Idle RPMs will usually drop below 600 RPM or whatever is typical for your vehicle. The idle speed feels slower than usual.

What happens when engine RPM drops below 800?

However, when the engine RPM drops below the normal range of 800 RPM (for most cars), it is more than likely that you are dealing with an IAC valve problem. In cases where this valve is clogged or is failing, your vehicle will stall instead of slowing to an idle after the release of the throttle.

When does the idle air control valve change?

When the engine is running but the vehicle is not moving, this means the engine is idling. During this time, the number of revolutions per minute (RPM) inside the engine will change. The idle air control valve is responsible for managing the engine idle speed.

Why does my Honda Accord not speed up?

If your Accord won’t accelerate, but the RPM’s go up it’s usually not going to be an engine related issue. Somehow, the power that your engine is creating is not making it to the rear wheels. This is typically a transmission related issue.

What does it mean when your car is idling but not running?

When the engine is running but the vehicle is not moving, this means the engine is idling. During this time, the number of revolutions per minute (RPM) inside the engine will change.

What’s the normal idle speed for a Honda Accord?

Around 800 rpm is normal sometimes if your intake manifold is dirty the computer doesn’t manage it right so it feels like your car is choking it gets as low as 400 rpm then you just have to remove your intake and clean the inside of your manifold

But when i stop at light rpm drop to 500. And feels like its going to shit off. My car has 80455 miles. My car has an automatic transmission. This may be a sign of a failing idle air control valve.

What to do if your car won’t idle?

The Fix: Set idle speed to specs. There may be some type of ignition problem. The Fix: Check and replace distributor cap, rotor, ignition wires, and spark plugs. There may be a fault in the computerized engine control system. The Fix: Bring your car to your mechanic or dealership to check the engine control system with a scan tool.

Is the memory / GPU clock slowing down at idle?

I noticed that my GPU and Memory clock now stay constant in Precision X. Before they would slow down at idle and my temps would drop faster as well. Is there a setting I’m missing?

What causes the idle speed to go up or down?

The idle air control valve is programmed to regulate and maintain the engine idle speed at a constant rate. If the valve fails or has any issues it can cause the idle speed to be thrown off. This may result in an unusually high or low idle speed, or in some cases a surging idle speed that repeatedly climbs and falls. 2. Check Engine Light comes on

When does the Mazda6 engine surge to idle?

First, when slowing down (as to a stop light) the engine rpm SOMETIMES doesn’t drop to idle as I approach the light. The engine wants to stay and around 1800 rpm and keep the car going. The brakes stop the car just fine, but the car wants to go. Second, when cruising at around 45 mph, the engine surges from 1800 rpm to 2200 rpm.

What happens when the idle control valve fails?

When the idle control valve fails it can cause all sorts of issues with the vehicle, and in some cases may even render it undrivable. Usually a bad or failing idle control valve will produce a few symptoms that can alert the driver of a potential issue. 1. Irregular idle speed

I noticed that my GPU and Memory clock now stay constant in Precision X. Before they would slow down at idle and my temps would drop faster as well. Is there a setting I’m missing?

Why does idle drop when the AC is on?

if the a/c is overcharged or the expansion valve isnt equalizing it can cause excessive resistence of the compressor wheel and excessive drag on the motor. Ive seen it quite a bit Loading… I have the same problem with my idle dropping when the AC is turned on and it was the ISC.

What causes engine rpm to drop at stop light?

engine rpm drops or stalls at stop light on abrupt braking. Hi there. In many cases, the issue you’re talking about is caused by an ignition timing problem; typically related to a damaged crankshaft position sensor or trouble within your ignition system such as the coil or distributor.

Are there any idle problems in my Jeep?

Drove car about 25 miles got on expressway took it to about 75 car ran great no idle problems at all. Got home and did the key thing to get code, and got, p0601 again, disconnected battery to clear code and it did but did the up and down again leveled out again but check engine light back on again.

What kind of car revs by itself when idle?

My car revs by itself when idle and sometimes it jumps one time it actually cut off also when it idle its over 1000 then goes down To around 500. My car has 139000 miles.

What can I do about intermittent RPM drop?

Or there’s the trusty but less effective soapy water method. spray suspect areas with soapy water, and if it starts bubbling, there’s a leak. Aside from leak testing you could find someone to log fuel trims, MAF readings, and 02 readings to see what is happening during the RPM event.

Is the Jeep Grand Cherokee a rough idle?

