ford c-MAX 2.0 tdci iv ghia - soot and oil on caravan

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Mon 23 Aug 2010 22:17
ford c-MAX 2.0 tdci iv ghia - soot and oil on caravan - LeeWye

When we tow a caravan with the car I have always noticed that after a long jouney 4 hours small flecks of a sooty oily substance all over the front of the caravan. The issue as gradualy got worse until now the flecks are noticable after 30 mintues and after 4 hours the caravan is covered in the material.

The car has been to a few garages and all have looked at the car checked the emisions and test drove the car and said there is nothing wrong, but it is now impossible to tow the caravan.

In recent months when using the car with a full load I have noticed a clear oil on the back of the car. Also when you look at the exhaust compared to two other 2.0 tdci mondeos I drive the end of the exhaust is much blacker.

Another observation about the car is that the normal fuel consumption has gradually gone from the high 30's to the low 30's. When you touch the material on the car it feels like very thin oil with small pieces of soot in it.

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Tue 24 Aug 2010 10:29
ford c-MAX 2.0 tdci iv ghia - soot and oil on caravan - craig-pd130

How old is the C-Max? Does it have a DPF?

It sounds to me like it's an older version without a DPF, so the caravan will get a bit sooty, especially under fully-laden conditions.

The fuel consumption could simply be a blocked airfilter that's due for replacement, but it could also be a small diesel leak.

I believe the 2.0 TDCi engines use a fuel cooler (a small radiator to help reduce the fuel temperature as it returns to the fuel tank), because the tremendous high pressures generated by the diesel common-rail pump heats up the fuel.

This could have a pinhole leak. Drops of fuel would then get caught in the airflow under the car. However, this would also cause a strong smell of diesel, I'd imagine.

As I say, I **believe** the 2.0 TDCi motors use a fuel cooler, but you'd need to check if yours actually does. If so, can you find out where it is on the car and maybe place some cardboard etc underneath overnight to see if it drips?

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Tue 24 Aug 2010 10:49
ford c-MAX 2.0 tdci iv ghia - soot and oil on caravan - StanTheMan78

It's without a doubt diesel fuel you are finding, and it MUST be a fuel leak! I'd check the fuel tank for loose pipes. The fact that youy are finding it at the rear end of the car indicates that it's most probably not fropm the engine that it is leaking. What puzzles me is the fragments :/

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Tue 24 Aug 2010 23:18
ford c-MAX 2.0 tdci iv ghia - soot and oil on caravan - LeeWye

I belevie the fragmants must be from the exhaust as the end of the exhaust is much blacker than two other ford I drive with the same engine.

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Tue 24 Aug 2010 23:15
ford c-MAX 2.0 tdci iv ghia - soot and oil on caravan - LeeWye

The car is a 55 plate with the euro iv version of the engine..

There is no smell of diesel from under the car and there is no sign of a leak.

When looking under the car the spots oil under the car is no further forward than the rear suspension.

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