Q: Q: High idle problem.

asked by on

When I start my truck my idle stays at 1500 and won't go down
My car has a manual transmission.

This may be a sign of a vacuum leak. A vacuum leak can be one of the most frustrating and difficult problems to diagnose. High idle speed is a common sign and stalling is another. Confirmation of an engine vacuum leak can be a very loud hissing sound coming from the engine area. When a vacuum leak is present in an engine, this causes an excessive imbalance in the air/fuel ratio which creates a loss of power and causes the motor to run at a much higher RPM as a result of the increased oxygen present in the fuel charge being injected into the motor. I would recommend having an expert from YourMechanic come to your location to diagnose your vacuum leak as these can be very difficult and time consuming to trace.

Was this answer helpful?
The statements expressed above are only for informational purposes and should be independently verified. Please see our terms of service for more details
  1. Home
  2. Questions
  3. Q: High idle problem.

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: Quick my mechanic told me I need to change my motor mounts he listed front rear

You have a total of 4 mounts. There is one front engine mount and two transaxle mounts then there is a torque mount on top front.

Q: Manual transmission makes noises - 1994 Nissan D21

Hello. It sounds like you have a gear, bearing, bushing, or other rotating component issue caused by wear. At that mileage, really the thing to do is just simply rebuild the transmission which is not particularly difficult since it is...

Q: Problem with shifting positions

It may very well be that your vehicle has a problem that is causing reduced power output. Some such things could be: Faulty fuel pump Faulty oxygen sensor Vacuum leak When any of these occur, the...

Related articles

P0052 OBD-II Trouble Code: HO2S Heater Control Circuit High (Bank 2 Sensor 1)
P0052 code definition HO2S Heater Control Circuit High (Bank 2 Sensor 1) What the...
P0240 OBD-II Trouble Code: Turbocharger Boost Sensor B Circuit Range/Performance
P0240 code definition Turbocharger Boost Sensor B Circuit Range/Performance What the P0240 code means P0240 is an OBD-II generic code triggered when the Engine Control Module (ECM) detects the intake boost...
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.