Skip the auto shop - Our mechanics make house calls

Symptoms of a Bad or Failing Speed Timing Sensor

speed timing sensor

Bad or Failing Speed Timing Sensor Inspection

by a top-rated mechanic at your home or office

One of the most important settings your engine requires is proper ignition timing. Back in the "old days", manual systems like the distributor, points and coil would work together to mechanically control the ignition timing for engines. If you wanted to change the ignition timing, a mechanic would have to physically adjust the distributor and set it with the use of the timing light. Things have changed in recent years, as today's modern engines utilize multiple electronic devices to monitor and adjust ignition timing on the fly. One of these components is the speed timing sensor.

The speed timing sensor is mounted to the engine block and is a magnetic coil. It reads the teeth on the crankshaft as it revolves to determine the speed of the rotation. It then sends that information to the engine control module to report how the engine is performing. From there, the settings are adjusted to enhance the performance of the engine.

The ability to monitor engine efficiency in "real time" allows a vehicle to save fuel, operate as efficient as possible and can extend parts life. However, like any other sensor, it is prone to damage or failing and will display a few warning signs that a potential problem exists. Noted below are a few of the common symptoms of a worn out or failing speed timing sensor.

HAVE SYMPTOMS OF CAR TROUBLE?
Get an $80 diagnostic
by a top-rated mechanic at your home or office.

Get a quote · Book an Appointment · Our expert mechanics come to you.

1. Transmission has difficulty shifting

One of the main jobs of the speed timing sensor is to monitor the engine RPM and send that information to the ECU which tells the transmission it's time to shift into a higher or lower gear. If the speed timing sensor is failing or sending inaccurate data, the engine will rev higher before the transmission shifts into a higher gear. You'll notice this issue if you're accelerating to highway speed and the transmission seems to take a long time to shift into the higher gear. If you notice this symptom, it's best to contact a local ASE certified mechanic as soon as possible, so they can replace the speed timing sensor if that is the source of the problem.

2. Check Engine Light comes on

The check engine light is typically the first indication that a problem with an engine sensor exists. Anytime a fuel, electronic or safety sensor is faulty, or sending inaccurate information to the vehicle’s ECU, the Check Engine Light will illuminate on the dashboard. Although many motorists tend to ignore the Check Engine Light, in this case, it could cause significant damage to your engine, transmission and entire drive-train if the speed timing sensor is the reason for the light.

Anytime your Check Engine Light comes on, you should contact a mechanic who will arrive with a diagnostic scanner that can download error codes from the computer and help them diagnose the precise problem.

HAVE SYMPTOMS OF CAR TROUBLE?
Get your car fixed at your home or office.

Get a quote · Book an Appointment · Our expert mechanics come to you.

3. Vehicle does not start

When the speed timing sensor is broken, it will not be able to send a signal to the vehicle’s onboard computer. This will shut down the ignition system and you will be unable to start the car. This is due to the fact that the onboard computer will be unable to calculate the engine speed. This causes the fuel system and ignition system to shut off, as improper ignition timing could cause catastrophic engine failure. If your vehicle does not start, contact a certified mechanic to determine why this is happening.

4. Loss of engine power

Another common symptom of a broken speed timing sensor is when the engine seems to lose power. This will be attributed to the engine’s inability to adjust timing as the vehicle drives down the road. The normal default of the engine computer is to reduce engine timing or (retard the timing) which takes power away. When you notice the car, truck or SUV is running sluggish, you should contact a local mechanic to road test and diagnose why this is happening. There are several issues that might be causing this warning sign, so it's best to have a mechanic pinpoint the exact reason.

A problem with the speed timing sensor is very rare, but when it goes bad, it typically triggers a safety setting in the vehicle's computer to ensure further damage does not occur. Anytime you notice any of the above warning signs, make sure to contact a local ASE certified mechanic so they can properly diagnose what's wrong and replace the speed timing sensor if needed.

The statements expressed above are only for informational purposes and should be independently verified. Please see our terms of service for more details
Still not sure about your car's issue?
Diagnose your car
What kind of issue are you experiencing?
Brakes are squeaking
Car is not starting
Car is overheating
Car is shaking (vibrating)
Fluids are leaking
Heating and A/C
Smoke or steam is coming out of the car
Warning light is on
Icon-warranty_badge-02

Skip the repair shop, our top-rated mechanics come to you.

At your home or office

Choose from 600+ repair, maintenance & diagnostic services. Our top-rated mechanics bring all parts & tools to your location.

Fair & transparent pricing

See labor & parts costs upfront, so you can book with confidence.

12-month, 12,000-mile warranty

Our services are backed by a 12-month, 12,000-mile warranty for your peace of mind.

Get A Quote

Need Help With Your Car?

Our certified mobile mechanics make house calls in over 2,000 U.S. cities. Fast, free online quotes for your car repair.

GET A QUOTE

More related articles

How Long Does a Vacuum Brake Booster Check Valve Last?
The braking system on your car requires a lot of pressure. The vacuum booster is one of the main sources of this pressure. This booster will take the pressure that...
Symptoms of a Bad or Failing Flexible Clutch Hose
Common signs include difficulty shifting, low clutch fluid, and feeling no resistance at the clutch pedal.
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...


Related questions

Q: I have a bad knock sensor. Is it worth replacing?

Hello. Yes, you are correct - the P0325 is indicative of a failed knock sensor (or the knock sensor wiring). I think it is a rare circumstance where you would not want to make this repair. It is straightforward and...

Q: Does the starter require a shim on a 2009 ford fusion

Hello, thanks for writing in about your Ford Fusion. I have never seen Ford use any shims on their starters. Only GM vehicles use them that I know of. I would recommend having the starter drive and engine flywheel checked...

Q: Flashing lighting bolt and traction light on, truck will not go over 2000rpm

The lightning bolt light in the Dodge Durango is related to the throttle body. The throttle body is what is responsible for delivery of fuel to your car's engine. This can come on for a couple of different reasons. Commonly,...