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P2270 Oxygen Sensor Fault

12K views 10 replies 4 participants last post by  mike1967  
#1 ·
Hi all,

Hoping that someone can point me in the right direction with the following fault code;

P2270 Heated Oxygen Sensor HO2S 2, Bank 1 - Signal Stuck Lean

276799
Is this the Sensor by the Manifold in the engine bay, or the Sensor on the rear box ?

Are they easy to access / change ?

Idle is also a bit lumpy at the moment, guessing it’s related to this faulty Sensor ?

Many Thanks

Kernow Lad
 
Discussion starter · #3 ·
Cheers Scudder,

Have cleared the code, but haven't replaced the sensor yet (I've got one, but thought I'd chance the MOT) ..

Anyway it failed today, on emissions ? Not surprised though .. My mechanic mate thinks it might be the first sensor causing the problem based on these failures ..

276941
 
Discussion starter · #5 ·
Hmm - I can honestly say there is no smoke, or smell of oil, or oil being consumed at all ..

It's an R56 engine if it helps ?

Does smell a bit rich at times, like a choke is stuck on, and idle tickover is a bit lumpy but no other symptoms
 
Discussion starter · #8 ·
So, after various diagnostics and live readings - it appears that there is a distinct lack of output pressure (mechanic says it should be something like 20, but it's only giving out 5) ..

They've seen it before on this engine, and they think it's the timing chain / and possibly the sprocket jumping due to missing teeth ..

So cheers mike1967 ?