Here's a New One: SES Light for P0011 Turned Itself Off

[peter540]

Maybe 8k miles and a couple of years ago, my '03 540/6's TCGs were done. All's been fine up until several months ago, when the dreaded SES turned on -- it was P0011. No other symptoms, and the engine sounds great. I suspect that either the timing chain tensioner should be replaced, or the trigger wheel should be tweaked on the bank one side.

The SES light has been on for several days, and today, something happened for the first time in my 17 years of ownership of this car: the SES light turned itself off when I started the car. Weird. I checked with my code reader, and the P0011 is still there -- and the SES light is functional (i.e. the light bulb's not burned out).

Anyone ever have THEIR SES light for a P0011 or P0021 TURN ITSELF OFF?

Thanks, as always!

--Peter

[TiesTorN]

I've never seen p0011 or p0021 illuminate that light. it was probably something else like out of range fuel trim.

[JimLev]

Was the tensioner replaced when the guides were replaced?
Was P0011 in shadow memory? If it was that won’t make the CEL come on, it’s just stores what faults are or were present.
Some faults need to happen 3 times before the CEL is turned on.
I’ve helped a few guys that got P0011 after they replaced their guides, usually it pops up from the timing not being done properly or the trigger wheel position not set correctly.

[peter540]

Was the tensioner replaced when the guides were replaced?
Was P0011 in shadow memory? If it was that won’t make the CEL come on, it’s just stores what faults are or were present.
Some faults need to happen 3 times before the CEL is turned on.
I’ve helped a few guys that got P0011 after they replaced their guides, usually it pops up from the timing not being done properly or the trigger wheel position not set correctly.

So the SES has popped up before in the past couple of months. I've cleared it, and then it returns. This time, when the SES turned on, I didn't reset it. Then yesterday, the light didn't come on, but the code was still present.

So yeah, I was thinking of two possible causes/fixes: timing chain tensioner (i.e. replace with a new one to see if that fixes things) or tweak the trigger wheel.

--P

[peter540]

One other question: might a faulty camshaft position sensor cause this sort of problem? I'm expecting not.

[JimLev]

It’s possible I guess, but cam sensors have their own codes.
Clear your P0011 and see if it returns.

[peter540]

It’s possible I guess, but cam sensors have their own codes.
Clear your P0011 and see if it returns.

Yeah, I've cleared the codes several times, and they've returned. This last time, the SES popped up with the code, then the SES light suddenly was off. That suggests to me that the timing issue is intermittent. So timing chain tensioner replacement and trigger-wheel-tweaking are the two things I can think of to try and fix the problem.