Your car idles up and down when ac is on?

Cars & Vehicles

Probably because the compressor is cycling on and off to maintain temperature without freezing. Compressor on car runs slower RPM, compreesor cuts out and RPMs go up.

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Why does car rev up and down when in idle?

I can't say for sure what the exact cause is of it. however, i had a friend with a manual transmission Honda Civic that would do the same thing, he says it has something to do with the O2 sensor. so that gives you a starting point to find the problemidle airflow metre is more than likely the prob...

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Why does the ac work when parked but when you drive your car it blows hot then cold and idle goes up and down?

Many ac systems use engine vacuum to operate the ac controls. You may have a cracked or disconnected vacuum line that feeds the HVAC system. Check the vacuum lines under the hood, that is where they would most likely be damaged. A vacuum leak would also be the cause of the erratic idle.

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Why does your engine idle up and down while driving?

Could be your MAP sensor or Absolute Manifold Pressure sensor same thing usually mounted on or near the firewall and has at least two hoses"vacuum" going into it.

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Your temp gage goes up then back down when idling?

It is normal for a temperature gauge to go up a little bit until the thermostat opens up and the cooling fan comes on. As long as it is not going out of the normal temperature range it is fine.

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When you crank your car why do it be idling up high and then it idle back down to normal?

When you crank it? What are you driving a Model T Ford?

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When your running lights and ac is on your truck shuts down what causes this?

Bad charging system? alternator or generator does not supply enough power to keep battery charged to operate accesories.Bad battery? can't hold charge.

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What causes car to idle up and down when in park and then cuts off?

It is difficult to diagnose a problem like this via the internet, but it could be the air flow meter.A faulty air flow meter will often cause this type of symptom. Its a good place to begin the process of elimination, at least

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Why does your 88 sundance idle up and down only when its warmed up new plugs and wires also new fuel and idle control sensors?

check air filter or vaccum lines

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Why does truck idle up and down?

An idle surge can be caused by multiple phenomena.The idle air controller is simply a computer-controlled motor that controls idle.There could also be another sensor that is telling the computer to compensate, and in turn, this causes the idle to surge as it looks for the correct RPM level.

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What if your ac feels cold at idle but gets warm when running down the road?

U should prolly pusome more compressed liquid nitrogen because youre prolly running out. and the cahh gets too hoott for the nitrogen to stand it.

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Is an oil gauge supposed to go up when you accelerate and back down at idle?

Yes, this is normal.Found out this can be cause by a faulty oil pressure switch best known as oil pressure sending unit

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On a 1991 Nissan maxima Idle is good at starting car then the idle goes up high for a while then is up and down?

A faulty camshaft can cause your 1991 Nissan Maxima to idle erratically. A diagnostic test could verify the cause of the improper idling speed.

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When your 97 town car ac is on the idle speed changes?

Running your Air Conditioning puts a load on the engine - this is normal, the engine is working harder when you turn it on. You'll get worse gas mileage as a result.

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What does it mean when your car's engine shudders after it is warmed-up and idle?

The top motor mount is worn out. It would have helped knowing the car's year, make, and model, but, if your car's engine shudders after it is warmed-up and running idle, then it is probably a symptom that your vehicle needs a tune-up (i.e., new spark plugs (assuming it isn't a diesel), change the...

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When cold the civic idles up and down What could cause this?

incorrect choke adjust ment. when cold if choke is working correctly the car will idle higher until warm enough for the choke to release.It Depends on the year of the car as to whether it has a choke or not. If it fuel injected it will not have one. If that is the case it could possibly be due to...

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What causes your car rpm at idling to bounce up and down every time you switch on your car air-conditioning unit?

Clean or replace your Idle Air Control Valve.(IACV)

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Why would your truck bog down when the ac is on?

could be that the compressor is binding up,could even be that its over/under chargedIt takes as much as 10% of your engines horsepower to run a/c

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Why does car heats up when ac is on?

The car seats because of the extra energy it needs for the AC compressor work

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What causes your car to speed up when ac engages?

Vehicle could have a solenoid type switch to increase idle to compensate for load on engine caused by A/C compressor

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An alarm sounds inside the car then the idle speed goes up and down any idea?

have a bad sensor somewhere,take to get the computer read somewhere,ie most auto parts stors can do this at no charge

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Why does the car idle up and down while in park?

check coolant level, also check for a vacuum leak.