I have a 1988 jeep cherokee n it has a rough idle n a miss. It starts up fine n sometimes the rpms well stay at 3000 rpms. I sometimes have to turn the engine off n back on for the rpms to drop down to abt 1000.

Why does my Jeep Grand Cherokee shake when I idle?

Fouled plugs can cause a misfire, which in turn causes an idle shake. Spark Plugs – One of the absolute most common causes (if not the most common reason that your Grand Cherokee may be shaking) is the spark plugs. Although most modern vehicles use iridium spark plugs, they still need to be changed at the manufacturers recommended interval.

What should I do about my Jeep Grand Cherokee stalling?

Previously I changed the O2 sensors and throttle positioning sensor on my 2004 to fix idle issues. 2 years later having idle issues again the vehicle wants to idle at 1500 – 2000 RPM. Should I replace fuel filter and fuel pump? 21 people found this helpful.

What happens if a coil pack goes bad on a Grand Cherokee?

These packs are fired by the engines computer at exactly the right time to provide the optimal ignition timing. If a coil pack goes bad, it’ll cause a misfire and rough idle condition. Really, your Grand Cherokee will be running rougher at any RPM, but a misfire will be most pronounced at idle.

What should the oil pressure be at idle?

The oil pressure should not drop below about 20PSI. You should hook up a dependable oil pressure gauge and see what pressure is developed at idle. It sounds like you have an oil pump pressure relief valve that is stuck or a sender that is out. helpful? helpful?

Why does my oil pressure drop when I come to a stop and?

When I come to a stop the oIl pressure goes down to almost nothing and the red check gauges light comes on. Once I drive off, the check gauges light goes off and the oil pressure goes back to normal. Because the oil pump is engine driven. As the engine speed goes down, the oil pump output pressure decreases.

What to do when your car rpm goes down?

Hey friends if your car RPM goes down to zero then do following steps. 2.Make it Throttle body clean 6.Check if there is any gas leakage near by your car engine. Do All the above your car will be smooth and there will be no problem related to RPM. Was this answer helpful?

Why is it when driving the RPM gauge drops or jumps up?

Somewhere the fuel drop then suddenly rpm decrease better check the complete fuel system from tank to injectors also check the rpm sensor . Was this answer helpful? This could possibly be your output speed sensor, related to the transmission.

What does it mean when your car idles for a long time?

The idle of a car engine is kind of like a human heartbeat: You can tell what shape it’s in just by listening. Problems with idle speed —things like slow idle, fast idle, rough idle, or stalling after idling for a few seconds—are symptoms that something is wrong with your engine.

Why does the engine start at 600 rpm?

For gasoline cars, you have then a longer period where the minimum rpm is raised (over the warm “proper” idling which you quote for your car at 600 – 700 rpm) because the convertor and λ probe need to be warmed up asap so they start to work, even if you do not drive but idle.

Why does the starting RPM drop when it’s cold?

It is normal that the starting rpm is dropping when it’s cold. The battery is struggling a bit to deliver power needed to turn the starter. When it’s cold the engine shrinks a little and makes is harder to start. I will recommend you to start the engine and then let it run for a couple of minutes.

What should the idle speed of a car be?

This rotational speed allows the engine to generate enough power to operate vital components without turning off. The idle speed should feel consistent without skipping or slipping. In most of today’s cars, an idle speed of 600 to 1000 RPMs is average. If your car is idling rough, though, it won’t feel smooth.

Why is the idle speed of my car so high?

Step 2 – The idle air control motor (valve) is responsible for controlling the engine idle speed, if this part fails or becomes weak the engine idle speed could become erratic, additionally, this condition may or may not trigger the MIL (check engine, service engine soon light.)

How can I keep my car at idle?

Step 3 – Engine vacuum is a sealed system and must hold a specific amount to maintain proper idle conditions, inspect the engine vacuum hoses and intake gaskets. Step 4 – The air intake boot or tube is used to deliver air to the intake system of the engine.

When to remove an idle air control valve?

Because of the nature of this valve (large air volume processed) it should be serviced when a tune up is performed to remove “coking” which will hinder the valve’s performance. To perform a rough check of the idle air control, remove the valve while reconnecting the wiring harness.

What causes idle to drop way too fast?

Cammed autos sometimes may have an issue going 2-1 coming to a stop. If torque management is engaging on the closed throttle downshift, what happens is your idle will drop way too fast, and then overcompensate back the other direction. Idk about you]

What should I do if my idle is wildly oscillating?

