Skip the auto shop - Our mechanics make house calls

Q: How can I be sure i am having a Throttle Position Sensor issue?

asked by on

When I come to a stop and then pull out my ML320 does not respond to the throttle. Although it will begin to slowly move and pick up speed but it still does not respond to acceleration attempts. Finally, after numerous attempts, I shut the ignition off and more often than not the problem disappears and it resumes normally to giving it gas.

My car has 135000 miles.
My car has an automatic transmission.

Typically a throttle position sensor (TPS) is tested using a multimeter. The specs to compare against are published in the Factory Service Manual. As long as the TPS tests within the range of published values, and does not display intermittent or sticky operation, you can assume it is good. There are other components within the air induction system that should be considered such as any mass airflow sensor, idle air control valve and so forth. Faulty EGR systems, and fuel system deficiencies, can be a part contributor to the acceleration problem you are describing. In addition, the fault may not be component related but rather wiring or ground related. Of course, an attempt should be made to see if any Diagnostic Trouble Codes have been set in the PCM which codes might provide clues to the origin of the fault. If you desire that this problem be diagnosed by a certified Mechanic, dispatched by YourMechanic right to your location, please request a poor acceleration diagnostic and the responding mechanic will get this resolved for you. If you have further questions or concerns, do not hesitate to re-contact YourMechanic.

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!
  1. Home
  2. Questions
  3. How can I be sure i am having a Throttle Position Sensor issue?

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: Error code p1516 with check engine and reduced engine power unable to drive over 30mph car is revving up put no power

The code P1516 is is for the throttle position sensor. It looks like the car's computer is putting the engine in "failsafe mode" to prevent the car from being driven much further. A technician would need to examine the system...

Q: I had to change output the speed sensor, but my car still drive in 5 high. What do I need to do?

Hi there. Since you have replaced the speed sensor and your vehicle is still giving you the engine light code P0720 for the speed sensor circuit malfunction, then you would need to check the circuits from the speed sensor to...

Q: Car does not move

Hi there. There are multiple components that could be damaged; causing your MB to not accelerate. Some of the possible issues include shifter linkage problems, shift sensors or internal transmission components that are damaged and require replacement or service. It's...

Related articles

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...
Rules of the Road For Iowa Drivers
Driving on the roads requires knowledge of the rules, many of which are based on common sense and courtesy. However, even though you know the rules in...
P2428 OBD-II Trouble Code: Exhaust Gas Temperature Too High Bank 1
P2428 code definition A P2428 trouble code signifies that the PCM has detected a problem in the exhaust gas temperature sensor circuit in bank 1, which subsequently contains the number one...