Intermittent wiring or connector issue (35% likelihood): A loose connection, chafed wire, or corroded pin in the TCC solenoid circuit can cause intermittent electrical contact, especially as the vehicle vibrates and heats up during driving. TCC solenoid beginning to fail (30% likelihood): A solenoid that is starting to wear out may work intermittently, engaging and disengaging the converter clutch erratically as its internal components degrade. Contaminated transmission fluid (15% likelihood): Debris in the fluid can intermittently obstruct the solenoid or its hydraulic passages, causing inconsistent TCC operation. Valve body sticking intermittently (12% likelihood): Temperature-sensitive sticking in the valve body can cause the TCC apply pressure to fluctuate, resulting in intermittent lockup behavior. Internal torque converter wear (8% likelihood): Early-stage wear of the converter clutch material can cause intermittent slippage during lockup.

How much does it cost to fix P0744?

DIY repair typically costs $15–$120 for parts. Professional repair runs $200–$900 including parts and labor.

P0744

Powertrain

Moderate

Torque Converter Clutch Circuit Intermittent

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P0744 indicates that the torque converter clutch circuit is experiencing intermittent problems. The PCM has detected that the TCC is engaging and disengaging erratically or that the electrical signal to the solenoid is cutting in and out. This is the most frustrating of the TCC codes because the problem comes and goes, making it harder to diagnose.

You'll likely notice an inconsistent shudder or vibration during highway driving, as the torque converter clutch repeatedly locks and unlocks. Fuel economy may fluctuate as the lockup comes and goes. The Check Engine light itself may be intermittent — illuminating for a while and then turning off, only to return later.

Intermittent electrical problems are notoriously difficult to diagnose because the fault may not be present when the vehicle is being tested. A thorough inspection of the wiring harness and connectors in the TCC circuit is the best starting point. Look for loose pins, corroded terminals, or chafed wires near heat sources. A transmission fluid service is also worthwhile, as debris in the fluid can cause intermittent solenoid issues. If the problem persists after addressing wiring and fluid, the solenoid itself is likely failing and should be replaced.

Severity

Moderate — Address SoonThis Week

Symptoms

•Intermittent shudder or vibration at highway speeds
•Fuel economy fluctuates noticeably
•Check Engine light may come and go
•Occasional hesitation or surge during steady cruising
•Torque converter lockup feels inconsistent

Likely Causes

Intermittent wiring or connector issue35%

A loose connection, chafed wire, or corroded pin in the TCC solenoid circuit can cause intermittent electrical contact, especially as the vehicle vibrates and heats up during driving.

TCC solenoid beginning to fail30%

A solenoid that is starting to wear out may work intermittently, engaging and disengaging the converter clutch erratically as its internal components degrade.

Contaminated transmission fluid15%

Debris in the fluid can intermittently obstruct the solenoid or its hydraulic passages, causing inconsistent TCC operation.

Valve body sticking intermittently12%

Temperature-sensitive sticking in the valve body can cause the TCC apply pressure to fluctuate, resulting in intermittent lockup behavior.

Internal torque converter wear8%

Early-stage wear of the converter clutch material can cause intermittent slippage during lockup.