Porsche Cayenne e-Hybrid - Porsche Hybrid

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Sat 6 Feb 2021 20:32
Porsche Cayenne e-Hybrid - Porsche Hybrid - John Derbyshire

Last year in March, just a little over 10 months ago, after owning a series of four Range Rover Sports, I bought myself a Porsche Cayenne Hybrid. I went for the hybrid technology because I thought it would deliver a lower cost per mile and also in a diesel declining motoring world I thought it would have a better residual value.

The car defaults into e-mode when switched on, and if you put the destination into the sat nav, it uses its electric power very intelligently, saving the 27 miles worth of electric power for when it is most cost effective. Most of my journeys are about 8 miles, making the average return trip well within the electric capability of this car. When I can charge the batteries free from an array of solar panels, it did indeed seem like a win / win situation.

BUT: After ten months and only 2600 miles (you can’t go far in a lockdown), the car told me that “e-power was not available”. When I telephoned my local Porsche service they said that they had never experienced this before, and because no error message was being displayed, they thought I was doing something wrong. They agreed to have a look at the car and later that day told me that the oil level was too high because fuel had entered the oil because of the way I had been driving the car on short journeys, not using the engine enough and not therefore not getting the oil up to a temperature high enough to eliminate the fuel from the oil.

Sounded a little unbelievable to me, and to the salesman that I dealt with. Porsche customer care had absolutely no idea at all. But it turns out to be true! In fact more unbelievable and annoying was that Porsche customer services (incidentally the worst customer service experience I have ever encountered) had never heard of the dealership, and even asked me if my car at 10 months old was under warranty.

The only remedy was to replace the oil and filters at a cost to me of £400.00. Having paid over £80,000 for a prestige make of car, I did not expect to have to pay £400.00 for a fault that developed during the warranty period, neither did I expect to have to change the oil and filters every 2500 miles or not to be able to drive a hybrid vehicle in its default electric mode.

This raises a few concerns.

  • Am I being told the truth?
    • It does sound unbelievable that fuel has entered the engine oil especially when the engine is not running most of the time.
  • There is nothing in the instruction manual about overriding the default e-mode, or any advice about driving in the different modes.
    • I have now been advised to run the car on its petrol engine until the oil has reached temperature before engaging e-power.
  • Is this a common fault?
    • I have spoken to two large dealerships, who have made enquiries within their large groups, and not yet spoken to anyone who has come across this before.
  • Is plug-in hybrid technology going to be a success?
    • Obviously the car is designed, by definition, to be driven in the default mode of e-power. It will do this for 27 miles, and if the sat nav is not engaged it will remain in e-power for the duration of most journeys. Porsche tell me that “Insufficient engine use" is what has caused the fault.
    • Are all PHEV technologies the same, or is this problem unique to Porsche? Or unique to my car?

The total lack of support from Porsche has been staggering, their attitude sickening and the car very disappointing. I wish I had stuck with another Range Rover.

I sincerely hope someone in the motoring world can shed some light on my situation.

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Sat 6 Feb 2021 20:56
Porsche Cayenne e-Hybrid - Porsche Hybrid - mcb100
Has anyone else on any Porsche forums reported similar?
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Sat 6 Feb 2021 21:02
Porsche Cayenne e-Hybrid - Porsche Hybrid - sammy1

Am I glad I don't own your car as I would drive it in exactly the same way! If you can drive on battery surely this is what you should be doing and then let the petrol engine take over. It does sound that you have been using the petrol engine and not going sufficient miles to warm it up. Why excess petrol is in the sump with the oil is does not make sense. Porsche are probably treating you as their guinea pig, but for the savings made for 27miles on battery not worth deploying it. I think you ought to escalate this with Porsche as I feel that you are bound to have done some longer journeys on petrol?

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Sat 6 Feb 2021 21:22
Porsche Cayenne e-Hybrid - Porsche Hybrid - craig-pd130

They agreed to have a look at the car and later that day told me that the oil level was too high because fuel had entered the oil because of the way I had been driving the car on short journeys, not using the engine enough and not therefore not getting the oil up to a temperature high enough to eliminate the fuel from the oil.

Two words: bull ordure. Oil dilution can and does happen with modern DIESEL-engined cars, but not with modern petrol-engined cars that have multipoint fuel injection, catalytic converters etc.

