P0297 explained: P0297 is logged when the vehicle exceeded its programmed speed cap. On most cars this is the manufacturer speed limiter (110-155 mph). Rare in normal driving. If you have not been speeding, suspect a faulty speed sensor or tire-size mismatch.
🎯 Top Causes & Probability
60%
#1 - Most Likely
Actual Overspeed Event
The vehicle was driven above the programmed limit. This is just a log entry - no repair needed, just clear and avoid the limiter.
🔨 Part
$0
👨🔧 Labor
$0-$60
⚡ DIY
Easy
25%
#2 - Check First
Wrong Tire Size or Wheel Diameter
Larger tires than stock cause the PCM to calculate a higher speed than actual. Recalibrate the speedometer with a programmer or scan tool.
🔨 Part
$0-$80
👨🔧 Labor
$50-$150
⚡ DIY
Easy
12%
#3 - Less Common
Faulty Vehicle Speed Sensor
A bad VSS or ABS wheel speed sensor sends a noise spike to the PCM that looks like a 200+ mph reading. Replace the offending sensor.
🔨 Part
$40-$220
👨🔧 Labor
$80-$200
⚡ DIY
Medium
🚗 Most Affected Vehicles
🔧 Step-by-Step Diagnosis
- Clear the code and see if it returns. If it does not, P0297 was a one-time event from actual overspeed.
- If the code returns without exceeding 80 mph, check tire size against the door-jamb sticker.
- Recalibrate speedometer if tire size has changed. A tuner like SuperChips or DiabloSport handles this on most trucks.
- Monitor live VSS data on a scan tool. A glitchy or jumpy reading points to a bad sensor.
- Inspect wheel-speed sensor connectors for corrosion or damage if VSS data is erratic.
- After repair, drive at normal speeds for 20 minutes to confirm the code stays cleared.
❓ Frequently Asked Questions
Is P0297 a serious code?
Not usually. It is more of a log entry. If it does not come back after clearing, ignore it.
What is the speed limiter on my car?
Most US passenger cars cap at 110-130 mph. Trucks often cap at 95-110 mph for tire safety. Performance cars may go to 155 mph or higher.
Will bigger tires set P0297?
They can if your speedo reads much higher than actual. A 35-inch tire on a stock 31-inch setup shows ~13% higher speed than reality.
Can I disable the speed limiter?
Aftermarket tuners can raise or remove the limit. Use only on closed tracks - public-road use is illegal and unsafe with non-rated tires.
Why does P0297 appear if I was not speeding?
A noise spike on the VSS or a momentary sensor glitch makes the PCM think you hit 250 mph for a millisecond. Annoying but not damaging.