Q: engine revs up and down when in park

asked by on April 21, 2016

engine revs up and down when in park and when driving

My car has 130170 miles.
My car has an automatic transmission.

Car idle is rough Inspection $79.99 - $89.99 Get a Quote

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.

A mechanic will be able to diagnose the rough idle for you and quote the needed repairs. For this vehicle, the engines are very sensitive to vacuum leaks in the intake air tube, between the mass air flow sensor and the throttle body. If the tube is cracked it will need to be replaced before anything else to see if the idle settles down.

The statements expressed above are only for informational purposes and should be independently verified. Please see our terms of service for more details

Get an instant quote for your car

Our certified mechanics come to you ・Backed by 12-month, 12,000-mile guarantee・Fair and transparent pricing

What others are asking

Can you explain to me what parts are included in the Powertrain warranty that I have for my 2012 Honda Civic LX?

Hello. Your power train warranty does cover the hard parts of the power train like the ones that you mentioned. Typically this does not cover the suspension and steering parts as those end at the bumper to bumper warranty period....

What can cause an oil filter seal to blow?

The oil filter seal (to the block) could fail if the old seal was left in place and the new filter was installed over the old seal. In that case, the old seal will often dislodge and the oil will...

Sometimes my car accelerates very slowly but the RPM rises

Hello. I would recommend first checking the connections to the MAF sensor and cleaning it as sometimes they will get dirty and cause this kind of problem. If this does not work you may need to have it replaced. If...

How expensive is it to repair a timing chain in 2002 Altima 3.5?

Hi there. Check the engine light and see what codes are stored or pending in the computer (ECM). For the oil leak, look around to find where the leak is coming from. If the leak is coming from the top...

Random Misfire on Nissan Sentra

There are at least two recalls of the 2003 Sentra involving engine management issues. Consequently, you should first check your VIN at the NHTSA website to see if your vehicle is affected by any recalls. Carefully check the EGR system....

Bad idle air control valve

Hi there. I would need to know what the codes are to know if they are related. The idle control valve failing can cause other codes to come up, but there are other problems and codes that can come up...

I'm having trouble replacing the cv axle. Do I need to replace the rings around the spline that goes into the transmission?

The rings you are pointing to in the video are actually the retaining rings. Unless they are broken, they really shouldn't need to be replaced. The ring on the male part of the splined shaft should pop into a groove...

Would a wheel bearing be making my car sound like it's reving/ humming

The noise you are describing is very characteristic of a failed wheel bearing(s). Wheel bearing failures are surprisingly common but the part is, in fact, subjected to extreme forces even in normal driving. Sometimes just a big impact with a...

My radiator went out but I have to pump on gas for it to start

Pumping on the gas does not do anything with a fuel injected car. Try just holding gas pedal at 1/4 throttle and see if it starts better? As far as the hard start if coolant went all over engine you...

Related articles

The Best Used Cars to Buy If You're a Teacher
If If you are a teacher, probably foremost on your mind is getting to school on time. You would also probably like a used car that is easy on gas and not terribly expensive, and will hold your gym gear...
A Buyer’s Guide to the 2012 Nissan Maxima
The The Maxima is one of the most popular vehicles from Nissan, and they’ve been hitting it out of the park in recent years. The 2012 Nissan Maxima is a fantastic, practical vehicle that offers some excellent performance for a...
The Best Used Cars to Buy If You’re a Vet
The The best car for a vet to own largely depends on the type of practice he or she has. Large animal vets are probably going to want something that delivers a fair bit of power, and possibly even towing...