If excess petrol was being introduced in such quantities to raise the oil level significantly, the engine would be running so rich that it would poison the catalytic converters and the O2 sensors in the exhausts, which would trigger 'check engine' and emissions lights as a minimum.

You may have had some condensation build-up in the oil, but not fuel. The dealer doesn't know what it s doing.

I ran a BMW 225xe plug-in hybrid for 3 years. No problems ever with the petrol engine, despite often going several weeks without the petrol engine ever kicking in. What did happen sometimes in below-zero ambient temps was that the car would not allow pure electric-only running because the battery pack was not warm enough. However, if I plugged in the car and set it to pre-condition, it would happily engage pure electric mode.


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Sun 7 Feb 2021 10:57
Porsche Cayenne e-Hybrid - Porsche Hybrid - daveyjp

If there is a requirement to use the petrol engine occasionally and extended periods of EV use only is not advised this should be printed in big letters somewhere in the handbook.

However the oil dilution is complete and utter BS.

Porsche appear to be in the stable of 'our cars are expensive, so they must be good. Once we have your money we don't care'.

A neighbour of my sister has a 1st generation Panamera Hybrid 3-4 years old. Just before Christmas she was doing the usual pre Chrsitmas stuff. Went shopping, returned to the car, pressed start button, into gear and the car gave maximum power resulting in the car going through the car park wall across a road and through a garden wall of a house opposite.

This is not a new car to her, show knows how to drive it as she has done tens of thousands of miles in it. It is now at solicitor stage as Porsche refuse to acknowledge there was a problem.

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Sun 7 Feb 2021 12:54
Porsche Cayenne e-Hybrid - Porsche Hybrid - skidpan

If there is a requirement to use the petrol engine occasionally and extended periods of EV use only is not advised this should be printed in big letters somewhere in the handbook

I seem to remember when a couple of engineers at work had Mitsubishi PHEV's as their new company cars it was stated in the handbook not to panic if the petrol engine started despite a full battery when the car had been used solely on battery power for a certain period. This was to ensure that the petrol engine was used periodically to circulate oil etc.

Never affected either, the cars were never charged. Only had them for the minute company car tax dodge.

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Sun 7 Feb 2021 15:22
Porsche Cayenne e-Hybrid - Porsche Hybrid - craig-pd130

I seem to remember when a couple of engineers at work had Mitsubishi PHEV's as their new company cars it was stated in the handbook not to panic if the petrol engine started despite a full battery when the car had been used solely on battery power for a certain period. This was to ensure that the petrol engine was used periodically to circulate oil etc.

My 225 used to do that too after several consecutive days of pure EV driving. Once every few weeks I'd get in and the petrol engine would fire up immediately on pressing 'Start.' It would run for a couple of minutes then cut out if it wasn't needed. Presumably some sort of mileage or time counter was built into the ECU.

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Sun 7 Feb 2021 14:04
Porsche Cayenne e-Hybrid - Porsche Hybrid - edlithgow

They agreed to have a look at the car and later that day told me that the oil level was too high because fuel had entered the oil because of the way I had been driving the car on short journeys, not using the engine enough and not therefore not getting the oil up to a temperature high enough to eliminate the fuel from the oil.

Two words: bull ordure. Oil dilution can and does happen with modern DIESEL-engined cars, but not with modern petrol-engined cars that have multipoint fuel injection, catalytic converters etc.

One word : Untrue.

Oil dilution is a well publicised problem with , for example, petrol Honda CRV's and Civics (non hybrid). . It seems quite plausible that extensive electric operation of a hybrid would aggravate such a problem, if it shifted the IC engine operation toward short-tripping

Another word: Implausible.

Admittedly, one might expect fuel dilution with diesel to be harder to reverse by getting the sump hot, because diesel is less volatile, but if the sump never gets hot that's a moot point.

OTOH, a given level of fuel dilution with petrol is potentially more damaging, because the fuel has a lower viscosity, This is likely to be especially true in combination with modern low viscosity oils.

Another word? Maybe irrelevant? As in, how is a catalytic converter going to address dilution of the oil by excess petrol?

Edited by edlithgow on 07/02/2021 at 14:14

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Sun 7 Feb 2021 15:31
Porsche Cayenne e-Hybrid - Porsche Hybrid - craig-pd130

Another word? Maybe irrelevant? As in, how is a catalytic converter going to address dilution of the oil by excess petrol?