If your idle is wildly oscillating, you need to raise base airflow, idle rpm, or both and start over. Take note of the idle quality. What I do is log desired idle RPM and actual rpm, plot them on the chart with identical ranges (say 500 to 1200 rpm), and take note of where my actual RPM is in relation to desired RPM.

What does it mean when your engine revs up?

If your engine revs up as you press down on the accelerator but your vehicle doesn’t accelerate as per usual or as you would expect, it’s a troublesome sign that can lead to a full-blown transmission failure. Transmission slipping, or gears slipping, is one of the most common transmission problems on both manual and automatic transmissions.

Why do engine rpms increase when the engine is cold?

There is a small solenoid in the throttle body that allows air through to raise the RPM while the engine is cold. Another issue is that your sensors may be out of range or not working while the engine is cold.

What should I do if my engine RPMs are too high?

If they are too high for a long period (above 6-7% for a long period) then there is a vacuum leak (buy a cheap ECU scanner and test this). If no vacuum leak you should remove the power socket from your IAC.

When do the RPMs go up or down?

For example, RPM’s quickly move from 1,250 to 1,500 at 45 MPH. This problem has been ongoing for two years (and driving me a bit mad). The condition is most pronounced when traveling between 15 and 45 MPH. I’ve never once noticed the condition at highway speeds (above 55 MPH.

What are the RPM’s of a car under constant throttle?

RPM’s rapidly fluctuate up and down even when on a flat road under constant throttle, speed and load. For example, RPM’s quickly move from 1,250 to 1,500 at 45 MPH. This problem has been ongoing for two years (and driving me a bit mad).

Why does my car cut out at 3500 rpm?

Tromp on it and she’s a tire shredding beast, untill it starts getting to 3500+ rpm, not so bad in 1st gear but 2nd is worse and 3rd is real bad. Damn thing starts cutting out/sputtering have to let off. Have checked the timing, spot on 38* all the way.

What are the RPMs of a 2005 LR3 HSE?

Discussion in ‘ LR3 ‘ started by Efecta, Aug 13, 2015 . 2005 LR3 HSE 4.4 with 156k miles. RPM’s rapidly fluctuate up and down even when on a flat road under constant throttle, speed and load. For example, RPM’s quickly move from 1,250 to 1,500 at 45 MPH. This problem has been ongoing for two years (and driving me a bit mad).

What does it mean when your car engine is idling?

Intake leak When you start the engine and let it run without pressing the pedal, it is called idling. When the engine is left in idling position, it maintains a steady but low rate of revolution approximately 1,000 RPM. The RPM needle stays constant, and this indicates that the vehicle’s engine is receiving the correct amount of air and fuel.

What does it mean when your car Idles smooth?

Smooth idling indicates that your engine’s fuel and air are mixing just right. What is rough idling? If your vehicle’s idle is rough, possibly rising and falling, or having difficulty maintaining a steady rate of rotation, you may have a problem that needs fixing.

What causes a leak in the intake manifold?

These leaks can result from a variety of causes, some of which are: 1 Hose wears out, gets brittle and cracks 2 Hose connection works loose 3 Leaking intake manifold gaskets 4 Leaking vacuum supply tank More …

Why does my Mercedes C class idle all the time?

This upset the vacuum lines that depend on a vacuum to maintain a steady idle. Check for vacuum leaks with a smoke generator injecting smoke into any vacuum line and see where the smoke comes out. That’s a leak that needs to be plugged.

Why does my car idle at high idle?

If this tube becomes loose or broken it can leak un-metered air into the engine effectively causing an unbalance (via the mass air flow MAF sensor) in the computer system which can produce fast or slow idle.

What causes the throttle body on a Mercedes to fail?

When there are throttle body malfunctions the wrong amount of air enters into the engine causing problems with air/fuel mixture ratio. Here is a close up picture of a Mercedes throttle body. Mercedes throttle bodies made by Bosch and VDO may fail. Luckily these units are repairable.

What happens to the engine when left in idling position?

When the engine is left in idling position, it maintains a steady but low rate of revolution approximately 1,000 RPM. The RPM needle stays constant, and this indicates that the vehicle’s engine is receiving the correct amount of air and fuel.

When an engine is running at idle speed it generates enough power to smoothly operate equipment such as the water pump, alternator, and power steering but not enough power to move the vehicle itself. A passenger car will usually idle between 600 RPMs and 1000 RPMs. A properly functioning idle should run smoothly without skipping or slipping.

Is it normal to have a rough idle?

This is definitely not a normal situation. If you are experiencing a rough idle or your RPM is running high, then there are a variety of reasons for why this could be happening. It is not always easy to diagnose the cause because there are so many factors involved here. Below are the top 5 causes that a mechanic would look for.