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What does it mean when your car temperature gauge goes up and down?

If the coolant temperature gauge is constantly fluctuating then the most common cause of this is a bad thermostat.If the thermostat is sticking or not opening and closing right then this will occur.It can also be a clog in the radiator or a water pump problem.

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Why do your car ildle up and down?

Maybe your throttle positioning sensor is bad.

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Can leaving your AC on when your car is not running hurt the AC System?

no, when your car is not running, that means that the compressor isn't getting voltage to engage. basically all you are doing is running your blower motor.

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94 civic enigine bogs down randomly and puts out huge amounts of white smoke Idle is fine on start up then mins later its jumping up and down. I had it worked on 3 times already and cant find problem?

Do a compression test. I think you might discover a crack in the cylinder head or blown head gasket. Hope not, but that's what it sounds like,

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Why would your car shake when you are idling and have the AC on but not as much when you are driving?

The car vill vibrate because the A/C system uses a compressor that runs off the engine's pulley system. The compressor is quite hard to turn and as such will actually use a few extra horsepower to run it, this results in a drop of the rpm from idle. Depending on your car, most petrol engines idle...

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Why would a car idle off directly after starting when the ac is on?

No expert here, but when you first start your engine it is cold and needs time to heat up before it works properly. Your AC unit may be putting strain on the cold engine (stiff bearings, warped shaft), meaning that your car will simple give up at trying to run due to the increased drag on it

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Is it OK to idle car with AC on?

So yes, idling with AC will hurt your engine but only if your vehicle doesn't have an efficient radiator system, such as an older model vehicles.Over heating is basically what would cause the engine to wear quicker.If you can avoid that, then doesn't matter if the car is running at highway speed ...

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Subaru 2.2 will not idle smooth when cold. the idle will jump up and down from 400 to 3000 rpm when cold. once it warms up the idle will stay around 400rpm. what would cause this?

The Subaru engine could have a vacuum leak, bad head gasket, stuck choke, or several other things causing the problem. Any of these could give problems then ease up as the engine warms up.

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Is it bad to idle car with AC on?

As long as the car's cooling system keep the engine in normal operating range you can idle your car indefinitely.Its not the best for the engine but its not terribly bad, either as most cars are engineered to be able to do that.It create wear and tear on the engine but it's at low torque.so per h...

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1987 Toyota Camry ac works until engine spontaneously idles up appx1500 rpm at which time ac compressor still runs but air temp gets warmer New timing belt Car does not idle up without ac on?

Warm air coming from the air conditioner compressor should not have anything to do with the timing belt. You probably need to recharge your air conditioning system.

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Why is my car overheating and revs up and down?

There are several reasons why your car may be overheating. Check the thermostat to be sure it isn't stuck. If the car revs up and down, the timing may need to be adjusted.

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What is wrong with Isuzu trooper 3.0 dt idling up and down and white grey smoke from exhaust?

Sounds like you need a ring job, white/grey smoke from the exhaust usually means oil is burning in your engine. Your engine may need a tune up or a compression check, bring it in to your mechanic.

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Does the temp gauge go up when your car is in drive or idle?

You should notice some rise in temp because there is no air flowing through the radiator, or at least not as much as there would be if you were driving. A vehicle with a mechanical fan will notice it less than one with a thermostatically controlled electric fan.However if the temperature rises ab...

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What is wrong when your car sputters at idle and when you rev up engine it sputters then kicks in and fuel comes out tailpipe?

need to check your evap system or you have a blown head

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What if your 96 avenger is stalling when you start it up and when going down the road it jerks?

You have not provided enough info, I recomend you have it checked by a knowlegable person.

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How do you fix idle going up and down 87 Chevy?

Look for an intake manifold leaking at a cracked or disconnected hose or one of the gaskets to the cylinder head or throttle body.

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What does it mean when your battery gauge goes up and down?

Now you know though what it means when your battery gauge jumps up and down.You know that it doesn't mean that the battery is bad, but instead normally means that you have an issue with the alternator.You should understand better why that is the case and you also know some things to check and way...

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What causes the rpms to go up and down at idle?

I would look for a vacuum leak under the hood. If the check engine light is on have an auto parts store read the code(s). The code(s) will help you find the source of the problem.

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What would cause engine to idle rough and die when car slows down or stops?

