Misfire Oxygen Sensor Fault?

[Omar]

Lovely morning so we decided on a drive out to the Cotswolds for breakfast at the The Classic Motor Hub, but we didn’t get there.
When I put the car away couple of weeks ago it was running perfectly, this morning on starting I thought it sounded a bit lumpy, anyway off we go a good run will do it good.....

Nice and gentle to warm up but still didn’t seem right, joined the M50 and under acceleration the engine light flashed but as soon as you eased back to cruise it went out. Persevered in the hope it would clear up, but aside from occasionally running well it was mostly not happy, sounded like one cylinder dropping out.

Turned around, got home, connected the odb and pulled the following:

P0152, 02 sensor circuit, high voltage bank 2 sensor 1
P0305 cylinder 5 misfire
P0307 cylinder 7 misfire
P0308 cylinder 8 misfire
P0300 Random multiple cylinder misfire

Battery is fully charged and a use a trickle charger to keep it in good health.
1/2 tank of fuel
Ran perfectly last time out, it’s literaly just been parked in the garage.

Bit of googling suggests oxygen sensor fault, or could it be something else, I’m sure someone here will have encountered this before suspect it going to need a trip to someone who knows how to trouble shoot.

Car still starts fine but for sure it’s poorly!

 

[CatmanV2]

Lambda fault would be my guess. Misfire on the same bank, as well as lambda fault recorded.

C

 

[conaero]

Does indeed look like the front Lambda on bank 2. Before you replace it get underneath and check the plug and the wiring where it goes up by the radiator, seen several wires break at this point and replacing the lambda does not fix it.

 

[Omar]

Just thought I would close together loop on this, after replacing the Lambda sensor and checking the wiring (thanks conaero) it was still poorly, had the car collected this week and taken up to Migliore in Bromsgrove.

A spark plug.... well I recon I’m now initiated, had all 8 replaced, and was running sweet coming home, despite the gridlock on the M5... very pleased it was that simple, and frustrated too

Now looking forward to some pleasure miles in the sun..

 

[sinver]

Just thought I would close together loop on this, after replacing the Lambda sensor and checking the wiring (thanks conaero) it was still poorly, had the car collected this week and taken up to Migliore in Bromsgrove.

A spark plug.... well I recon I’m now initiated, had all 8 replaced, and was running sweet coming home, despite the gridlock on the M5... very pleased it was that simple, and frustrated too

Now looking forward to some pleasure miles in the sun..

Dear sir,

I have recently purchased a Maserati Coupe 2005 MY

I have the same problem but wihout this DTC :
P0152, 02 sensor circuit, high voltage bank 2 sensor 1

This DTCs:

P0305 cylinder 5 misfire
P0307 cylinder 7 misfire
P0308 cylinder 8 misfire
P0300 Random multiple cylinder misfire

Exactly the same

Could you confirm that changing the spark plugs solved the problem ?

I mean, didn't it play again in the following days ?

Thank you very much


Best regards !!!

 

[CatmanV2]

Welcome

*Personally* I'd try swapping coils from 5 7 and 8 to another 3 cylinders that are not misfiring and see if the misfire moves. If not, repeat with plugs.

But that's me.

C

 

[sinver]

Welcome

*Personally* I'd try swapping coils from 5 7 and 8 to another 3 cylinders that are not misfiring and see if the misfire moves. If not, repeat with plugs.

But that's me.

C

Thanks for your quick response

The previous owner changed the 8 coils 3 years ago, it is confirmed that they have been changed, they are Bosch but they have already been replaced

I removed those three spark plugs and they had a lot of carbon, I cleaned them but although not so much, from time to time the error appears again

I ordered 8 spark plugs and I'm waiting for them to arrive, but confirming whether our colleague solved the problem is to avoid dirtying my new spark plugs if the problem persists.

Thanks !!!!

 

[CatmanV2]

Thanks for your quick response

The previous owner changed the 8 coils 3 years ago, it is confirmed that they have been changed, they are Bosch but they have already been replaced

I removed those three spark plugs and they had a lot of carbon, I cleaned them but although not so much, from time to time the error appears again

I ordered 8 spark plugs and I'm waiting for them to arrive, but confirming whether our colleague solved the problem is to avoid dirtying my new spark plugs if the problem persists.

Thanks !!!!

Well @Omar was on here on Thursday, so it's not impossible he'll reply The thing is because new plugs solved *his* misfire, doesn't mean it'll solve yours. Having said that, I'd be a bit surprised if you had coils failing after 3 years. Swapping plugs with cylinders that are not misfiring may show if the plugs are the issue, without 'risking' the new plugs, as it were

C

 

[allandwf]

The plugs may be sooting up, causing the misfire, so clears when they are cleaned. This me be a symptom of the problem but not the cause.

 

[sinver]

Well @Omar was on her one Thursday, so it's not impossible he'll reply The thing is because new plugs solved *his* misfire, doesn't mean it'll solve yours. Having said that, I'd be a bit surprised if you had coils failing after 3 years. Swapping plugs with cylinders that are not misfiring may show if the plugs are the issue, without 'risking' the new plugs, as it were

C

Do you mean swapping the spark plugs to see if the problem transfers to the other bank?

Or at least exchange the most accessible spark plug to test, right?

I think it's a good idea, I'll let you know...

Thanks again !!!

 

[sinver]

The plugs may be sooting up, causing the misfire, so clears when they are cleaned. This me be a symptom of the problem but not the cause.

I understand you perfectly, there may be something, a lamba probe perhaps that causes a rich mixture and fouls the spark plugs and then the error appears.

I thought about it but then why don't more DTCs appear related to the probes for example or to the catalysts?

we continue investigating...... thank you all, it is very pleasant for me to see the support you offer me

seriously thank you very much for your time

 

[CatmanV2]

Do you mean swapping the spark plugs to see if the problem transfers to the other bank?

Or at least exchange the most accessible spark plug to test, right?

I think it's a good idea, I'll let you know...

Thanks again !!!

Yes indeed. But to @allandwf 's point it may be a symptom, not a cause

C

 

[sinver]

Sí, de hecho. Pero hasta el punto de @allandwf puede ser un síntoma, no una causa.

C

ok ok I understand

Thks

 

[Omar]

Well @Omar was on here on Thursday, so it's not impossible he'll reply The thing is because new plugs solved *his* misfire, doesn't mean it'll solve yours. Having said that, I'd be a bit surprised if you had coils failing after 3 years. Swapping plugs with cylinders that are not misfiring may show if the plugs are the issue, without 'risking' the new plugs, as it were

C

Been away, yes no problems after new plugs, hope that doesn’t tempt fate!

 

[sinver]

He estado fuera, sí, no hubo problemas después de las bujías nuevas, ¡espero que eso no tiente al destino!

Hi all

Ok ok Omar Thanks you

Not have good news

This is my left catalytic, see picture

This is the problem

Thanks all for your comments

Great forum, excellents members !!!

 

[sinver]

Hola a todos

Ok ok Omar gracias

No tengo buenas noticias

Este es mi catalizador izquierdo, ver foto.

Este es el problema

Gracias a todos por sus comentarios.

Gran foro, excelentes miembros!!!

The right...

 

[CatmanV2]

Big difference Well done

C