Have I just bought a lemon? (Possible diesel in engine oil)

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I've been looking for a new daily driver for a few months. I just bought a 2010 facelift RAV4 with full service history and in great condition from a local dealer. Lovely car! Only problem is I've just checked the engine oil and it's quite a bit above the max fill line.

That tells me that either the dealer, who just serviced it, overfilled it, or that the turbo is letting diesel into the engine oil.

What should my next move here be? The dealer seems to be very reputable. I'm hoping they won't just wash their hands of the problem. But what should I be asking them to do: take the car back and issue a full refund, flush the engine oil and refill to the correct level and see what happens, or get on with repairing the turbo?

Any help/advice would be appreciated.
 
Caporegime
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I’d probably give them a chance to rectify, you don’t need to reject immediately. Get them to do a drain, flush and refill and see how it goes for a few weeks. If the level increases then you’ve got your answer, if it stays as-is then great.

Of course there’s also the possibility they overfilled to mask an oil consumption or leak issue, but again that should become apparent if filled to the correct level and monitored for a few weeks.
 
Caporegime
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DPF regens can also cause diesel dilution as unburnt fuel ends up in the sump. Unlikely on a Toyota though (don't even know if that one has a DPF)
 
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I'm pretty sure it does have a DPF. I think all RAV4s after about '09 had them. The emissions info would definitely suggest a DPF as well.

Looking at the MOT it only did 7k last year, so probably not much motorway driving. Maybe that has caused DPF related issues? I'm just hoping there's a relatively easy fix for it.
 
Soldato
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If it's just been serviced, i'd say it's most likely that they've simply overfilled it, I wouldn't start panicking about needing to replace turbos or reject cars just on the back of a high oil level. As paradigm says, ask them to drain and refill to the correct oil level and monitor it after that.
 
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How would diesel be getting from the turbo into the oil? Diesel shouldn’t even be in the turbo to start with.

Apart from the level how does the oil actually look/feel/smell? Any sign of contamination from other liquids or are you just jumping to random conclusions?
 
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How would diesel be getting from the turbo into the oil? Diesel shouldn’t even be in the turbo to start with.

Apart from the level how does the oil actually look/feel/smell? Any sign of contamination from other liquids or are you just jumping to random conclusions?

Pretty much jumping to conclusions. Hopefully it's just an overfill. I suppose it's easy to do if the garage can't be arsed to wait for the old oil to fully drain out, and then they top up the required amount. I'm less than 1cm above the max level, which I suppose isn't that much?
 
Soldato
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You should double check you are checking the engine oil with the car at the correct temperature.

This recently caught me out new Golfs should have the oil checked with the engine cold, old Golfs were with it up to temperature and left for a few minutes.

It made a noticeable difference warm it was in the middle of max/min cold it was on minimum.
 
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How would diesel be getting from the turbo into the oil? Diesel shouldn’t even be in the turbo to start with.

Apart from the level how does the oil actually look/feel/smell? Any sign of contamination from other liquids or are you just jumping to random conclusions?
Lol if Diesel is in the turbo I would be a lot more concerned with it picking up and going runaway.
 
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Was the car on a level surface when you checked the oil? Even a slight gradient can cause erroneous readings.

You should double check you are checking the engine oil with the car at the correct temperature.

This recently caught me out new Golfs should have the oil checked with the engine cold, old Golfs were with it up to temperature and left for a few minutes.

It made a noticeable difference warm it was in the middle of max/min cold it was on minimum.

I checked it on my drive (slight decline), then again on a level surface. First time about an hour after a long drive. Second time about 5 minutes after a long drive. Reading seemed pretty similar both times: about 8-9mm above max fill line. I will check it when it's completely cold, although I suppose you'd expect a higher level then, as the oil drains fully to the sump?
 
Caporegime
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I’d be inclined to take it on a high ish engine speed run to see if you can trigger the DPF to do a regeneration or not, my old Focus had a similar issue (oil level was way too high when I bought it) so it got driven from jct 16 down to 15 of the M6 and back a few times in third gear (to keep the rpm high) and it seemed to do the trick, subsequently changed the oil and it was fine for the next 20k miles, I only did relatively short trips in it so once a month I did the same M6 run to trigger the regeneration.

It was quite smoky when I bought it also but a combination of using vpower diesel and the Italian tune up seemed to cure that too. :)

Failing that, get some professional advice, don’t start tinkering with the turbo if your mechanical knowledge makes you think it’ll have diesel in it....
 
Soldato
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I've been looking for a new daily driver for a few months. I just bought a 2010 facelift RAV4 with full service history and in great condition from a local dealer. Lovely car! Only problem is I've just checked the engine oil and it's quite a bit above the max fill line.

That tells me that either the dealer, who just serviced it, overfilled it, or that the turbo is letting diesel into the engine oil.

What should my next move here be? The dealer seems to be very reputable. I'm hoping they won't just wash their hands of the problem. But what should I be asking them to do: take the car back and issue a full refund, flush the engine oil and refill to the correct level and see what happens, or get on with repairing the turbo?

Any help/advice would be appreciated.

Just to clarify, you think the turbo is letting diesel into the engine oil.
 
Soldato
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When checking the oil level you should be able to smell the diesel on the dipstick. However as Django and a few others have said a turbo doesn't have diesel, it rotates due to exhaust gas pressure forcing more air into the engine
 
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Sounds like too many regens because of short trips/ city driving?

Possible, but surely that would only happen if regens were being interrupted? It would be strange for a car to be driven in such a way as to trigger repeated regens, but not for long enough for the regens not to complete. Could happen if previous owner had a shorter daily motorway commute, but then again the oil has been changed by the dealer since then.
 
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Got it checked out today by a local garage. They said the oil level was barely above max fill. They took a bit out. Couldn’t see any problems, so fingers crossed it’s nothing. They said sometimes the DPF regen process can elevate the oil level sometimes, but that it’s nothing to worry about if it does happen.
 
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This car is becoming more lemony by the day! Driving to work on the motorway this morning I get the check engine light. RAC guy comes out and diagnoses it as a problem with the fuel injectors:

DTC: P062D,No. 1 Fuel Injector Driver Circuit Performance

It also threw a "startability malfunction," but I read that that's usually a consequence of whatever the main fault is.

I managed to drive it back to the dealership and they've given me a replacement for now. Anyone got any experience with injector problems? Is it usually a big job? What should I be asking them to do? I'm worried they're going to bodge it so that it lasts long enough to get out of warranty.
 
Soldato
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I’ve a Vauxhall Vivaro van which is only used for local journeys. About once a year it throws up a “Check Injection” error due the DPF not getting a chance to kick in. I stick some Redex DPF cleaner into the fuel tank and take the van on a motorway run at 60mph in fourth gear for a good half hour which sorts out the problem. I don’t know if this is relevant particularly as you say you drive on the motorway but thought I’d throw it out there!
 
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