It depends on what kind of car you have. Three things are needed to "make fire" in the engine: fuel, air, and spark. If any of these is interupted then it can sputter or just not run. How those three gets there depends on the car. Older, carbureted engines mixed fuel and air in the carburetor and...

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1997 sunfireMissing when idle and wont rev up?

what type of motor is it? the quad 4 or the 2.2

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What does it mean when your temperature Gage goes up and down?

If the coolant temperature gauge is constantly fluctuating then the most common cause of this is a bad thermostat.If the thermostat is sticking or not opening and closing right then this will occur.It can also be a clog in the radiator or a water pump problem.

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What does it mean when your oil gauge goes up and down?

It could indicate an issue with the gauge (like a leak in a mechanical gauge), but it most likely means an engine component has worn down, creating a drop in oil pressure.By fixing or replacing the part quickly, you could avoid major—and expensive—engine damage down the line.

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What does it mean when your temp gauge goes up and down?

If the coolant temperature gauge is constantly fluctuating then the most common cause of this is a bad thermostat.If the thermostat is sticking or not opening and closing right then this will occur.It can also be a clog in the radiator or a water pump problem.

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Why would a 1997 grand am gt idle rev up and down?

A vacuum leak can cause that.

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What causes a 85 caddy throttle to increase engine speed up and down at idle?

A broken or maladjusted IAC valve.

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Why is my AC not as cold when idling?

Overheated engine Another common reason for car AC not blowing cold air when idle is an overheated engine.The compressor of the AC system moves heat from the radiator to the condenser.

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Why is my AC not cold when idling?

The cooling fan in the condenser is the first thing that you should look into while finding out the reason for car air conditioner not blowing cold air when idling.If the fan is damaged or cannot run with its full force, it cannot cool down the heat coming from the Freon (refrigerant) through the...

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Why does your truck heat up when you turn on the AC at a stand still?

Sounds like the condenser isn't getting enough air flow over it. Maybe your fan its operating properly

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Why does your integra rev up and down?

try checkin the mass air flow sensor..sometimes they do that...also have the computer scanned at an acura dealer if you cant fugure it out...the car might even have a recall from the factory over this matter..chack that too

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Why does your 97 caddy sls overheat when going up hill with the AC on?

Because the AC uses a rather large amount of power. Maybe you are almost out of water/anti-freeze in your riadiator.

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Your car is overheating when idle at stop lights or when idle in your driveway also when you are idle in the driveway and press on the accelerator it makes a water gurgling sound what could cause this?

The overheating could be a problem with your cooling fan- The water gurgling, I'm not sure aboout, I suggest you check all you fluid levels edit by SkydiveSonic: Sounds like you may have a lot of air in the cooling system. Try pouring more coolant into the radiator (when the engine is cold!!), or...

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Why does your truck bounce up and down while driving?

Bad shocksthey cause extra bounce in the ride, replace if necessary.To Test:How to Test Your Shocks By an eHow ContributorShocks are an important part of your car's safety system. If they are not operating properly, you are not only getting a bumpy ride, you are also endangering yourself and your...

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When sitting with vehicle in gear it idles up and down and temperature gage goes up what is the problem just recently had a tune up and fuel system cleaned?

take it to a mechanic for a diagnostic

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2002 Pontiac firebird idles hard when ac is on only how to correct?

An air conditioning compressor places a heavy load on an engine, especially when the engine is idling. If the engine is running rough at idle with the a/c on, try changing the spark plugs, air filter element, and the oil and oil filter. If your car has a four cylinder engine, you may have to turn...

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Why is my cars rpm going up and down?

Most likely you have a clogged (or failing) idle air control valve.Take it out, clean it, put it back… should solve the problem.There's a disconnect between the amount of air the computer thinks your engine is getting and the amount it's really getting, so it keeps trying to correct itself and al...

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What does it mean when your car's engine races revs up and down while it is warming up in the morning?

When an engine is warming up the car may idle erratically. This happens because the air may be to cold and the colder air will cause abnormal combustions to ensure in the engine. The computer is set to make the engine function under certain conditions, such as having the engine operate at an opti...

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How long can I idle my car with AC on?

The engine should be able to idle and power the air conditioning and not overheat, even on a hot day in a tropical climate.Eventually you will run out of fuel and that will be the limit.Assuming a 17 gallon tank and .17 gallons per hour you can run the car for about 100 hours at idle.

