Hello everyone, first post!

I've recently acquired a 2004 continental GT W12.

Car was running fine then started to misfire and hunt at idle. Check engine light came on with code P0101 to do with mass air flow sensor or similar.

Checking the basics I found the negative battery terminal was completely finger loose. Charged the battery and checked the air boxes to find o/s filter had been blown which I assume was from the misfiring.

Fitted new air filters and took it for a drive. Drives OK but something feels off its not smooth and still feels like there is a miss.

Check engine light came back on with codes P0245, P0458, P0598, P2090 and P2088.

Any suggestions or ideas what to check before it goes to a specialist are appreciated.

Many thanks,
Lewis.

 

Did you reset all codes after loose battery terminal. Some of those codes can be associated with low voltage.
Try resetting and take car for a drive and see what codes come back. Its important to remove all the low voltage associated codes first.
You have made a note of all the codes so easy to see which are reoccurring. Depending on which type of diagnostics your using you should be able to see if its been logged as an intermittent fault a one off fault or a permanent fault.

 

Hi Frank,

Thanks for your reply. I'm using a generic OBD2 reader at the moment as I haven't got anything Bentley specific yet. I only had the p0101 code which cleared after tightening the terminal.

I then took it for a drive and it didn't feel right and I now have those 5 codes which won't clear.

Is it worth trying a battery off reset? If so how do I do this.

Many thanks

 

Ive never reset that way. I have a vas5054a so use that. However the principle apparently works . Disconnect the battery the way the hand book says and leave for 20 minutes then reconnect the correct way. However expect a plethora of codes that will require resetting. You will have to get the widows to relearn their position which is easy. You might get a suspension or traction control fault alarm, just ignore them and drive the car a few meters and they reset themselves. The rear 1/4 windows can be a bit slow to relearn their position in life but they eventually do.

 

Hi Frank,

I'm resetting using the obd11 code reader.

I was just thinking a battery off reset may help like it sometimes does on my JLR vehicles.

At the moment when I drive the Bentley there is definitely something amiss with the engine it's not smooth as it should be does feel like a light misfire.

I dont personally feel the codes I have give me any direction what to check so I concur with your thinking that they could be low voltage related but this makes me wonder whats going on with the W12.

Kind regards

 

I quickly googled the codes you had and one is for a deteriorating cat and another for a cam sensor.
When the ecu drops in to limp home mode you will know because it will be less powerful and less responsive. Your not getting any misfire codes by the look of it. So my advice for what its worth is to reset all the fault codes with the ignition on but not running . Hopefully you will have no fault codes. Start the engine end see how many codes appear. You don't want to be doing any more power runs until you have no more codes.
What concerns me is your description of the air filter box. What exactly do you mean. I would hope its not been damaged by blow back from the engine.
Im also concerned that you ate not doing your cats any good and perhaps they have already been compromised.
Get another fault code read out and post them here. There are greater minds than mine who will be able to crunch the data better and give you more insight.
There is nothing wrong with disconnecting both batteries and waiting a while. Its worth a try.

 

Hi again Frank,

This is what I meant by the air filter box.

This was the state I found the filter in. The actual airbox itself is completely fine. I have fitted new filters.

Not driving the car at all now and will have it recovered to a specialist in Crewe who's employees are Bentley trained.



disconnected both batteries and waited 20 mins before reconnecting.

Rescanned codes before startup and no codes found. Started engine and the same 5 codes mentioned above immediately came back.

I have discovered that the drivers side o/s (RHD) sounds like there is an exhaust leak. I can smell exhaust fumes strongly on this side and things look very sooty down there please see photo below.

 

 

I've attached a picture above to show you the state I found the drivers side air filter in. The filter box itself is absolutely fine.

Disconnected the batteries, waited 20 mins and reconnected then scanned for codes engine off. No codes. Started engine and the same 5 codes above came back immediately.

I've discovered that the engine sounds louder on the drivers side o/s (RHD car) and there is a strong smell of exhaust fumes. It also looks very sooty down in there please see photo above.

 

I dont like the look of that. Hopefully some one on here here might have had something like this. But that needs further investigation. A ramp and a camera to see what's going on. I suspect cat damage hole or burnt out ir perhaps a manifold or turbo/manafold failure. However I would just be guessing.
I would suggest stop driving it as you dont know what further damage may be done until you have a better idea of what's going on. How much of that air filter do you recon has been sucked into the engine?

 

I'm getting the car recovered to GT services in Crewe next week.

Not been driving it since the check engine light came on with the 5 codes.

I dont think any filter got sucked into the engine as luckily the pipe out of the airbox down to the turbo has a plastic mesh on it. This is where I found the debris.

 

It will be interesting to hear from you with the outcome.
Hope its a minor issue that just looks bad but isnt.
Good Luck👍
Frank.

 

Thanks for your help Frank, I'll let you know when the specialist has taken a look.

I understand these cars can generate large repair bills but it would be such a shame to get a big bill not even 1 week into ownership!

Ive not even managed 100 miles in her yet.

 

There is a horrible thought going through my mind saying you were probably sold the car with a known issue .
Was it a private sale or via a dealer. Surly you must have some redress to a warranty?
As you say you have only just bought it.

 

It was a private sale from a chap that had owned since 2011.

He had replaced it with a new Rolls Royce not that that goes any way to suggest the car didn't have an existing fault he was aware of.

hmm