If oil dilution is happening with some petrol cars, then the fuel injection curves on those cars must be very badly mapped.

And when I mentioned cats, I'm pointing out that if an engine is overfuelling to the extent that it's diluting the oil, the mixture will be excessively rich (the equivalent of leaving the choke on in a car with carbs), which would quickly poison the cats and would certainly throw a CEL or emissions warning light.

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Sun 7 Feb 2021 19:59
Porsche Cayenne e-Hybrid - Porsche Hybrid - sammy1

Honda's direct injection 1.5 has a manufacturers acknowledged problem. It seems that petrol is injected at very high pressure into the combustion process and when cold the petrol can run down the cylinders into the sump thus diluting the oil. It seems their cars have a warning lamp should the sump overfill. Apparently the cooling system on the car is over efficient and the engine might not get up to a temperature where the fuel in the sump will be vaporised and recycled through the combustion process.

So it would seem that design is the problem and as usual not the customer which Honda apparently hold their hand up USA!!

I do not know how a modern Porsche engine works but to dump fuel into the sump and tell the customer it is their fault because they do not how to drive the car sounds bizarre.

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Sun 7 Feb 2021 21:58
Porsche Cayenne e-Hybrid - Porsche Hybrid - Brit_in_Germany

How are the particulate filters on petrol engines cleaned if not via a fuel injection routine?

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Sun 7 Feb 2021 22:18
Porsche Cayenne e-Hybrid - Porsche Hybrid - RT

How are the particulate filters on petrol engines cleaned if not via a fuel injection routine?

AFAIK the PF on petrol cars doesn't need regeneration as the exhaust temperatures are much higher than diesels.

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Mon 8 Feb 2021 00:34
Porsche Cayenne e-Hybrid - Porsche Hybrid - edlithgow

Another word? Maybe irrelevant? As in, how is a catalytic converter going to address dilution of the oil by excess petrol?

If oil dilution is happening with some petrol cars, then the fuel injection curves on those cars must be very badly mapped.

And when I mentioned cats, I'm pointing out that if an engine is overfuelling to the extent that it's diluting the oil, the mixture will be excessively rich (the equivalent of leaving the choke on in a car with carbs), which would quickly poison the cats and would certainly throw a CEL or emissions warning light.

Well, that appears to be an unsupported hypothesis. Its good practice to leave words like "certainly" out when making them.

I doubt its always true. The mixture doesn't have to be massively over-rich for long periods for petrol to accumulate in the sump. There just has to be excess fuel at start-up (which is normal) and short-tripping.

Its probably relevant that the Honda engines affected were turbo-boosted, which increases blowby. I havn't heard that the catalysts were generally affected as you describe, and I think its unlikely, because that would have made it harder for Honda to deny fault, which they did.

I'd add another word "unhelpful" (that's four now, not counting your two) to the list. Honda "held up their hand" on this because they lost a class action in the US courts, so the hand was in cuffs.

If a similar thing happened to the OP's car, that's a (probably inherent) design fault, and. the Honda precedent supports him in any negotiations with his dealer and parent company.

Denying its possibility is therefore not helpful

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Sun 7 Feb 2021 23:58
Porsche Cayenne e-Hybrid - Porsche Hybrid - Avant

Welcome to the forum John, and thanks for telling us your story. You'd think that a manufacturer like Porsche would pride itself on its customer service.....well, you would until you remember who now owns Porsche.

I came quite close recently to going for a PHEV, and I did wonder about any possible effects of the petrol engine being idle for long periods of time. I was assured that it wasn't a problem, which Craig has confirmed as not being a problem for a BMW.

The other question about PHEVs, to which I haven't seen an answer, is the effect of the sudden need for a cold petrol engine to burst into life either through the driver wanting to accelerate hard or through the battery running out. Most of us try to treat a cold engine gently, but one can't in this case.

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Mon 8 Feb 2021 01:52
Porsche Cayenne e-Hybrid - Porsche Hybrid - edlithgow

OP, you can confirm oil dilution by fuel by getting an oil analysis done, IF you have a sample of the oil.

If its already been changed, its unlikely the dealer has retained a sample, and you wouldn't know it was genuine if they produce one anyway.

