987.2 Boxster S Cam/Crank issue

987.2 Boxster S Cam/Crank issue

Author
Discussion

Chris-596aj

Original Poster:

17 posts

76 months

Saturday 30th July 2022
quotequote all
Help!

Bought the above (2011 Boxster S 987.2) privately 2 months ago, Drive home was fine, later that evening car went into limp mode displaying fault "crankshaft/camshaft limit value exceeded" and "camshaft sensor 1 limit exceeded". - cam to crank correlation error.

Initially there was suggestion of a stretched chain but as this comes as part of the short block Porsche said this was extremely unlikely as 3 main dealers had never replaced this on the DFI engines.

Upon inspection the sensors were non-genuine so the decision was made to replace the sensors but as i wanted to replace the clutch anyway the engine was removed with the following work completed with all Porsche parts (might sound overkill but the car was going to be a keeper)

Replaced cam and crank sensors
Checked wiring to sensors
Replaced cam chain tensioners
Replaced weeping cam cover gaskets
Cleaned out all port holes
Full service (spark plugs etc)
Replaced clutch, flywheel
As well as a few remedial bits while the engine was out.

Engine then refitted and road-tested for 3/4 days all okay. Faults gone and running perfectly.

3 miles after i picked her up and got home she wouldn't start. Ignition would turn but nothing happened - seemed electrical. Recovered back and recoded - now working.

3 miles after i picked her up again went to refuel and wouldn't start again. This time it would crank but just stuttered and wouldn't start. Recovered again and ALL the previous fault codes above have re-appeared.

All the work has been completed at a respectable independent and followed the advise of Porsche main dealers too.

I'm stuck and broke.

Anyone have any similar faults or ideas at all?

Any help very much appreciated!

KPB1973

929 posts

106 months

Monday 1st August 2022
quotequote all
Blimey. Never heard of anything like that, but I hope you get it sorted without too much additional pain and expense (from a fellow 987.2 BS owner).

Chris-596aj

Original Poster:

17 posts

76 months

Monday 1st August 2022
quotequote all
Thanks - its an absolute nightmare.

So many different suggestions of what i can be but still no further forward...


Condi

17,978 posts

178 months

Monday 1st August 2022
quotequote all
Sounds like a random loose connection or corrosion in the wiring. But where, and how you find it, is a different matter.

Bright Halo

3,251 posts

242 months

Monday 1st August 2022
quotequote all
Where in the country are you, can you get it to a well respected indy specialist assuming you do not use one already?
Thinking the likes of Cotswold Porsche?

stevemcs

8,993 posts

100 months

Monday 1st August 2022
quotequote all
Was the timing checked when the engine was out ?

esotericar

745 posts

34 months

Monday 1st August 2022
quotequote all
If it's definitely true that the car has at times run faultlessly after being "road-tested for 3/4 days" that implies it's not a major mechanical fault. If it was a mechanical fault like a stretched chain, you would not expect it to run faultlessly for several days before the fault code returned.

Instead, that implies something more along the lines of an electrical, sensor or wiring issue. But, of course, seemingly impossible things do happen. I'm slightly sceptical just how much the car was road tested and that the reality may be nearer to car was taken out for a quick zap and seemed fine, but that's another story. Anyway, I doubt anyone on here is going to come up with an answer.

Problem you've got is that it's hard to know what steps to take next while the fault is unclear. You could fit a breaker sourced replacement engine and still have the fault if it's something in the loom or ECUs.

If your indy can't fix it, you either have to try another indy or dispose of the car. Having dealt with a lot of UK indy's, if I had a difficult car like this, I'd be booking it in with Precision Porsche in Uckfield and getting the guy works there and goes under the username Demort on 911uk.com to work on it.

The guys at Cotswold mentioned above are good too, as are a number of other outfits one could mention. But for this kind of fault finding, the above is where I would go.

Chris-596aj

Original Poster:

17 posts

76 months

Monday 1st August 2022
quotequote all
Thanks guys all very helpful.

I know the car was extensively road-tested because it completed 100 miles at my request.

The timing was checked and all fine. I agree it just cant be mechanical when half the time its fine. The faults tend to happen when the car is warm.


The faults showing are Camshaft Sensor 1 + 2 Exceeds limit value and Intake Camshaft Position Timing, Bank 2 implausible.

I'm still debating what to do next....

Chris-596aj

Original Poster:

17 posts

76 months

Monday 1st August 2022
quotequote all
Forgot to mention I'm not far from Cotswold Porsche so that could well be an option.

andygo

6,955 posts

262 months

Monday 1st August 2022
quotequote all
I put this into Google:

The faults showing are Camshaft Sensor 1 + 2 Exceeds limit value and Intake Camshaft Position Timing, Bank 2 implausible.

The search string came up with several threads on other forums and whilst not providing a straightforward fix, they might lead you on a road to help identify the actual issue. Although some threads are VW/Audi faults, I'd imagine the diagnoses & sensors would be similar .Is there a fault number code, eg P12345 which might help direct your search even more.

Good luck.

elisered

243 posts

89 months

Monday 1st August 2022
quotequote all
Post your issue on boxa.net - an awful lot of first hand technical knowhow available to you there.

Porschekiduk

42 posts

211 months

Wednesday 3rd August 2022
quotequote all

Hi, they should be able to read camshaft deviations with the diagnostics they have, you then look at if live readings are also fluctuating, or is the dme misreading the info. I wouldn't have thought it would be mechanical, as you would expect it to be more frequent

There may be an opportunity to scope both sensors.

The post states timing chains not sold separately, but they are shown at £148 each.

Do you work with Paul, in Bristol, if yes i have your codes, and will put into the Porsche online fault finding section, this may give more information.

Chris

ATM

18,957 posts

226 months

Friday 5th August 2022
quotequote all
Chris-596aj said:
Upon inspection the sensors were non-genuine so the decision was made to replace the sensors

Replaced cam and crank sensors
Checked wiring to sensors
The non-genuine sensors peaked my interest

This is not the sort of part someone would just replace I'd guess unless they were already chasing a problem

So perhaps this problem has been ongoing with the PO before they sold it to You and if this is correct maybe they gave up before the problem was properly diagnosed and then fixed

All guess work obviously

Chris-596aj

Original Poster:

17 posts

76 months

Saturday 6th August 2022
quotequote all
Thanks for all the comments guys.

Chris, yes this is me - thanks so much for your help so far via Paul.

Not sure if Paul spoke to you Friday or not but i would really like yourself or someone you trust to take a look directly? My numbers is 07817661132 if easier.

Many thanks