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try changing your TPS (throttle positioning sensor) its located on the intake area (look where the throttle cable hooks to the engine) Possibility of a fuel pressure regulator problem. Also a faulty Idle Air Control motor (IAC) could cause the problem. ask a local repair facility for assistance. I had that problem with my grand prix. Replaced everything I could think of. turned out to be that the computer needed to be reset. possibly a vacuum leak...check hoses, you may need to replace you intake maniflod gasket

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โˆ™ 2006-04-11 10:00:40
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Q: Why would a car idle rev up and down?
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Related Questions

What would cause a car rev up and down by itself?

idle airflow metre or pipe may have come off carb check both

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

A vacuum leak can cause that.

Why would a 93 Honda Civic idle up and down after you rev the car up?

Check the Idle Air Control. It might have carbon deposits and need cleaning. Also do the same for the throttle body intake. It might also need cleaning.

When my 94 town car is in park if you shoot a rev to the motor it will rev up then drop down below idle speed almost stall or stall but will restart again?

ID-ten-T error.

Why would your 1995 Chevrolet Monte Carlo idle real fast and then real slow rev up and slow down?

A vacuum leak or a dirty or defective Idle Air Control Valve will cause an unstable idle. jd

Why would a 1992 Chevy astro cs rev irratically in idle?

vacuum leak, bad idle control sensor

Why would a 1996 sebring stall and rev up in idle?

intake gasket is leaking

Why does car engine rev when it's very hot outside?

I'm going to guess yo have the air on, that would mean that the idle compensator is out of adjustment and over revving the engine.

How do you check BMW drive by wire?

Sit in the car in neutral, rev the car to 2000 revs then apply the break firmly whilst still holding the car at 2000 revs. If the idle drops back down then the car is drive by wire... so ive been told anyway! :)

Should you rev up your car continuously while starting?

no, you should let it idle and warm up a little bit.

Why would a car stall when you put it in park?

What car is it? what year? is it a diesel or petrol? could be you r base idle?? but need know more info..... does it stall in drive with foot on brake? does it rev high?my car is a 07 Chevrolet Colorado,standar

Why would your 1995 Chevy Monte Carlo idle real fast and then real slow rev up and slow down?

change the TPS sensor, (throttle position sensor).

What would make the rpm needle rev up and down in 1990 Honda civic while the car is in PARK and running?


What would cause the engine to rev to full throttle when throttle position is at idle on a polaris magnum 325?

It may be that the idle is set at max rpm on your carberator

What does it mean when your car excelerates without having your foot on the gas?

More than likely it is your idle control sensor. It will idle, and then all of a sudden by itself rev up. If it continues to rev constantly your throtle cable may be broke, the spring, or possible the cable is catching on something

When car won't stop when braking and slightly accelerates?

Your car is gearing down to first and to do that it has to rev a little

Why would a wrangler idle high after warming up?

check your Idle sensor which is attached to your throttle body. This ussually goes bad and tends to rev the idle up. I had the same problem with my 99 wrangler.

Why 86 Honda Prelude rev up and down?

check your idle air control unit also called an IAC motor

Why would your car rev up and shake?

If the rpms are above normal the most likely problem is a vacuum leak at the intake side of the engine. This condition will also typically cause a rough running situation at idle. Another thing that could cause a car to rev up and shake is a bad ecc(computer). also check your motor mounts if you have an old car.

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 problem idle airflow metre is more than likely the problem It may have a clogged (fouled) fuel filter.

How do you get a 1989 Ford Laser to idle?

you have to turn the idle screw down ?? ? ? ? ? ? ? ? ? ? there are 2 of them. one on the right and one on the left. the left one is general idle and the one on the right is for air-conditioning idle and high power output idle ( rev higher ) A vacuum line may have come off if it has started revving.

Low revs causes car to cut out?

You may need to adjust the throtle or idle of the car. In older cars this is as simple as tightening a cable. So when the car is just idling it will naturally rev higher and not stall.

Why does a car idol high when shifting gears?

Typically this is caused by the load being removed from the engine, allowing it to rev faster and thus idle higher.

What causes a Briggs and stratton engine idle speed go up and down?

The most common cause of engine surging (rev up and down) is a dirty air filter.

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