Bear it in mind for the future, if there is one,

Its a while since I looked into this but IIRC you should check that the lab uses gas chromatography to estimate fuel dilution. Some of them deduce it from the volatility and viscosity measurements which are less specific,

Edited by edlithgow on 08/02/2021 at 01:53

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Mon 8 Feb 2021 09:00
Porsche Cayenne e-Hybrid - Porsche Hybrid - kiss (keep it simple)

I would be more concerned by an engine only running for a short time than not running very often. A 30 mile trip for instance might result in the engine just being needed for the last mile or so. It could then be left for several days before repeating the process. This is the equivalent of many consecutive very short runs, which is not good news for the exhaust system.

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Mon 8 Feb 2021 10:02
Porsche Cayenne e-Hybrid - Porsche Hybrid - barney100

Sympathies with your problem. It seems German customer service leaves a lot to be desired, won't bore you with the details but Mercedes were almost rude with my car faults. How are BMW VW and Audi in the customer relations field or are most manufacturers dismissive?

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Mon 8 Feb 2021 10:20
Porsche Cayenne e-Hybrid - Porsche Hybrid - skidpan

How are BMW VW and Audi in the customer relations field or are most manufacturers dismissive?

When we had a 1 series the dealer was very good for the first 4 years but then moved into a fancy Gin palace and turned into a robber and liar. We got the issue sorted but never went back, luckily we had a good local BMW (Merc and Volvo) indy.

The Seat dealer we bought the Leon from was also a liar and a cheat. When they refused to sort out their paperwork problems (the car was actually fine) we raised it with Seat who accepted the problems and sorted them. They sent us a £200 voucher to spend on any product at any Seat dealer with no time limit, we had a set of tyres about 3 years later.

Not had any issues with the 3 Skoda's thus cannot comment.

Years ago VW were fine but when we had the last of 4 in a row the dealer sold out to a major chain and we had stand up argument with the body shop manager who accused me of damaging my own car in the car park despite the issue being with a part they had just fitted. Never went back.

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Mon 8 Feb 2021 11:39
Porsche Cayenne e-Hybrid - Porsche Hybrid - madf

I can recall petrol engines often gave problems if only driven very short distances. For example : out of garage, wash it, back in to garage.

The Rover 800s in the 1980s certainly would flood the car with petrol when next starting - and tthe solution was foot flat to floor on teh accelerator.

I assume all German car makers are liars : the law proves that..

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Mon 8 Feb 2021 11:50
Porsche Cayenne e-Hybrid - Porsche Hybrid - skidpan

I assume all German car makers are liars : the law proves that..

I assume that ALL car makers are liars - experience has proven that.

Mazda dealers have lied to me, Toyota dealers have lied to me, Volvo dealers have lied to me.

As of this exact moment Skoda have done very well except for the time I tried to buy a service plan for the wifes Skoda and the service team tried to sell me their own plan and not the genuine Skoda plan which they claimed to know nothing about (despite us having such a plan on the Superb and we had used it in the service dept). The dealer plan was quite a bit more expensive and tied you to that one dealer. After some discussion they spoke to sales who took over and sold me what I actually wanted.

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Mon 8 Feb 2021 12:06
Porsche Cayenne e-Hybrid - Porsche Hybrid - sammy1

I have never understood why you would buy a hybrid with only 30 miles or so range in EV and given the added complications of the set up. I have found this this morning while checking out OIL DILUTION in hybrids. It is worth a read

https://patents.google.com/patent/DE102013216215A1/en

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Mon 8 Feb 2021 12:58
Porsche Cayenne e-Hybrid - Porsche Hybrid - edlithgow

Pretty unreadable.

Rather badly written, vague, and with some obvious mistakes, probably because the authors couldn't read it either.

For example : " For example, even if the fuel is not old, oil dilution may occur when the engine is often cold-cranked to improve fuel economy." does not really make sense.

For example : " For example, when an increased engine oil dilution is detected while the vehicle is in an electric mode, the vehicle may be temporarily and deliberately put into electric mode even if continuous operation in the electric mode was possible and even if the engine mode was not requested by a vehicle operator" is just wrong.

It does support the idea that hybrids dilute their oil though, if you thought that needed support, and if you believe these authors. It is a Ford patent, so it presumably has credibility.

AFAICT (havn't read the whole thing) it assumes/estimates oil dilution based on usage pattern, rather than measuring it (an extension of some oil life monitor algorithms that have been around for ages), and responds to that by commanding the engine on, and running it hotter. They also factor-in fuel ageing.

