991.1 GTS Engine replacement and suspension arms

[Chris93]

Hi All, Hope you are well.

Was seeking some advice, I bought a 991.1 GTS from OPC Teesside in April. It had a number of issues and noises mainly from the front suspension which OPC Reading diagnosed to be the front suspension arms which have had the part codes now changed so all need replacing as a set along with a number of interior rattles. Teesside decided to take the car back up last month to diagnose themselves and I asked them to listen out for a rough sounding noise for about 10 seconds when starting the car which then goes away.

They called last week to say there is a technical bulletin out for this and they did a borescope where they found cylinder scoring and had to send off to Germany but the car will need a new engine Germany now have to choose whether to replace the short block or full engine. I can't see any examples of this happening on these 3.8 DFI engines and the replacement engine is going to cost in excess of £35k under the warranty, does this still happen to these cars?

I haven't had a car for a month now so and doesn't look like it will be back anytime soon so would be great to hear of anyone else's experiences. Also does anyone else know about these noisy front suspension arms that now have a superseded part number?

Thanks
Chris

 

[Dylan1]

that’s very bad luck
condolences

 

[Chris93]

No one has had any experience of either of these?

 

[boardingnath997]

I’ve seen very few instances of this happening with 991 series. More likely to hear of PDK issues. Incredibly bad luck but you must be thankful you have a warranty. What was the sound you were hearing?

 

[Dave jones]

So sorry to hear this. Not heard of any one having engine problems with a 991 .

 

[Peter_Bull]

I would reject the car immediately. Its not fit for purpose.

This link may assist you: https://www.citizensadvice.org.uk/about-us/our-work/citizens-advice-consumer-work/the-consumer-rights-act-2015/

 

[Chris93]

Thanks for your help guys, So I have an update here. The car has been in for 2 months and after stripping down Porsche have identified 2 scored cylinder bores and the crankshaft bearings are the cause.

Apparently there was a faulty batch of ignition coils in a very specific window which my car is part of that caused the spark to fire incorrectly and eventually offset the pistons and put load on the crankshaft. Porsche are completing a short block replacement on the car as well as new coils and rebuilding the engine, I would have preferred a total new unit but it sounds like Porsche approved warranty will do the cheapest possible solution so I think this is still a good result.

Its been frustrating how slow Porsche Germany are to respond and approve work to the dealership, seems like a broken process to me. They also haven't been able to investigate the suspension as the car has had no engine in...

If your 991.1 makes a rattle for 10 seconds at startup and is 2015 ish then worth having this checked, apparently they know of 2 other UK cars this has happened to only though so don't be too concerned

Thanks

 

[911Time]

Hi Chris, very sorry to hear of your engine woes.

As the nature of the suspected fault would have caused cumulative damage, it would be very interesting to know, at what mileage the noise started to become apparent.

Still can't quite wrap my head around how a faulty coil/coils could cause firing before TDC and lead to engine damage.


Would have thought cold pickup, or cylinder ovality differences would be more likely causes of scoring in a DFI engine but every day is a school day

Nevertheless, glad to hear that Porsche are doing the right thing.

 

[Chris93]

Thanks Mark, yes its all a bit of a mystery to me too as I couldn't picture it myself but somehow 2x Cylinder bores were scored in an engine where this is apparently not a known issue and the Porsche technical bulletin indicates it isn't GTS or Powerkit related but down to a set of bad coils affecting a small batch of cars, interesting they wouldn't just do a recall?

I picked the car up at 32k miles and it was making a rattling sound from the rear which I had assumed was normal or exhaust related, I never noticed any issues to drive other than several people commenting the engine made a fair bit of smoke under hard acceleration.

Porsche Germany have been really quite poor, slow responses and doing whatever they can to find the cheapest solution possible whilst Teesside have been trying to demonstrate there is an issue affecting multiple parts. They have estimated 35 hours labour all in due to all the Procedures Germany have made them undergo.

 

[911Time]

Hi Chris,
Thanks for the additional information!

I'm sorry to say that from what I hear, bore scoring can still be a problem on the 9A1 (997.2/991.1) engines, albeit one that is currently far less well documented and seems to occur, for reasons very different to those of the previous engine.

The noise and smoke you describe are a dead giveaway but 32,000 miles isn't very much and that's worrying!

I hate to be critical of 'the mothership', so I'd like to think the slow response reflected time spent on further investigation but I'm still dubious about the explanation regarding the coil packs and the apparent penny-pinching by the factory, seems to miss an opportunity to impress with a truly comprehensive & generous solution.

 

[Motorhead]

Chris,

Like yourself and others I can’t fathom the explanation you’ve been given about the cause of your engine’s bore scoring, but since Porsche are familiar with the problem we must assume that it’s been thoroughly investigated by the engine development team and they’ve reached the conclusion that it was due to faulty coil packs.

I don’t know why it’s taken so long for Porsche to decide upon a course of action to effect a repair but you have to remember that you’re covered by the Extended warranty rather than the Factory warranty and as such is provided by a third party insurer and therefore you are subject to their scrutiny and approval rather than exclusively that of Porsche. This could have led to lengthy negotiations between the two parties.

The work itself will be guaranteed for I believe 2-years, but maybe you can negotiate say a year’s Extended warranty FOC in the circumstances?

Good luck!

Jeff

 

[Chris93]

Update here all -

Car is back from having a new short block and many associated parts after 3 months. Feels much better, engine feels stronger and car feels noticeably quicker, Haven't been able to fully extend it yet but can't see any smoke coming from the back now either.

 

[911Time]

Hi Chris,

Glad to hear you finally have your car back! How long do you have to run her in for?

Regarding the suspension: My 991 4S is now at C30,000 and has developed an intermittent knock, from the lower front suspension arms, when going over undulations in the road. Is that the same as your issue?

 

[Chris93]

Thank you Mark, I was told officially that I wasn't however I am going easy for the first 1000 miles. I have taken it to 7000 ish once or twice and it feels great, pulls very hard at the top end now.

And yes this sounds identical to my issue but no one has been able to find any movement in the arms now which is frustrating, apparently they can be noisy without being worn and moving so unless I replace all 4 as you can't just do 2, I need to live with it sadly. I wonder if the front arms are any different on a C4 to a C2 out of curiosity

Chris

 

[911Time]

Hi Chris,

FWIW, I'd be doing exactly the same, running her in and varying the rev range, in a gradually ascending fashion.

Coil pack issue not withstanding, the more I learn about the 9A1 DFI engine, the more important it seems for longevity, to warm them up thoroughly (until the oil is hot) before going full bore.

AFAIK, the lower control arms are the same in the following manner:
C2 & C4 standard (non PASM) suspension
C2S & C4S with PASM
SPASM equipped cars

You mentioned in your original post that there had been a change in the part for the lower control arm. Were you given the impression, that this was solely to address the knocking noise?
Why would you need to replace both front and rear lower control arms?

I've found mine gives an audible knock when riding over dips in the road - as if the suspension is 'unloading' in the dip, before the next compression. This doesn't occur all the time but tends to happen after the car's been sat for a while and to be honest, I assumed the bush had just become 'set'. I lubed the area with some WD40 back in the Summer and the noise disappeared for a while but returned in the Autumn.

I'd be most grateful for any more info, such as whether there's a TSB, just incase I can claim updated arms through the warranty.

Many thanks!