Hyundai ix35 2011 cut power

lesleybamford

ive seen a number of blogs and watchdog threads about the Hyundai losing power in cold conditions.
i was driving tonight on the M5, I believe I hit 3000 rpm’s and lost power completely reading online talk of the fuel in the colder weather being an issue. I’ve seen a previous post here also reporting and talks of waxing relating to the fuel 

anyone else got the issue as surely this is an issue for others?

Bigwheels1111

Is it a diesel car ?.
I have had 20 diesel cars at least and never had waxing issues and that’s over the last 35 years.
Driven From UK to Germany on uk diesel in the winter, was -15 overnight and screen in car said -22 in the morning 
Vectra 1.9CDTI FIRED first time.
Do you have a basic obd2 scanner.
Might give you a hint in the right direction.

Bigwheels1111

https://forums.moneysavingexpert.com/discussion/5915862/car-losing-power-after-reaching-around-3000rpms/p1

Goudy

The fuel filter is waxing up.

In winter diesel gets all gloopy (clouds), to combat this at cold start/running diesel spill off (unused diesel from the injectors) which gets warmed going through the pump and rail usually circulates through the HP pump, rail and injectors than then back to the fuel filter, so when the engine is cold, it's trying to warm the gloopy fuel up quickly.
(A closed loop)

Once it's all hot under the bonnet this spill off usually then directs back to the tank and the hot returned diesel slowly warms up the fuel in there.
(An open loop)

Some manufacturers send this spill off back to the HP pump rather than the fuel filter, so in cold conditions than can cause the fuel filter to wax up as it's not getting warmed diesel through it yet.

If the fuel filter is a bit mucky and there's water in it which would likely be frozen (diesel fuel filters have a water trap in them at the bottom to trap any water in the diesel) it can restrict the flow of gloopy fuel through it causing power to drop off.

Most owners find changing the fuel filter helps in winter, I seem to think Hyundai stretched the service interval for this part (20k) but I have read there maybe an improved filter and filter housing to help combat this.

Diesel fuel filter can be a bit tricky to replace, it need priming first as any air in the new filter will cause air lock in the fuel rail.
Buy the best fuel filter you can (Bosch is the brand I always use) and get a local garage to swap it.
Some diesels have be fussy when fitted with cheap filters.

Ganga

I thought that modern diesel fuel does not wax up due to additives added in the refinery ,being retired  now when i used to work on construction equipment and it was only in the big freeze in the North East that i ever saw fuel wax up ,nothing you could do but put equipment in side and hope for the best. 

Goudy

Ganga said:

I thought that modern diesel fuel does not wax up due to additives added in the refinery ,being retired  now when i used to work on construction equipment and it was only in the big freeze in the North East that i ever saw fuel wax up ,nothing you could do but put equipment in side and hope for the best. 

Normal "summer" diesel starts to cloud or wax at around 0c and tends to get to a state where it can plug filters from around  -4c.

There are paraffin waxes in diesel to give the fuel high enough cetane (combustion speed) rating, they are normally liquid but it can crystalize if cold enough.

Winterised diesel moves that -4c plug point to around -12c. 
The processors add something called a distilled flow improver in winter.
It doesn't stop the crystalizing but helps keep the crystals smaller so they don't plug the filter.  

Trouble is, it's more expensive for the producer, it's also reduces the cetane rating and there are production issues, mainly it doesn't effect any crystals already formed in the fuel, so it's quite temperature sensitive to produce. 

The diesel ix35 seems to be prone to filter plugging in winter, even when the fuel is winterised.
I've never had the fuel system apart on one, so it's hard to tell why. 
Is it to do with how the fuel is looped when cold running so it's slow to self heat the fuel or is it just the location of the filter or it's condition. 

I've had common rails diesels that have been fussy to the quality of the fuel filter, which is why I suggested a decent brand (in my opinion). I also think it's wise to fit a filter made by the same manufacturer as the fuel system, like a Bosch.

I have ran older, none common rail diesels (Di's) on home made biodiesel and straight used cooking oil (pump timed diesels) and these almost always needed a heat before they ran cleanly in winter, or in the case of straight oil, heating pretty much all the time.

Some heaters use coolant, but that's no good when cold starting, other use a 12v sleeve around the filter but I would change the filter first, it's seem the fix for this until the next cold snap.