I didn't notice any actual data on the prevalence or impact of either of these issues though, but if Ford thinks they are a problem I suppose they must be, unless they are mis-directing the competition with a techno-.scam.

Edited by edlithgow on 08/02/2021 at 13:21

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Mon 8 Feb 2021 21:49
Porsche Cayenne e-Hybrid - Porsche Hybrid - Brit_in_Germany

Ed- it is a German patent application translated into English by the Google computers. You need to read the original before you criticise the content.

patents.google.com/patent/US9403427B2/en

Edited by Brit_in_Germany on 08/02/2021 at 21:50

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Mon 8 Feb 2021 22:09
Porsche Cayenne e-Hybrid - Porsche Hybrid - sammy1

Yes read the English which is there to click on if you look.

Regardless it seems obvious to me that manufacturers of these Hybrids and other variations using a battery are aware of oil dilution by petrol and just not advertising the fact. Surprise surprise!

What would concern me if I owned one would be what damage is being done to the mechanical components in the sump swilling around with a mixture of oil/petrol. What are dealers noticing when they change the oil? I doubt many DIY are doing their own oil changes

What damage or wear has occurred in the OP's Porsche?

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Mon 8 Feb 2021 23:06
Porsche Cayenne e-Hybrid - Porsche Hybrid - brum

Yes read the English which is there to click on if you look.

Regardless it seems obvious to me that manufacturers of these Hybrids and other variations using a battery are aware of oil dilution by petrol and just not advertising the fact. Surprise surprise!

What would concern me if I owned one would be what damage is being done to the mechanical components in the sump swilling around with a mixture of oil/petrol. What are dealers noticing when they change the oil? I doubt many DIY are doing their own oil changes

What damage or wear has occurred in the OP's Porsche?

It struck me as obvious for some time now that phevs are going to be a big problem for some, particularly those that do charge them and typically do shortish town and back trips , a scenario that reviewers/manufacturers push as being ideal for phevs.

I may be mistaken, but from video reviews Ive seen, phevs in the default hybrid mode often fire up the ICE for very brief periods, sometimes seconds, when acceleration is required or the hill you're going up is a bit too much for the battery and then shut down. So the ICE suffers many start stops and little run time, never getting up to operating temperature. Bearing in mind that a CAT needs up to 5 minutes to reach operating temperature during which time the ICE runs very rich to assist CAT warm up. Stand outside a petrol engined car when its started cold, run a minute or two and you can smell the petrol fumes.

So no surprise about petrol dilution.

However I suspect, in the OPs case that the warning message was simply a warning to say it had disabled EV mode until the engine had a good run, at full temperature and evaporated off the fuel in the oil and eventually would have returned to normal, although that could take several hours of running the ICE.

I wonder if the increased CO emissions (not CO2) that constant cold running phases produced has ever been considered by the powers that be.

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Tue 9 Feb 2021 01:15
Porsche Cayenne e-Hybrid - Porsche Hybrid - edlithgow

What damage or wear has occurred in the OP's Porsche?

You might expect more wear, depending (mostly) on how low the viscosity gets. You could get clues to this from the metal content in an oil analysis, though a standard emission spectroscopy elemental analysis is a poor predictor of actual failure because it only sees tiny particles, not the larger fragments that generally precede failure.

Specific wear-debris analysis is more difficult, involving separation of particles by size, often on a magnetic gradient, and expert microscopic examination. Not cheap.

Some running-in debris is normal in any engine though, so you'd need data from the same engines run without oil dilution for comparison. This is unlikely to be available.

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Tue 9 Feb 2021 00:48
Porsche Cayenne e-Hybrid - Porsche Hybrid - edlithgow

I looked at the link provided. Don't feel too apologetic about that.

If tts a Google translate from German its actually not at all bad.

I'm not reading through all that again, but I note that, via the new link provided, the specific error that I noted is still there. so I doubt Google is to blame

Regardless of critique, I agree, and already said, that it shows Ford, at least, is aware of this problem, which is, after all, inherent to the way these things operate.

One would not expect them to discuss this (or anything ) openly since it might upset or confuse the punters. Patent applications are thus a potential source of information on enemy intentions, if you can stand to read them. Maybe the bad writing is a cunning plan.

Anyway, well done, 007. Carry on.

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