Symptom
Only happens over bumps or on rough roads
The warning appears, the engine stumbles or something cuts out as you cross a pothole, a speed hump or a stretch of broken surface, and the smooth roads are fine. Vibration is a diagnostic tool here rather than a coincidence. A connection that is corroded, a pin that has backed out of its housing, or a wire broken inside insulation that still looks perfect will all hold together until something shakes them — which is why the fault follows the road rather than the engine. Say which part of which road, because a fault that repeats at the same place every time is one somebody can go and reproduce.
Also described as: happens over bumps, on rough roads, when i hit a pothole, over speed bumps, only on bad roads, vibration makes it happen, روی دست انداز اتفاق میافتد, در جاده خراب, solo en baches, pasa en carretera mala, al pasar badenes, صوت خبط على المطبات, خبط من قدام على المطبات, فقط على المطبات, على الطرق الوعرة, عند المرور على الحفر
Some causes mean you should stop driving
6 of the 64 codes that produce this symptom indicate a fault where continuing to drive risks damage or is unsafe. If the symptom is sudden or severe, treat it as one of those until a scan says otherwise.
What this usually means
Vibration is a diagnostic tool here rather than a coincidence. A connection that is corroded, a pin that has backed out of its housing, or a wire broken inside insulation that still looks perfect will all hold together until something shakes them — which is why the fault follows the road rather than the engine.
That is a genuinely narrow finding. It rules out most of what a scan tool would suggest, because a sensor does not care about road surface and a control strategy does not change over a pothole. What does change is mechanical: harness sections that flex, connectors that move, and anything mounted on something that moves relative to something else.
The wiggle test is this fault reproduced deliberately, and it is the single most productive technique available. Flex the harness and connectors by hand while watching live data, or a meter recording minimum and maximum so a momentary open is captured rather than missed. Some scan tools have a dedicated wiggle mode that alerts on a dropout, which lets you watch your hands instead of the screen.
Work where movement is greatest: across the engine's own movement on its mountings, at the steering column, into the doors, along the suspension, and anywhere a harness passes a bracket or an edge. A wire chafed through inside intact insulation is invisible and is found only by moving it.
And say which part of which road. A fault that repeats at the same place every time is one somebody can go and reproduce — which converts an intermittent into a fault with an address.
Working through it
| What you find | Likely cause | How to confirm it | What fixes it |
|---|---|---|---|
| Warning or cut-out that follows road surface, not engine load | A connection that only holds when still — corrosion, a backed-out pin, or a wire broken inside its insulation | Wiggle-test the harness and connectors while monitoring live data, or a meter recording minimum and maximum so a momentary open is caught. | Repair the connection and secure the harness clear of what it moves against. |
| Repeats at the same place on the same road | A specific mechanical excitation — the same bump, the same frequency, the same section of harness | Go there and reproduce it with a logger running. This converts an intermittent into a fault with an address. | Repair what the log implicates. Repeatability at one location is the most useful thing a driver can report here. |
| Fault worst where the harness crosses the engine's movement | Chafing at a bracket or edge, or a loom stretched by a collapsed engine mounting | Inspect the harness where it passes brackets and edges, and check the mountings — a failed mounting lets the engine move further than the loom allows. | Repair the harness, sleeve it, and renew the failed mounting. Repairing the wire alone lets it happen again. |
| Electrical fault confined to doors or the tailgate | The flexible loom in the door aperture — the most-flexed wiring on the vehicle | Open and close the door slowly while monitoring the affected circuit. The break is usually in the rubber boot between body and door. | Repair or renew the section inside the boot, with enough slack that it flexes rather than stretches. |
| Noise or clunk rather than an electrical fault | Suspension, exhaust mountings or a heat shield rather than wiring | Separate the two: a noise over bumps is mechanical, a warning over bumps is electrical. Bounce-test at each corner and check heat shields by hand. | Repair the mechanical fault. The corpus does not carry codes for a loose heat shield, which is why it is worth naming here. |
| Also happens in wet weather | A connector failing on two counts — corroded and mechanically marginal | Combine the tests: spray, then wiggle, while monitoring. Either alone may miss it. | Renew the connector rather than cleaning it. |
-
Warning or cut-out that follows road surface, not engine load
- Likely cause
- A connection that only holds when still — corrosion, a backed-out pin, or a wire broken inside its insulation
- How to confirm it
- Wiggle-test the harness and connectors while monitoring live data, or a meter recording minimum and maximum so a momentary open is caught.
- What fixes it
- Repair the connection and secure the harness clear of what it moves against.
-
Repeats at the same place on the same road
- Likely cause
- A specific mechanical excitation — the same bump, the same frequency, the same section of harness
- How to confirm it
- Go there and reproduce it with a logger running. This converts an intermittent into a fault with an address.
