When your car runs rough, stumbles or even stalls out while driving, you’ll want to know exactly where to look. With today’s cars controlled by sensors, chances are one of those is to blame. Take the throttle position sensor, for instance.
What can you do to stop car hesitation?
Here’s what automotive specialist Scotty Kilmer did to fix his car hesitation problem:
- Check the vehicle’s diagnostic codes
- Check the throttle position sensor
- Replace and adjust the sensor
Got any questions? Then you’ve come to the right place! Car guru #savagescotty has the answers you’re looking for. Follow along as we get into detail about checking and replacing the throttle position sensor, which should solve most car hesitation problems.
Nipping Car Hesitation in the Bud
Does your car hesitate or stumble when you give it a little throttle? The throttle position sensor may be at fault. Located on the throttle body, this sensor reads the throttle valve position and sends that data to the engine computer or ECM.
The ECM uses that data to determine how much fuel the engine needs to run properly. A bad TPS can send the wrong amount of fuel or send no fuel at all, causing the engine to stumble and hesitate while running.
Scotty Kilmer recommends checking for TPS codes using an OBD-II scan tool. Some scan tools even let you read data from the TPS as you manually move the throttle valve. No data or bad readings from the TPS? These signs point to a bad sensor.
Got an older car like Scotty’s 1988 4Runner that predates OBD-II? Scotty put his car into diagnostic mode by jumping a couple of data terminal pins together. This caused the check engine light to flash the trouble code on the dashboard.
You can look up the appropriate trouble codes for a bad throttle position sensor with a Google Search or thumb through your vehicle’s service manual.
Of course, there’s a complicated way and an easy way to test the TPS. The former involves looking up complex wiring schematics, as Scotty notes at 1:24. The latter? Just unplug the TPS while the engine is running. If it runs better unplugged, then you likely have a bad TPS.
Before you replace the TPS sensor, you might want to see if you can reset the sensor first. Some vehicles let you reset the TPS from the comfort of your own car.
Thinking about poaching a TPS from a junkyard car? Think again. Used and rebuilt sensors can be trouble-prone, according to Kilmer. Head to your local auto parts retailer and buy a brand-new TPS.
It’ll be more reliable and come backed with a warranty.
When it comes time to replace the TPS, unplug it and loosen the two screws holding it in place. These screws can get stuck with age, so Scotty recommends using vice grips to break them loose.
The old sensor will likely have markings to line things up properly. Transfer these marks to the new TPS and use them to line up the new TPS properly during reinstallation.
Once everything’s lined up properly, tighten the screws, plug the connector back in and start the engine. Your car should run noticeably smoother and without any hesitation whatsoever.
Don’t Hesitate to Treat Your Car Right
Knowing how to stop car hesitation is just one of the many tricks and tips you’ll learn when owning a vehicle. Here’s another tip: check out your car’s Vehicle History before you buy and find out more about your vehicle, including top specs and owner reviews.