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When you see down in a car it is fast and when you see up it is slow?

this is because you are very close to the ground, but far away from whatever you see when you look up. Because of this, the angle of your neck will change quickly to stay looking at one spot on the ground, but because the sky is far away, the angle of your neck will not change as rapidly. It's ha...

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Why your car stop when the ac turn on?

bad alternator or ground to ac compressor

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What causes speedometer and tachometer to fluctuate at idle on 96 grand am and cause engine to rev up and down for some minutes then stall?

Do you have a check engine light? If so, get it scanned by a repair facility to make sure you don't do any unnecessary repairs. It could be many things, such as an o2 sensor or throttle position sensor just to name a couple. If you don't have. Check engine light, sounds like a faulty engine contr...

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What to do when your car breaks down and you still owe money on it?

Sell the car as is to a private buyer, put the proceeds toward the car loan, and then either: 1) keep making payments on the car loan till it's paid off, or 2) take out a personal loan with better terms from your bank or credit union, and pay off the original loan with the new one.

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Why does your ac come on when you turn on the heater on your car?

The AC takes the moisture out of the cabin air and that helps clear the inside of the windshield from moisture faster.

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Why does your car vibrates when the ac turn on?

The engine may be in need of a tune up.

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What happens when your AC is low on Freon?

That's because the low pressure in the can quickly lowers temperature.Well, something similar to that happens in your air conditioner is low on refrigerant.When the evaporator coil freezes, cold liquid refrigerant flows through the refrigerant line, causing the surrounding moisture in the air to ...

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When you shut up ac of your car water is getting drain this is ok or not?

If your ac is working well and is on in humid weather it will dehumidify the air and can drain quite a bit of water which you can see especially well when stopping the car it will drain underneath the car usually near the firewall in the desert when dry it might not drain at all but the more humi...

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Why does ac condenser fan not run when car is idling?

The condenser fan is more likely to run when the car is idling. So if it NEVER comes on when idling you definitely have a problem. If the condenser is not cooled, then your compressor could get overloaded. It may be a problem with a relay that is preventing the fan from running - or some other is...

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What makes the lock go up and down when you press the car key?

In cars with central locking, or remote locking, a solenoid is fitted to the locking mechanism. When the remote button is pressed (usually on the key) a signal is sent to the central locking control system. The received signal closes an electronic gate in the controller and current from the cars ...

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Problem when pulling off or accelerating car boggs down starting and idling of car fine 1996 Dodge Avenger V6?

Try getting the fuel injectors cleaned. They had to flush mine twice at the dealership. Cost less than $200. Was well worth it.

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Who do you notify when a ATV is running up and down a paved road?

Your local law enforcement agency.

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Why does my car not heat up when idling?

The engine makes very little heat when idling, and if the thermostat does not close, the engine coolant temperature may drop low enough that you'll get no heat from the heater core.If the coolant level is low in some cars, the water pump may not provide any flow to the heater core at idle.

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Your car sputters in idle and acceleration?

take it to a garage there may be something wrong with the fuel delivery system.

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Why does my car engine rev up and down when in park?

The idle valve is probably stuck. It probably needs to be changed. ----------------------------------- This may also indicate a vacuum air leak. My Odyssey did this recently. The idle and all other vacuum systems are connected. If one leaks, the idle may be effected. Question: Is your TCS light c...

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What if your car is over heating and when you put the heater cools it down?

fan not working or coolant level too low or fins on radiator loose

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What causes a gas smell and gas spitting out the tailpipe on a 95 s10 blazer it floods sometimes when started and kills the battery and idles up and down?

Fuel coming from the exhaust could mean that a cylinder is not burning fuel correctly. Check the spark plugs to see if one is burnt or colored differently. This one will be the cylinder with the problem.

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What is wrong when your car loses power while idled?

usually if you leave it on too long the gas intake offsets the power converted to the motor because your battery is charged by your alternator and if no acceleration of the motor shafts takes place the alternator will lose tracttion on the belts and your battery will die so next time you go to th...

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Why does temperature go up when idle?

cooling fan not working

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Why does my temperature gauge go up when my AC is on?

It's normal for the temp gauge to rise with the AC on and moving in slow traffic.When the AC is on the condenser that sits in front of the radiator releases heat.This heat is then transfered into the radiator which causes the coolant temp to rise.

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Why does the rpms go up and down when the engine is in indle?

