Q: car slows with acceleration

asked by on August 08, 2016

I bought my car 5,000 kilometers ago, and now it has 179,000 kilometers. I replaced the catalytic converter when I bought it. That’s all it needed for the e test. When I first gave the car gas I felt it stutter like it was not getting gas. Then once it got passed that the car picked up. I live in a very hilly area. So lately I’ve been driving the car around in drive. Once I’m cruising at 80 kilometer per hour I turn on the overdrive and the car feels like its running OK. But if I’m going up a hill, and I give it gas the car slows down. If I give it a certain amount of gas with overdrive while around 60 kilometers per hour the car slows down. But with overdrive off it doesn’t have a problem with picking up speed - no slowing down - just the stutter at the start. My check engine light came on last night and this morning. I unplugged the battery for 5 minutes then reconnected it, and the light went away. Do you have any ideas what my problem might be?

The hesitation may be a dirty throttle body or bad throttle position sensor (TPS). If it drives better with OD off, I suggest leaving it off or having it diagnosed and repaired. It won’t hurt anything to leave it off around town although gas mileage may be a bit lower.

Turn overdrive back on for highway cruising. A technician, such as one from YourMechanic, using a scan tool will be able to diagnose it for you. You likely already know that turning off the Check Engine Light just turns off the light and removes helpful info that a technician uses to diagnose the trouble. The issue that caused it to turn on in the first place probably still present. To have all of this taken care of, a certified technician, such as one from YourMechanic can come to your home or office to diagnose your acceleration issue and let you know what should be done.

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


Experienced Mechanic?

Earn up to $70/hr

What others are asking

Car clicks and doesn't start.
Even though it just clicks the battery can still be the problem. Low battery voltage wont have enough juice to turn the starter all the way. The partial engagement will sound like a click. A few other things like bad,...
Car overheated and now won't start
If you drove the car until it quit, it is quite possible that the engine is ruined. Overheating warps the block and heads, and the piston rings lose their spring tension. Every time I have tried to patch together an...
Door will not unlock
Hi. If the door stopped working after it was shut hard, then the door lock actuator rod may have come off of the actuator or the actuator failed. It can also be due to the main switch assembly failing. Both...
Added refrigerant, but no cold air
There are many causes for the AC not to be effective: Low refrigerant is common, but not always the source. The compressor has to turn on and provide the proper circulation. The expansion valve has to create the right amount...
Isit normal for my car to shift between 2000 RPMs and 3000 rpms
Hello, thanks for writing in about your Chrysler Voyager. The shift RPMs will be higher if you are further down on the throttle on faster acceleration. Shifting between 2000 and 3000 is normal.
When on short local runs around town the car does not want to restart! I take a 10 min drive on highway and it starts normal
Hi there, thanks for writing in. You may be having a problem with the purge control valve leaking fumes into the engine when you shut off the car. The fumes will flood the engine and cause hard starts or no...
Car exhaust shake
The exhaust shaking may be related to many things such as loose mounting bolts or potentially a clogged catalytic converter (https://www.yourmechanic.com/services/catalytic-converter-replacement). The popping and cutting out suggests potentially a lean fuel condition which means the car is starving for fuel...
Headlights aim too low when properly adjusted by two mechanics.
Hello. If the headlights are not pointed correctly, then they likely need to be adjusted. Even if a technician has already adjusted them, it may be possible that they were incorrectly pointed. An issue with the mounting may also be...
Clicking sound when turning over.
A starter like any other mechanical and electrical part is subject to failing sometimes for no apparent reason. However, sometimes this is misdiagnosed as well and often times mistaken for something much more simple like a fuse, relay or starter...

Related articles

How Does a Radiator Keep an Engine Cool?
Car radiators cool off your engine and prevent your engine from overheating. Coolant absorbs engine heat and dissipates it through the radiator.
The Most Common Error Codes for Transmission Problems
If your Check Engine Light has come on, there are a number of conditions that could be causing it. Many are related...
Symptoms of a Bad or Failing Evaporator Temperature Sensor (Switch)
Common signs include lack of cold air coming from AC, temperature fluctuations, and the AC compressor not activating.