Rough idle, occasional cold start smoke, 987 .2

[911hillclimber]

The other day when I parked it on a sloping driveway after a 15 minute run on country roads the car was still v warm when restarted, and the same oil cloud came out as it started as when it was cold 2 hours before.
the oil would be at a distinct angle rather hat flat on starting, is one or more cylinders would could be puddled in the oil with the engine off, such would be the driveway slope, about 15 degrees.
its booked into the busy Indie now for a week on Saturday.
the Indie has commented on this thread already, so almost knows the full story, got to help.

 

[911hillclimber]

After 2 days of standing still after the last short journey of 5 miles I left the car to tick-over for 20 seconds and switched off on my level driveway.

Went to Worcester today.
No smoke on cold start, nice run to Worcester, even hit 50 mph...speed cameras/limits galore.
Switched off in the level car park by the river after 10 secs tick over.
Re-start 3 hours later, no smoke.
I'm trying to find a rhythm to all this, ie, level parking, delayed switch off etc. smoke or no smoke.

The delayed switch off on my old 911 works a treat, but that is dry sump.

 

[SV_WDC]

Have you considered ambient temperature? From the point smoke is more noticeable in the cold
Understand the temp sensors do look at the ambient temperature on startup, if it's cold the mix can be quite rich and this may compound the issue

 

[911hillclimber]

Indeed!
today used the car, damp cool morning, no cold smoke start!
after a 25 min run let the car tick over for 20 seconds.
restarted after 2 hours, damp still and no smoke. Allow 20 secs to tick over, switch off.
just been out in it so 4 hours after the last switch off, no smoke.
after 1 hour, no smoke again and just ticked over for 20 seconds.

I hoping this 20 sec tick over period is helping!

 

[911hillclimber]

No it isn't.
Cold start this morning, smoke on start-up.
Jumped out of the car and the smoke is definitely FUEL, not oil.
You can really smell the excess.
Ran beautifully seconds after.

Thus, there is something sensing a temperature different to ambient and giving the engine a rich cold start?
That must be water or oil temp sender?
Anyone care to put a finger on it for me (us?)
Graham.

 

[SV_WDC]

Maybe ring OPC/Indy for a verdict?
Was told there is something that measures ambient temp, but couldn't tell you which component, or if it's the same across all Boxster/Cayman's.

 

[Motorhead]

Graham,

To avoid guessing which sensor may or not be problematic, just get some proper Porsche diagnostic kit on the case - PIWIS or Durametric. That should get it sorted once and for all.

Jeff

 

[911hillclimber]

I have a long thread on the PCGB Forum about the subject and was offered a free diagnostic check by Zuffenhaus in South Birmingham, an indie not known to me until today.
Arrived at a neat workshop with a wide variety of Porsche and classic WV's inside and looked around while I awaited my examination. The GP beach buggy was a pleasant surprise to see, the Camper van too plus a lovely 72T 911 # PCG XXXK, silver that looks like a familiar DDK car.
Met Sanjay there by chance!
The Boxster was plugged-in and the diagnostics run with the result of 'No Fault found' as the conclusion.
However, the technician decided to run a full parameter re-set, some 20 points on the engine and see how that worked out. Very interesting to hear the engine note change as the car was reset, esp the variable cam timing. A slight rattle I had suddenly disappeared.
The drive home was a delight, much smoother and clean revving 9it was good before) and now feels very refined, still 36 mpg at 70mph on the M42. :drunken:
I really have to say I was impressed by Zuffenhaus, the greeting we got, coffee and the detailed attention from the 32 year old Technician who actually knew about the car but also 'plugs-n-points and carbs'!
Tomorrow we go to Rolls Royce to Towcaster, it will be interesting to see/feel how the car is then, but today was a good day!

 

[911hillclimber]

Car runs really nicely.
No smoke this morning, 2 hours later leaving the RR Club estate, Smoke on start - up!
I give in.
I'll just accept it for what it is, or sell and buy something else with vertical cylinders.

 

[jmaddox]

I know this is a longish thread now and I have had some input already but are you sure it has the correct oil in it ? Not an equivalent but the Porsche recommended fill of Mobil 1 and also a proper OPC bought oil filter.
If it was mine I would change the oil and filter myself and fill it one bar below the maximum. You then will eliminate all possibility of the above and then drive it a while and monitor as you have been. If it behaves then top up the level a bit at a time monitoring as you go.

