Cadillac CTS Help

[ellarry]

Hi Everyone,

Brand new member of the forum, I wonder if anyone can provide any help or advice, re: Cadillac CTS 3.6 Sport Luxury 2006 UK RHD.

Devon, UK based and I have a RHD CTS 3.6 2006 (Manufactured in 2005 I believe).
I have P0451 & P0453 codes.

The definitions for the codes I think, but not certain are..
P0453 - Evaporative Emissions Control System Pressure Sensor High Input
P0451 - Evaporative Control System Pressure Sensor Range/Performance

There are no issues with performance or the car running.
The only indicator of an issue is the yellow engine light on the dash.
However this light will probably result in a failed MOT which is due in July.

Perhaps someone can suggest a fix or work around, as finding it very hard to locate a mechanic/garage locally (Devon, South West UK), that is confident to work on it. I can't afford to make any expensive mistakes.
It seemed that the p0453 code had been fixed by using a brand new petrol cap I recently purchased/received from the US, but that code is now back on after a few days.

Thanks in advance for any help or suggestions.

[irocfan]

as strange as it may sound it my be worth a little look on the camaro forums as they share engines (IIRC).

[Chicken chilli madras]

Fuel tank pressure sensor maybe.

[LuS1fer]

Have you changed the fuel filter?
Gas cap?

https://www.youtube.com/watch?v=foFeQ7Geh24

[ellarry]

Hi,

Sorry to all that posted a response for the delay in replying, for several days I have been unable to post a reply due to the forum being locked for new posters (message I received when trying to enter a reply).

From more searching on the internet about this, it seems it may be many things, a couple being.. a faulty fuel sensor or a vent stuck open somewhere on the fuel system. Still trying to find a mechanic/garage in the Plymouth area confident enough to diagnose and fix. Cannot find anyone, perhaps someone here has knowledge of a somebody great with US cars nearby.

Already tried replacing the fuel cap, and this coupled with filling the tank up full, results in the light staying off until some of the fuel is used, or a couple of switch offs/start ups.

Replacing the fuel sensor is fiddley I beleive, as it may require removal of drive shaft etc. To access the sensor loacted somewhere on the tank. So trying to ensure this would definitely fix the issue. Hopefully I can find someone to make a firm diagnosis via here.

Thanks again to all who have replied.

Cheers

[Tony427]

I've had one of these cars and there's a solonoid controlling the vent from the tank into the inlet manifold located on the top of the engine on the drivers side under the plastic engine cover. It can sometimes be heard ticking/ clicking away. I would have a look at that in the first instance.

Cheers,

Tony

[ellarry]

Thanks for the suggestion Tony,

I will mention it to whoever I find to work on the car, (not found anyone yet, who is confident to do so).

Also something just happened yesterday...
The passenger door won't open from inside or outside, it unlocks (lock button pops up and down) but it wont' open. Unfortunately the car only has outside key access on the drivers side, no keyhole on passenger door, so can't open it like that.
Real pain in the ***** as very much need the passenger seat for someone who has mobility issues.
Now to find a garage/mechanic in Plymouth to open the door and then fix it asap.

[The test driver]

Chicken chilli madras said:

Fuel tank pressure sensor maybe.

This^

I look after a mates one for him and it had the exact same problem, need to drop the tank to get at it.

If you ever have to change the timing chains on it then I've got the timing tools as a side note.

[ellarry]

Hi The Test Driver,

Thanks for your reply. Where are you located?

[The test driver]

ellarry said:

Hi The Test Driver,

Thanks for your reply. Where are you located?

Silverstone not far from racetrack.

[Cantaloupe]

I had one of those, lovely car, the only issue I had was a diff or prop shaft vibration.

Are you using the same petrol station to fill up ?

Sometimes poor petrol quality, [ or water in the tank ] can set off the EM light.

[ellarry]

Funnily enough Cantoloupe, about 8 weeks ago used Asda petrol for the first time, (low on fuel only option).
Then parked the car less than half a mile away and left it for a couple of hours. When starting up on return, the car cut out instantly (never ever happened before), started it again adn drove away. Car was running wrongly, jerking, stuttering etc. Called roadside recovery and also the Asda filling station (who said the fuel was correct and they had no other complaints as first my thought was that the filling station maybe had the wrong fuel in the wrong pump. The roadside recovery guy ran tests and then ran the car for about an hour to waste the fuel (with some water droplets coming out of the exhaust pipes), afterwhich filled up with Esso (regular fill up) and never had the issue again. So looks like the Asda fuel must have had water in it. The engine lights pre-dated this, so it was not related.

Last week/ten days had a new fuel sensor fitted and the lights are now out, so seems that was the issue. However since having it fitted, the fuel consumption has nosedived, by about 3/4 x . Before using about £20 per week of fuel, now £80+ for the same weekly journeys. If this continues, might replace the new sensor with the old one after the MOT in July.

[LuS1fer]

Every gallon of burnt petrol produces a substantial amount of water but as it is steam, you don't see it.