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- CX5 Akera 2.2 Diesel
Hi garycar
Just wait till you get the Skyactiv diesel in the U.S. You will need to check the oil level each week for the oil level rise as a result of unburnt fuel being returned to the engine due to DPF regeneration. As soon as the oil level gets near the "X" mark on the dipstick ( or the oil warning light appears) you have to have a full drain and refill with fresh oil at your own expense or if Mazda is feeling particularly kind on that particular day have it done for free. It's not covered as a warranty requirement. (At least not in the UK).
Jonno21
The fuel in oil on diesel models was addressed via a software update about 3 years ago.
I'm onto my second CX5 2.2 diesel and have never had an issue with "making oil". The first was a 2013 GT, and my current is a 2015/16 Akera.
My brother has a 2012 CX5 GT diesel and he initially had the issue, but since the sw update no further problems on a car that is 90% driven around town.
Re the issue of the 2.5 petrol engine "making oil", it just seems to me a big stretch that so much fuel gets past the rings that it dilutes fuel really quickly and by such significant amounts. If the rings were that bad or the engine was being overfuelled so much, then surely, the car wouldn't run at all well.
I think there is a fair chance that the problem lies somewhere else. I would be looking at any part of the entire fuel system where fuel can physically get into the crankcase. Fuel pumps, emission system, and any related lines that vent into the crankcase.....
Let me tell you my rationale for this - I run Suzuki 4 stroke outboards and am a mod on their forum. It's quite common to hear of this "making oil" issue on that forum, and, like here, most people point the finger at blow-by due to engines that are run for long times at idle speed of just above. Lots of guys troll lures and baits for hours on end with the engine just idling along.
But the real cause is quite simple in 95% of those cases, there is a tube from the VST that is part of the emissions system and is designed to take fuel vapour from the VST to the crankcase, but when the VST float is badly adjusted, or the needle is stuck, fuel level in the VST gets excessive and guess where that excess fuel goes? Yep, straight through that vapour tube and into the crankcase. The usual root cause is dirty fuel causing a blockage in the VST.
The other 5% were from crank driven fuel pumps that corroded and then leaked fuel direct into the crankcase.
Now, that exact situation may not arise for the Mazda engines, but fuel getting into the crankcase from some element of the fuel system or evaporative emission seems far more likely than massive amounts of fuel getting past piston rings to me.
Just a thought.....
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