Skip the auto shop - Our mechanics make house calls

Q: low idle around 400 rpms

asked by on

it has this low idle however it does not fluctuate and does not stall. it stays right in place. maybe this is a lack of back pressure? the car is straight piped with true dual pipes and the stock y pipe. can this be a hint to any other major problems?

My car has 193000 miles.
My car has an automatic transmission.

This generation of Lexus GS models has a known issue for this and can often be corrected by cleaning the throttle body. I would also recommend testing the MAF (Mass Air Flow sensor) as well as this can lead to a lower than normal idle depending on the message it is sending to your car’s ECM (Electronic Control Module).

I would also test/check the O2 Sensor (Oxygen Sensor), which is a sensor that monitors the air/fuel content coming from the exhaust.

Based upon these readings, the messages are relayed to your car’s fuel injection system which then tell it what corrections to make.

If you need some help with this, feel free to contact a certified technician, such as one from YourMechanic. They will be able to help perform these checks to diagnose your low idle and help you fix it accordingly.

Was this answer helpful?

Need advice from certified mechanic? Get help now!

Over 1000 mechanics are ready to answer your question.
The statements expressed above are only for informational purposes and should be independently verified. Please see our terms of service for more details

Ask a Mechanic
(100% Free)

Have a car question? Get free advice from our top-rated mechanics.

Ask A Mechanic
Over 10,000 questions answered!

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

Get a quote

What others are asking

Q: Car running rough

When your engine computer sees a problem with a major sensor or sees that an engine is misfiring, the computer will turn on the restricted performance statement with a red or amber light. The problem may be one of several,...

Q: My Lincoln ls 2004 has 9 codes at onece

Hi there. Your vehicle is in a lean mixture state. The fuel system is not supplying enough fuel to the engine. Check the fuel pump to see if its working by putting on a fuel pressure hose on the fuel...

Q: How much money should it cost to replace a drive belt

You may have problems with the tensioner for the belt and not just the belt. Also the power steering should not stop when turning on the a/c. You should first have a mechanic inspect the belt and tensioner along with...

Related articles

What are the Car Pool Rules in Hawaii?
Hawaii is widely regarded as a land of vacation and relaxation, and as such, its scenic roads and routes are far better known than the state’s freeways. But, as with all...
How Much Does a Mechanic Make in Vermont?
Automotive technician jobs in Vermont have an average mechanic salary of $37k, with some mechanics earning a salary of $53k.
P2103 OBD-II Trouble Code: Throttle Actuator Control Motor Circuit High
P2103 means there is a fault with the throttle actuator control motor circuit, likely due to a defective electrical component or part.