Q: Car racing and idling high

asked by on March 28, 2016

The car is racing, and the low idle is too high. The RPMs do not go all the way back down when I lift my foot off the gas pedal. I personally replaced half of the O2 sensors, but the front right is rusted in. But I doubt that is the problem. Also, the dash light indicates the trunk is open most of the time. It seems as if there is a bad sensor.

Engine idle speed is high Inspection $79.99 - $89.99 Get a Quote

Hi, these cars have developed many idle issues over the years and there are a few things to check. All the linkages for the throttle should be inspected to make sure that when you release the pedal, the return spring closes the throttle all the way. You should also have the engine inspected for any vacuum leaks. Our certified technicians here at YourMechanic would be able to inspect your engine and help diagnose the trunk sensor.

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

RPMs are fluctuating during idle - 2014 Nissan Altima

Hello. The first thing to check is what problem codes are setting the Check Engine light. The throttle position sensor, a clogged fuel filter, or dirty throttle body could produce the symptoms you describe. Most auto parts stores will read...

Car shuts off suddenly - 1987 Mercedes Benz 560SL

Hey there. I would check to make sure your mass air sensor is cleaned out and that the intake air system is completely sealed. If the mass air sensor gets dirt in it from an air filter housing that is...

Why is my car accelerating by itself?

This vehicle engine has a manual throttle cable and cannot accelerate by itself. You may have a faulty idle air control valve that can cause a high idle but is limited to only about 1250 rpm. I would recommend having...

Water blowing out tailpipe.

The first thing I would have to ask is if the cooling system is getting low on coolant. Does the engine run rough or misfire? The water coming out of your tail pipe may be just that, water due to...

Gas pedal unresponsive, then suddenly jerks the car forward - 2015 Nissan Rogue

Hello. The new electronic throttle systems are very sensitive to a driver using two feet to drive and if you are still touching the brakes and trying to accelerate it will not let you. This programming is due to all...

Misfire on cylinder 8

It could be the spark plug, ignition coil, or coil boot causing the misfire. You may also have dirty fuel injectors that need to be cleaned. Have the ECM scanned to see if the misfire code is P0308. This code...

Can I swap a 97 4.3 with a 94 4.3?

Hi there. You can change the engine block, but the cylinder heads will not match up. The cylinder heads for a 94 was made for an intake with a throttle body and injection in the throttle body where the 97...

Ignition tumbler stuck and needs replacement.

The tumblers are part of the ignition switch assembly on these vehicles. This part must be replaced as a unit. This particular part malfunctioning is a common problem on late 1990's Mercedes Benz products. Have a mechanic who is familiar...

Loud idling, clunking, vibrating when stopping, sluggish engine

It sounds like you may have a faulty engine or transmission mount. These mounts are what secures the engine or transmission to the frame of the vehicle. These mounts are made of metal frames with large solid pieces of rubber...

Related articles

How to Monitor Your RPM Gauge to Get the Best Performance Out of Your Car
A car tachometer, or RPM gauge, shows the speed the engine is spinning. Watch your RPM gauge to improve your car's performance and fuel efficiency.
How Long Does a Throttle/Accelerator Pedal Position Sensor Last?
The The throttle/accelerator pedal position sensor detects the position of the accelerator pedal. This information is then transmitted to the vehicle’s computer - the engine control module (ECM). From there, the data is then sent from the computer to the...
A Buyer’s Guide to the 2012 Jaguar XF
The The Jaguar name alone represents luxury, performance and prestige in the world of high-end vehicles. The XF was completely retooled in 2009, a sign of the premium carmaker’s efforts to draw in younger consumers and attract a whole new...