I can imagine how you feel about this and appreciate how much investigation you have done already.

 

[AndrewT]

Would it be worth talking to Hartech about the problem (https://www.hartech.org/)? They seem to be pretty well respected with regard to problems such as Intermediate Shaft Bearing failure (IMS), scored / scuffed cylinders, cracked cylinders / cracked liners, crank shaft bearing failure, snapped timing chains, etc...

 

[Motorhead]

Very frustrating for you Graham. I've heard good things about Zuffenhaus so you have to believe that, fundamentally, the car's OK. It's just a "smoker".

One final thought; although no error codes have been flagged-up it could be worth cleaning or even replacing the MAF sensor which I think may incorporate an intake air temperature sensor. A fault with the MAF could perhaps be leading to an extra rich mixture on start-up due to an incorrectly measured intake air temperature?

Jeff

 

[911hillclimber]

The Tech at Zuffenhaus checked the oil level and it is correct.
Fill that top bar and smoke is garrentee'd!
PCT did the last 40K Service so I would expect the oil and filter to be correct, but I don't actually know. will have a look at the bill!
Interesting thought about the MAF, will give that some thought.
I have read all the Hartech articles, very comprehensive indeed and an endoscope investigation might be next. not sure I want to know the result.
Wife seems to want to keep the car, she never drives it or will have the hood down. She thinks I should just get on with life!

 

[jmaddox]

Because it doesn't make smoke all the time I would be surprised if it was bore scoring. If it has a clear bore scope I would be inclined to keep it and try and accept that it does this. Difficult I know.

 

[SV_WDC]

Quite a videos on YouTube of it, some worse than others & may give some perspective to your issues.

 

[Motorhead]

Graham,

From your earlier comments (#45) I thought you'd decided that the smoke was fuel and not oil-related?

A borescope examination could open a can of worms - who knows? It's your choice but I tend to agree with John - and your wife..!

On the MAF issue, the engine will run in a default mode if you disconnect it. It may be worth trying just to see what happens but I'm not hopeful that it will get you any further forward. According to Design911 UK, a Bosch-branded MAF will set you back about £140, so it may be worth a punt.

Jeff

 

[911hillclimber]

Thank you all.
I have been in touch with the specialist I bought it from to get their opinion too. I was not looking to lay blame anywhere I should add.
It boils down to it was checked carefully pre-sale, they all do it so drive and enjoy!

I have used it hard the last few days, hard as in not driving it like my Skoda Diesel, use 5th a lot not get to 6th asap, but not fast as to get a ticking-off from the wife.
No smoke on cold or hot at all, typical!
I think it is so random I'll just get on with it.
I can keep changing parts and still not be sure it has fixed it.
We are going to SPA in Sept to the Classic meeting there, there is some paint to tidy up (stone chips) and then I'll decide to keep it or not.
If it goes then I certainly won't have another modern Porsche!

The 2009 BMW Z4 I had briefly before this car was far better built generally, killer engine and auto box with a huge list of nice options, but the ride was simply stupidly hard, 20" wheels and run-flats made for a ride that only discouraged you to use the car. no wonder it was low miles. The very long bonnet made it awkward to aim in car parks, luggage space was weak.
Should have simply bought some wheels as small as I could with normal balloon tyres and tolerate the rest!
This lot has cost me dearly but I know the wife likes the Boxster more than the BMW, so that is a bonus!

 

[Craig c]

I had a 987 gen 1, I was told at opc when I purchased the car about boxters doing this so wasn't too much of a shock when it did, was worse when it happened and people watching isn't what you expect, didn't really notice the rough idle though, I have a 981 now and sounds rough on idle

 

[911hillclimber]

Thanks Craig.
I have used the car over the last week on good runs, and once when I let my daughter try it.
Ididnt smoke on my occasion!
I took the car to Ludlow today, nice B and A roads and parked on a slope.
5 hours later, cold start, and no smoke!
recently I have been running the car in a gear lower than usual, I've higher revs for a given speed, but that is all, and I doubt that will have made any difference.
seems to want to behave itself!

 

[Craig c]

Hi,
I wouldn't worry to much about it, try enjoy the car, it usually happened to me when the car hadn't been run, I loved the 987 until I drove a 981 there is such a massive difference in the cars and refinement.