TDI Charger Temp Logs: 96kW Engine Data

Hello,

zum Vergleich mit meinen Werten wüßte ich mal gerne die LLT anderer 96kW-Wagen (Golf 4, Passat . . .) im Bereich von etwa 4000 - 4500 rpm bei BAB-Tempo (4. oder 5. G(angling).

If necessary, a full-throttle acceleration in 3rd gear to around 4500 rpm will also do the trick; at least, my car reaches practically the same maximum temperatures as it does on the highway - although the temperature reading only shows this about 2 seconds after releasing the accelerator.

I find it most informative to record the data from sensors MWB 007, 008, and 011.
Then you can see the LLT (Low Load Torque), boost pressure, and excess air (calculated as a potential additional injection amount: soot reduction minus torque output) at a glance.

I would also be interested in the coolant temperature (also found in the main control board, module 007) to see if my 100°C reading at an outdoor temperature of around 10°C is perhaps a bit high compared to other systems.

Hello Ulf,

While there are no logs available, here's a bit of reasoning:

Maybe someone else has already mentioned this, but in my opinion, your intake air temperature is too high.
I'm treating the air as an ideal gas and calculating the static mass of the air in the intake manifold, which should hopefully be proportional to the amount of air that enters the cylinder. (assuming similar flow rates for 110hp / 130hp TDI engines).

from pV=nRT --> n = (pV) / RT

Now, let's consider the ratio of two different systems: the intake manifold from the 110 hp engine with 1.1 bar and a low-temperature limit (LLT) of 50°C, compared to yours with 1.3 bar and an LLT of 100°C.

n1 / n2 = [(p1 * V) / (R * T1)] / [(p2 * V) / (R * T2)]

n1 / n2 = (p1 * T2) / (T1 * p2)

This quotient therefore describes the ratio of air filling in the cylinders of "my" engine compared to "your" engine.

with
p1 = 1.1 bar, T1 = 323 K
p2 = 1.3 bar, T2 = 373 K

results in n1/n2 = 0.98

That means your engine effectively has only 2% more air in the combustion chamber than the ASV.
and that's with an extra 20 or more horsepower.

Da kann doch was nicht stimmen! Or what?

Critics are welcome; I'm almost certain that this whole thing can't be viewed so simply.

Regards,
George.

Georg_G wrote:

now the quotient of two different systems, namely the intake manifold from the 110 hp engine with 1.1 bar and 50°C LLT, and yours with 1.3 bar and 100°C:

Hi Georg,

You've got something mixed up there.
My maximum coolant temperature was 100°C, with the lowest level temperature (LLT) previously being a maximum of 80°C.

Tomorrow I'm going home... I'll probably post something then.

ulf wrote:

You've got something mixed up there. 100°C was my maximum coolant temperature, and the lowest level temperature (LLT) has been a maximum of 80°C.

Oh...
Quick shot.

George.

So...

Last Friday, I started a small test drive with my A4 in an outdoor temperature of about 34°C. Everything was logged. Unfortunately, there was a lot of traffic on the road, so I couldn't fully utilize the vehicle's capabilities.

Conclusion:

- At a constant speed of 100 km/h in 5th gear: 42.3°C intake air temperature.
- at 120 km/h: ' : 43.2°C charge air temperature.
- 15 minutes of idling at a standstill: 48°C charge air temperature.

Full acceleration from 3rd to 5th gear (52 km/h to 187 km/h): Intercooler temperature 50.1°C -> 65.7°C.
'from 39 km/h to 208 km/h: Charge air temperature from 50.1°C to 68.4°C.'

Maximum charge air temperature: 68.4°C.
Maximum coolant temperature: 96.3°C.
Maximum diesel temperature: 90.0°C.

'It put a strain on the machine. Normally, the coolant temperature hovers between 86 and 90°C, the diesel engine runs at 70-80°C, and the charge air is between 40 and 50°C. The oil warmed up and stayed within the range of 88 to 89°C.'
When driving at high speeds for an extended period, all temperatures tend to decrease slightly again.

'@Ulf: After I've driven 2 people (including the boss) crazy with this damn CSV file, I'll send you the file via email if you want it. Please PM me with your email address. '

Julian wrote:

Last Friday, I started a small test drive with my A4, in an outside temperature of about 34°C. Everything was logged. Unfortunately, there was a lot of traffic on the road, so I couldn't fully utilize the vehicle's capabilities. . .

Hi Julian,

Thank you for your support!

I'm definitely interested in the log; please send me more details via private message.