This is often the result , in fuel injected cars, when there is an intake manifold vacuum leak ( i.e. loose or disconnected vacuum line, intake gasket leak , injector seal leak or many other possible leaks in the air intake system ). It is also a symptom of a faulty or maladjusted throttle positi...

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Why does your car jerk when the ac is running?

Please go check the cooling fluid level in the car- it's probably low and needs to be filled up.

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Why would your car die when idling?

You do not provide enough information for a good answer. It depends if it is Fuel Injected or not and other information. Possibly vacuum leak or idle speed too low.

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Why does your car overheat when it is idling?

It usually means the electric fan is not working, but I would also check the coolant level.Note that not all cars have electric fans, and the above recommendation to check the coolant should be followed, but there could be other reasons, such as a blockage in the cooling system or damage to a sys...

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What does it mean when during the first 25-30 MPH your speedometer needle starts to wiggle up and down?

Probably you will need to remove the speedo cable and clean and lube it

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Why does your 1997 neon not accelarate properly and bog down It does it more when going up hill?

Sounds like the fuel filter. Could be bad spark plugs too. Check the fuel filter first. Easier job.

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What can slow your car down going up hills?

gravity. Going uphill is always harder thatn going along the flat.

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Why does the fan not start on your car when it is idling?

electric fans are run by a sensor that turns it on when the engine has reached a certain temp. if the engine isn't hot enough or isn't workin hard enough the fan wont kick on

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1999 Nissan Frontier and have tuned up and replaced almost everything Uses a lot of gas and bogs especially when the ac is on - any ideas?

I've got a 98 Nissan Frontier that doesn't get very good gas mileage. Engine is rather underpowered....I believe it's straining to move the vehicle along.

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I have a 1992 cadillac seville. when i start the car it idle high and will not come down?

First you must check the ISC motor ( idle speed control) operation. Its located by the throttle body. It controls idle and high idle speeds. Good luck

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Vectra 53 2leter when you strat engin its shaking and race going up and down?

its out of time needs reset ,

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What would cause a car to rev up and down?

The idle is controlled by the idle air control valve and if it cannot keep the engine idling it will keep trying to rev the engine up to compensate.A vacuum leak, sensor that has failed, or an EGR system malfunction could potentially be the cause of the erratic engine you're experiencing.

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Why does my car rev up and down?

The idle is controlled by the idle air control valve and if it cannot keep the engine idling it will keep trying to rev the engine up to compensate.A vacuum leak, sensor that has failed, or an EGR system malfunction could potentially be the cause of the erratic engine you're experiencing.

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Why is the brakes locking up when i slow down?

Calibers are sticking. You will need to replace the calibers that are sticking and flush all the old brake fluid out of the system then replace it with fresh fluid.

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What is wrong with a car that only picks up speed when ac is off?

it is totally normal especially for a 4cyl car your air conditioning is compressing airso that why it is sluggish with it on

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Why is my speedometer going up and down?

Hello.The crankshaft position sensor will not cause a fluctuation in the speedometer gauge.If the speedometer is acting like this then most of the time this is caused by a failure in the vehicle speed sensor.When this sensor or the connection at the sensor fails then this will happen.

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Car shut down after open AC?

look under the hood and rev. your engine the piece that moves is the throttle on the throttle there is a wire you need to take the wire and move it back so there is more wire exposed just grab the wire with a clamp and move the throttle up and you should be fine.

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Why tachometer needle jumps up and down?

A cars tach jumps and runs with engine rpm.Sometimes if it jumps and changes engine sound,the throttle position sensor needs changing.If it jumps with no engine speed or sound change it means your alternator is going bad.

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Integra temperature gauge is moving up and down?

probably means u need to change the coolant for the car,leaking coolant sumwhere

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Why is my fuel gauge going up and down?

gas gauge goes up and down while driving on flat roads.The most common cause of erratic fuel level is caused by a defective fuel level sender in the fuel tank is defective or out of position or restricted from going all the way up to full position.

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Why is my temperature gauge going up and down?

Hi There, It sounds like you may have a sticky thermostat or potentially a cooling fan that may be working intermittently.When the thermostat is stuck open it can cause the coolant to circulate constantly resulting in the motor never reaching the correct operating temperature.

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Temp gauge goes up and down?

Could be low on coolant (leak somewhere) or the thermostat is faulty.

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