Skoda Octavia engine prob

[JapFan]

Hi guys,

Have now for some time the error 16555 System to lean. When erased after 2 days the failure is back again. Engine code BFQ.

Any sugestions?

[oldford]

Well, the engine is not getting enough fuel or a signal makes the ecu believe that is too lean.
Usual suspects: Maf-senor (low signal), leaks in the intake system or a leak in the exhaust system near the Oxygen sensor.
Post Oxygen sensor values with idle and 3000 rpm.
Check intake system and exhaust manifold for leaks.

[JapFan]

Hello thanks for you response I have checked Intake system. Then also exhaust system. But nothing helped. Then in desperate move I changed the oxygen sensor before cat and this resolved the issue. Its funny because most of the post I have read on every possible web site everybody changed oxygen sensor first thing and it didnt helped.

[cactikid]

was that a five wire one as they go a lot and we can double check on scope for wave and percentage during test most are down at 5% working.