TVA OFF

TVA on diesel engines has three basics functions, prevents the engine from going on an "overrevving", "calms" the engine when shutting down and prevents anything from entering the intake manifold when the engine is turned off. Its first function is important when the engine is in a state

(usually due to a broken turbine) in which it sucks engine oil into the cylinders and make "overrevving", then by shutting down the engine, the TVA closes and interrupts the flow of oil and air into the engine.

The second function is important in the daily shutdown of the engine, because turning the shut-off key closes the valve and soothes the engine from shaking and vibration because it stops much faster when the valve is closed. The third item is important when maintaining the engine, transport, replacement

… The problem with TVA usually occurs by shrinking

the soot as with the EGR valve, which leads to mechanical blocking and later to electronic failure of the valve itself.

▶️The most common symptoms of defective VAT are: 

✅️Restless engine idling 

✅️The clicking sound coming from the TVA 

✅️Lower engine power with excessive exhaust fumes 

✅️ Limiting engine power (safe mode, limp mode) 

✅️Appearance of MIL lamp (check engine lamp) 

✅️Cessation of DPF regeneration and clogging of the DPF 

▶️There are several ways to solve the TVA problem: 

✅️removal and cleaning - if the problem is in the mechanical clogging it can help but if the problem is of an electronic nature in the valve electronics, cleaning will not help 

✅️used TVA - the rule applies as for any used item; it can take a long time and may break down again the next day 

✅️new TVA - this will certainly solve the problem of the next 20,000 km approximately how much the TVA needs to be re-heated after replacement, but the problem is also the price because the new TVA is not cheap 

✅️ deregistering TVA from the motor computer –

 the only permanent solution to all the problems that TVA can cause, but also the protective functions that TVA has will be excluded, so this OFF carries certain risks. 

Shutting down the engine will not be as quiet as when the TVA is running so this TVA off carries a lot of problems and is not as 

recommended as other possible OFFs of other things on the engine sunny one thyme with correct and quality OFF procedure, the engine will work completely correctly without any lights, 

errors or limp modes. Also, the DPF will continue to perform regeneration at the prescribed intervals. 

During the technical inspection, it will not be possible to notice the check-out of the TVA and the vehicle will pass all ECO tests.