- What fixes it
- Repair what the log implicates. Repeatability at one location is the most useful thing a driver can report here.
-
Fault worst where the harness crosses the engine's movement
- Likely cause
- Chafing at a bracket or edge, or a loom stretched by a collapsed engine mounting
- How to confirm it
- Inspect the harness where it passes brackets and edges, and check the mountings — a failed mounting lets the engine move further than the loom allows.
- What fixes it
- Repair the harness, sleeve it, and renew the failed mounting. Repairing the wire alone lets it happen again.
-
Electrical fault confined to doors or the tailgate
- Likely cause
- The flexible loom in the door aperture — the most-flexed wiring on the vehicle
- How to confirm it
- Open and close the door slowly while monitoring the affected circuit. The break is usually in the rubber boot between body and door.
- What fixes it
- Repair or renew the section inside the boot, with enough slack that it flexes rather than stretches.
-
Noise or clunk rather than an electrical fault
- Likely cause
- Suspension, exhaust mountings or a heat shield rather than wiring
- How to confirm it
- Separate the two: a noise over bumps is mechanical, a warning over bumps is electrical. Bounce-test at each corner and check heat shields by hand.
- What fixes it
- Repair the mechanical fault. The corpus does not carry codes for a loose heat shield, which is why it is worth naming here.
-
Also happens in wet weather
- Likely cause
- A connector failing on two counts — corroded and mechanically marginal
- How to confirm it
- Combine the tests: spray, then wiggle, while monitoring. Either alone may miss it.
- What fixes it
- Renew the connector rather than cleaning it.
Codes that produce this symptom (64)
Listed with the codes that most typically present this way first — the likeliest place to start.
- C0031 Left Front Wheel Speed Sensor Typical of this code Moderate
- C0034 Right Front Wheel Speed Sensor Typical of this code Moderate
- C0037 Left Rear Wheel Speed Sensor Typical of this code Moderate
- C003A Right Rear Wheel Speed Sensor Typical of this code Moderate
- C003D Rear Wheel Speed Sensor Typical of this code Moderate
- P0074 Ambient Air Temperature Sensor Circuit A Intermittent/Erratic Typical of this code Low
- P0104 Mass or Volume Air Flow Sensor A Circuit Intermittent Typical of this code Moderate
- P0317 Rough Road Hardware Not Present Typical of this code Low
- P0318 Rough Road Sensor A Signal Circuit Typical of this code Low
- P0319 Rough Road Sensor B Signal Circuit Typical of this code Low
- P0339 Crankshaft Position Sensor A Circuit Intermittent Typical of this code Stop driving Critical
- P0344 Camshaft Position Sensor A Circuit Intermittent Bank 1 or Single Sensor Typical of this code Stop driving High
- P0369 Camshaft Position Sensor B Circuit Intermittent — Bank 1 Typical of this code Stop driving High
- P0389 Crankshaft Position Sensor B Circuit Intermittent Typical of this code Stop driving High
- P0454 Evaporative Emission System Pressure Sensor/Switch A Circuit Intermittent Typical of this code Low
- P0464 Fuel Level Sensor A Circuit Intermittent Typical of this code Low
- P0503 Vehicle Speed Sensor A Circuit Intermittent/Erratic/High Typical of this code Moderate
- P0518 Idle Air Control Circuit Intermittent Typical of this code Low
- P0709 Transmission Range Sensor A Circuit Intermittent Typical of this code Moderate
- P0718 Input/Turbine Shaft Speed Sensor A Circuit Intermittent Typical of this code High
- P0723 Output Shaft Speed Sensor Circuit Intermittent Typical of this code High
- P0754 Shift Solenoid A Intermittent Typical of this code High
- P0759 Shift Solenoid B Intermittent Typical of this code High
- P0764 Shift Solenoid C Intermittent Typical of this code High
- P0794 Intermediate Shaft Speed Sensor A Circuit Intermittent Typical of this code High
Information, not instruction
CarGeek is a reference, not a service manual. Its pages are written from public sources and from what other people have found, never from a manufacturer's own service information, so they can be wrong or incomplete for your particular vehicle. Some of what they describe carries real risk: high voltage, fuel under pressure, stored energy, hot and moving parts.
Have anything you intend to act on checked by a trained person against the manufacturer's own procedure for your vehicle. Nothing here replaces that procedure.
Others with this symptom
Be the first to write this up
Nothing posted about this yet. Whatever you found is worth writing down — even a dead end saves someone the same afternoon.
What makes one worth reading:
- The car — make, model, year and engine. The same fault behaves differently on each.
- What you measured, not only what you replaced.
- What actually fixed it — or that nothing did, which is worth knowing too.
Sign in or create an account to add what you found about Only happens over bumps or on rough roads.