Skip the auto shop - Our mechanics make house calls

Q: My car is jerking from 2nd to 3rd gear and downshifts. Will jerk a little

asked by on

After a little driving my car will jerk from 2nd to 3rd gear and downshift. It will jerk a little too. Sometimes it will smooth out on the highway and sometimes it won't do it at all. They hooked it up to the computer and got a code for P0661 but I can't seem to understand why that would affect it. My transmission was rebuilt 45000 miles ago and it's been on and off like this for a year and a half and I already performed a fluid change and filter. Any help would be greatly appreciated.

My car has 230000 miles.
My car has an automatic transmission.

A: Hi, thanks for writing in. Your car has wha...

Hi, thanks for writing in. Your car has what is called a secondary shifter valve or solenoid valve that is operated or directed by the PCM (Powertrain Control Module) which is what controls the drivetrain and transmission. Code P0661 is related to this and is what is causing the jerking between shifts. This can happen when the solenoid itself is bad or faulty or simply due to a poor connection or shorted harness. If you would like help, consider having an expert automotive technician from YourMechanic come to your home or office to inspect and diagnose this issue for you, and make or suggest any repairs as needed.

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・Save up to 30%

Get a quote

What others are asking

Q: How long does it take to replace the compressor bracket

Once the compressor is removed from the bracket, then there is only a couple of bolts that hold the bracket to the engine block. Make sure the compressor rear bracket is tightened or the new bracket will break. The bracket...

Q: Transmission leak

Hi. Automatic transmissions operate using hydraulic pressure. Without the proper fluid level, the transmission can't build pressure and won't operate properly. Locating and fixing the transmission leak may solve your problem. Have a technician inspect the transmission leak and repair...

Q: I have weak battery that caused me to have to be jumped every couple times started. Now it wont turn over at all. Is it starter

Hello. You are correct. There is a very strong chance that the starter has gone bad. If the solenoid is serviceable and you want to attempt to change only that, and you may be able to prolong the life of...

Related articles

What Causes Hoses to Leak?
While the largest part of your engine is mechanical, hydraulics plays a significant role. You’ll find fluids at work in a number of different areas. Your car's fluids include: Engine oil Transmission...
How Long Does a Distributor O Ring Last?
The distributor is part of the ignition system in your vehicle and its purpose is to route high voltage from the ignition coil to the spark plug. The spark plug then...
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.