Thread: So the PUMA goes back to the garage again tomorrow

The D/gas system on my Tdi doesn't feed gas in until the coolant temp is over 45 degree's,Why? because the engine will knock,once again why? because the engine isn't hot enough to give complete combustion,you get detonation instead of burning.Back about a hundred posts I mentioned that the software fix is probably nothing more than the ECU not letting the fueling or timing increase until the temp has reached a point where even combustion is garanteed regardless of throttle position.All of the puma owners have the same trouble,the engine rattle and all of you have it not at start-up but half a mile down the road,right where your getting into traffic and putting your foot down,the ECU doing what it's told and dumping hot fuel into a cold engine. Pat

Just one more thought here why this still may be water related. Cooler temperatures will cause water to condense ... with higher temps that water is suspended in air as vapour. From reading this thread, this problems seems to be particular prevalent shortly after a cold start on colder days, ergo ... just my 2c worth.

I have previously thought whether there could be cold weather condensation in the fuel line downstream from the filter...

But condensation happens from air I thought... it's when the air can no longer hold the moisture. The only place there should be air is in the tank??

From talking to Shell technical - apparently water can be held in suspension in diesel and then condenses out in colder weather. The Australian standard for diesel allows for up to 0.05% water - which on 1000l is 500mls.

Diesel fuel unfortunately is isotopic so it does attract moisture.The reason that it is taking time to fix this problem is because I believe there is more than one reason for it happening.I also believe it is the knock sensor and not the fuel valve that causes the engine to go into limp mode. Pat

Originally Posted by PAT303

Diesel fuel unfortunately is isotopic so it does attract moisture.The reason that it is taking time to fix this problem is because I believe there is more than one reason for it happening.I also believe it is the knock sensor and not the fuel valve that causes the engine to go into limp mode. Pat

I bet if it was a problem with a D3 or RR,it would be well & truly sorted by now.

It appears they (LR) are stalling on the problem.

Hasnt happened on juniors Puma yet & its been pretty cold here

The cold air/condensation theory is a possibilty. Ian and I discussed this briefly a couple of weeks back. What isn't consistent is the regularity of the occurence. On the two times this has happened to me it was cold and dewey. For me there have been many mornings like that without it happening? For Ian and Lou it is frequent however.