Skip the auto shop - Our mechanics make house calls

Q: My speedometer is going back and fourth and drops to zero while driving but, my rpm gauge is fine.

asked by on

I was driving the other day and my speedometer started moving back and fourth. The rpm gauge is fine everything else is fine on the panel except for that speed gauge. I tested my car it pulled a code up p0335 I do have a wire harnes clip that is bad the wires look like they aren't fully connected I looked up where it goes to it said it went to the crank sensor. I just want to know what I should maybe look for first. Thank you for your help.

My car has 240000 miles.
My car has an automatic transmission.

A: Hello. The crankshaft position sensor will ...

Hello. The crankshaft position sensor will not cause a fluctuation in the speedometer gauge. It can affect the rpm gauge, but not the speedometer. If the speedometer is acting like this then most of the time this is caused by a failure in the vehicle speed sensor. When this sensor or the connection at the sensor fails then this will happen. If you are planning on having this speedometer issue repaired, consider YourMechanic, as a certified mechanic can come to your home or office to diagnose and repair this.

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

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: My water pump just dumped all its fluid. Is it safe to drive my truck if I fill it back up with water without a new pump?

Anytime there is no or low coolant in a vehicle, it can be very harmful to the engine. Low coolant can cause a seized engine or a blown head gasket. It is recommended that you have the vehicle towed...

Q: VSC and Traction control lights on after wheel alignment. Unable to reset/recalibrate

A faulted sensor like the steering angle sensor can cause these systems to malfunction. A steering angle reset is required with an alignment on these vehicles and involves a procedure that includes disconnecting the battery. If you'd like a fresh...

Q: Starting problem, engine revs at low RPM in drive - 1999 Chevrolet C3500

It sounds like the Idle Air Control valve is gunked up. It may be possible to clean it, or it might have to be replaced. A YourMechanic professional can help to diagnose the stalling issue and replace the idle air...

Related articles

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...
How Long Does a Heater Control Valve Last?
Keeping the right amount of coolant in a car is essential in keeping the engine at the right temperature. Failing to have the right amount of coolant or even bad elements...
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...