When does the RPM go back to normal?

The RPM will usually go back to normal as you accelerate the vehicle, but will increase again after you stop. This is definitely not a normal situation. If you are experiencing a rough idle or your RPM is running high, then there are a variety of reasons for why this could be happening.

What causes the engine rpm to go up when idle?

When the engine idles, there will usually be a misfire that you can feel just from holding onto the steering wheel. Furthermore, the RPM of your engine will be higher than normal when the vehicle is idling. The RPM will usually go back to normal as you accelerate the vehicle, but will increase again after you stop.

Why is the RPM on my Harley Davidson so high?

(Could be you went through 50 key cycles with no engine issues) When you get off the interstate & the idle is high,,, if you were to power it off and restart the bike, does the idle calm down or does it resume the high idle. Would help to know how high the RPM was, but you have no tach. (?)

Why does my car run at 1200 rpm?

Some cars, especially older cars with carburetors are designed to run at 1200 rpm or so until they are warmed up. And in modern cars, if you are running several accessories, such as the air conditioner or heater, the engine’s onboard computer may be telling it to run at a higher RPM to provide the necessary power.

Can a car run fine at 750 rpm?

This problem has been getting worse over the last 2 years. When the car starts it idles fine at about 1000 RPM. As soon as it warms up, it starts to idle rough, between 500 and 750 RPM. It almost quits running. As soon as you give the car some gas it runs just fine.

What happens when your car has a rough idle?

When your car is experiencing a rough idle, your engine may chug, vibrate, or shake while it’s running. This will cause your overall driving experience to feel rough and you’ll likely be bouncing a little bit in your seat from it.

What causes a car to idle at high RPM?

Like the human body, high engine idle RPM is typically impacted by the overall health of individual components including the throttle body, throttle linkage, idle control valve, EGR vacuum system and even the vehicle’s respiratory system – air intake filters.

What should my rpm be at when my car is at idle?

The idle RPM of a car depends on the type of engine your car has. For example, if your car has a 2.0 liter engine, the idle speed should range from 500 to 800 rpm. A ear with a 2.5 liter engine should have an idle speed from 550 to 750 rpm.

What rpm should the idle be set at?

For a passenger car engine, idle speed is customarily between 600 and 1000 rpm . For medium and heavy duty trucks, it is approximately 600 rpm. For many single-cylinder motorcycle engines, idle speed is set between 1200 and 1500 rpm.

What controls the idle speed of cars?

There are a few other engine components that can have an impact on engine idle speed including the following: Intake gaskets: The intake gasket is designed to maintain a consistent pressure inside the engine. Vacuum lines: Used to control the internal vacuum pressure inside the motor, the vacuum lines, like the intake gasket above can cause elevated idle issues if they are broken or Air intake: The job of the air intake is to move air into the engine.

Why does my car feel rough when the engine is idle?

This will cause your overall driving experience to feel rough and you’ll likely be bouncing a little bit in your seat from it. When the engine idles, there will usually be a misfire that you can feel just from holding onto the steering wheel. Furthermore, the RPM of your engine will be higher than normal when the vehicle is idle.

What to do when oil pressure drops to zero?

Depends on the car. But usually people first check continuity on the harness first, then check resistance on the pressure sensor and then resistance on the gauge. My 1988 4runner was doing the same, once engine warmed up, the pressure would read 0. In my case the pressure switch is cheap so i did trial and error.

Why does my car Rev by itself when idle?

It sounds like you may have a dirty or failing idle air control valve. The idle air control valve monitors the air intake as it is mixed with fuel prior to being injected into the engine at low speeds and at idle.

Why does my Volkswagon idle at 500 rpm?

As the start was too short and the engine was too low, the idle speed stays at around 500 rpm (approx. 50°C coolant temperature). Switch off the engine and immediately turn it back on. To stop this happening again, the starter motor must keep going for at least a couple of seconds.

What to do if your car Idles too slowly?

By using the “3” adjustment lever, start the vehicle’s engine to 3,000 rpm. The pump will have to be replaced if the engine speed drops too slowly or lags below the engine stalls, or the idle speed or even both. Inspect the adjustment of the cable throttle and adjust where need be. Also inspect the adjustment on the potentiometer.

What causes an uneven idle on an F-150?

A uneven idle on a F-150 can be a symptom of a variety of engine issues such as vacuum leaks, failed or dirty sensors or worn engine components. If the engine is older or has higher miles on it, the typical culprits will be dirty sensors and carbon deposits on engine head components.

