Tatra T87 C3378 Engine Trouble Code
What is Tatra T87 C3378?
The Tatra T87 C3378 check-engine light can indicate issues ranging from minor (loose gas cap) to serious (catalytic converter failure). Professional diagnostic scanning at a dealer or shop will identify the exact cause and required repairs.
C3378 on the Tatra T87
Diesel variants of the Tatra T87 trigger C3378 most often due to swirl flap actuator failure. The plastic actuator arm breaks and the flap defaults to the closed position, causing severe intake restriction and the associated fault flag.
Code Information
| Code Type: | OBD-II Chassis (C) Trouble Code |
| System: | Chassis |
| Vehicle: | Tatra T87 |
| Brand: | Tatra |
| Model: | T87 |
| Code: | C3378 |
C3378 Tatra T87 Symptoms
Check Engine Light
Illuminated Tatra T87 dashboard warning
Engine Stalling
Engine stops unexpectedly or misfires
Performance Issues
Reduced power or acceleration on the Tatra T87
Starting Problems
Difficulty starting the engine
Poor Fuel Economy
Increased fuel consumption on the Tatra T87
Increased Emissions
Failed emissions test due to C3378
C3378 Code Structure
Understanding what each digit means in the C3378 chassis trouble code:
| C | 3 | 3 | 7 | 8 |
|---|---|---|---|---|
| Chassis Code | Ignition System Or Misfire | Throttle/Pedal Position Sensor/Switch A Circuit Intermittent | Cylinder 10 Contribution/Balance Fault | Clutch Position Sensor Circuit Malfunction |
How to Fix Tatra T87 C3378
Diagnostic Steps:
Check if fuel pump primes when key is turned to ON. Measure fuel pressure and verify bright white-blue spark at all plugs. Also verify mechanical timing alignment.
Repair Solution:
Excessive air inflow may result from vacuum leaks, dirty sensors, or EGR valves not closing properly. Insufficient fuel can stem from dirty injectors, clogged filters, weak fuel pump, or leaking pressure regulator.
Technical Notes:
C3378 DTCs can be triggered by upstream issues. For example, a dirty MAF sensor may cause incorrect fuel-trim adjustments, leading oxygen sensors to report mixture problems. Address root causes first.
Tatra T87 C3378 Repair Cost
Torque converter clutch solenoid replacement on the Tatra T87 — relevant for owners who tow regularly — costs $280–$480. A full transmission fluid change ($120–$160) at the same service is recommended because contaminated fluid accelerates solenoid wear.
C3378 Description
C3378 engine trouble code is related to Clutch Position Sensor Circuit Malfunction.
Main Cause
The primary reason for C3378 OBD-II Engine Trouble Code is: Throttle/Pedal Position Sensor/Switch A Circuit Intermittent.
Common C3378 Misdiagnosis on the Tatra T87
The Tatra T87 purge valve for the EVAP system is located in an area prone to heat damage. It is often overlooked in favour of replacing the carbon canister ($120–$200) when the valve itself ($25–$50) is the failed component for C3378.
DIY Repair Guide: C3378 on Tatra T87
The Tatra T87 EVAP purge solenoid valve is accessible without lifting the vehicle — it is mounted on the intake manifold and secured by a single bolt and a vacuum hose clip. DIY replacement is rated 1/5 difficulty and takes approximately 20 minutes.
Preventing C3378 on the Tatra T87
The Tatra T87 EVAP system requires the fuel tank breather hoses to be flexible and crack-free. A visual inspection at every oil change prevents the slow vacuum leak that triggers C3378 without any drivability symptom.
Frequently Asked Questions — Tatra T87 C3378
A: If your Tatra T87 is within the factory powertrain warranty period (typically 3–5 years or 60,000–100,000 miles depending on region and generation), C3378 repairs caused by component defects should be covered. Bring your service history to the dealer appointment.