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Turbo underboost/limp mode/ Flashing glowplug. Resets upon restarting

Followers

July 9, 20223 yr

My a4 b8 avant goes into limp mode at 2100 rpm, the glow plug light flashes and occasionally the engine management light comes on also. Diagnostic shows underboost fault.

It always resets after restarting the engine.

Is this terminal turbo signs or perhaps just a boost sensor?

Help gratefully received!

July 11, 20223 yr

Author

On 7/9/2022 at 9:50 PM, CCRS said:

My a4 b8 avant goes into limp mode at 2100 rpm, the glow plug light flashes and occasionally the engine management light comes on also. Diagnostic shows underboost fault.

It always resets after restarting the engine.

Is this terminal turbo signs or perhaps just a boost sensor?

Help gratefully received!

FAULT CODE -0299-(Turbo underboost)

Kicks in @ 2100rpm -3000rpm

Power reduction and glow plug lamp flashes

Condition usually resets upon ignition reset..

Sometimes needs OBD to perform fault reset.

POSSIBLE BOOST SENSOR? or TURBO FAULTY?

July 12, 20223 yr

Could be a leaking pipe. Worth considering before changing the turbo.

July 12, 20223 yr

I had this, recently. Must be wear and tear:

2 weeks later...

July 22, 20223 yr

Author

On 7/12/2022 at 12:08 PM, Steve Q said:

Could be a leaking pipe. Worth considering before changing the turbo.

Thanks sir..I appreciate your input. I will investigate that forthwith. 🙂

July 22, 20223 yr

3 hours ago, CCRS said:

Thanks sir..I appreciate your input. I will investigate that forthwith. 🙂

No probs at all 🙂

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Turbo underboost/limp mode/ Flashing glowplug. Resets upon restarting

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