What does it mean when your engine idle is too low?

If your idle is too low, it could be the IAC not talking to the computer correctly. Disconnect the IAC connector for a couple seconds while your engine is idling. If your engine idle didn’t change, you can suspect it to be the IAC. If it is working properly, unplugging it would cause your idle to freak out.

Why does my Ford F150 stall at low RPMs?

Of those two times, 1) Freeway: engine stalled when I pressed rolling. If I give it a little gas, it does just fine. It also seems to perform accord. We also acquired a camper recently and the truck did just fine the occasional stoplight. Selector Valve / Reservoir fixed the problem. I replaced that, but no dice.

What to do when your F150 stalls at idle?

Reconnect the battery and start it w/o touching anything. Allow it to warm at idle and then move odle paramaters. Drive it around town a few miles and see if all is well. If not, there are some other things that

When does a Ford truck stall while driving?

When it starts stalls. A few times the truck has stalled while driving, but I was down. Of those two times, 1) Freeway: engine stalled when I pressed rolling. If I give it a little gas, it does just fine.

What causes a truck to stall at idle?

Cleaning and/or making an adjustment to the throttle body may correct the problem. Engine running at idle, plug the IAC passage, and the RPM (revolutions per minute) should be at or near 400 rpm. A vacuum leak present could also cause the engine idle to be improperly controlled and needs to be identified before any adjustments are made.

What happens to your car when you idle it?

When the engine idles, there will usually be a misfire that you can feel just from holding onto the steering wheel. Furthermore, the RPM of your engine will be higher than normal when the vehicle is idle. The RPM will usually go back to normal as you accelerate the vehicle, but will increase again after you stop.

How is the idle speed of an engine measured?

The idle is measured by revolutions per minute or RPM. Idle speed can differ depending on the type and size of engine as well what the engine is being utilized for. An idle speed can be adjusted to fit the needs of a particular engine or action the engine needs to perform.

When the engine idles, there will usually be a misfire that you can feel just from holding onto the steering wheel. Furthermore, the RPM of your engine will be higher than normal when the vehicle is idle. The RPM will usually go back to normal as you accelerate the vehicle, but will increase again after you stop.

What does target idle speed ( EPR ) active mean?

Target Idle Speed(EPR active):The desired idle RPM when the exhaust pressure regulator is active in relation to coolant temp. Idle RPM (warm,not moving):Idle speed when vehicle is not moving and engine is warm. Idle RPM (driveaway):Idle speed for driveaway. Idle RPM AC Adder:This value is added to the base idle RPM when the AC is on.

What causes a motorcycle to lose power when accelerating?

There are six main reasons why a motorcycle loses power when accelerating which are: Plugged jet in the carburetor. Broken carburetor spring. Vacuum leak on the carburetor or intake boot. Carburetor spring is on backwards. Extra slack in the throttle cable.

What happens to your foot when you hit 4000 rpm?

If you were to keep your foot flat when it hits high RPM does it stay around the same RPM (as if it’s hitting the rev limiter) or does it force the car back down to 4000rpm then start climbing again?

When does the idle RPM drop at Nissan club?

I did some searching but didn’t find any relative information to my particular issue. 2008 2.5 sedan w/CVT. Just turned 3 years old and has about 70K on the OD. Injen WAI, and the K&N is cleaned twice a year. Issue: When I come to a traffic light and after about 10 to 20 seconds, the idle drops about 100 RPM.

What should the idle speed be when holding the brakes?

You brake system relies on vacuum and an idle speed that is affected by holding the brakes probably has a weak vacuum. You can get a cheap gauge at an auto part place that will quickly tell you if you are in spec. Idle air control..it should idle at 1000 rpm’s when the engine rpm’s jump up and down,suspect the iac.

Is the throttle internals of a gasoline engine Dirty?

I am presuming this is a gasoline engine. If so, the symptoms sound very much like the throttle internals are dirty.

What causes the Check Engine light to turn off at idle?

At idle, the ECM will not get the correct information and the throttle will variate randomly causing idle surges. The check engine light will randomly turn on and off even if the car is running smoothly without any jerks and stalling.

Can a bad throttle position sensor cause idle surging?

Idle surging can be caused due to other issues in the car, but if it happens in conjunction with other throttle position sensor symptoms, the culprit is often the TPS. At idle, the ECM will not get the correct information and the throttle will variate randomly causing idle surges. 3) Check Engine Light

What causes idle surges on a car ECM?

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