TD5 injection timing

[disco111]

Hello L.R. freaks in England

As I told you already I own a TD5 making year 2000 but as a technicien I have a smal question about the timing of the injection.

The engine as only one sensor on the crankshaft position and no sensor on the camshaft position,how does the ECU knows when to inject

because there are two TDC positions(one on compression with injection and one on exhaust whitout injection).Electrically there is no sensor

to inform the ECU about the position of the camshaft(compression situation).

The only explanation I can find is that the injector solenoide is energised each time the piston passes the TDC point,but on exaust situation

there is no fuel pression available(the lobe on the camshaft is on the opposite side).

Am I correct or if not what is the correct explanation? I don't like to drive something that I don't understand for 100%.

Thanks in advance from Gent Belgium

De Smet Martin P.S. see TD5 COLORS,paint is O.K.job finished.

[BogMonster]

From RAVE:

The CKP sensor is located in the transmission housing with its tip adjacent to the outer circumference of the

flywheel. The CKP sensor works on the variable reluctance principal, which sends a signal back to the ECM in the

form of an ac voltage.

The ECM uses the signal from the CKP sensor for the following functions.

• To calculate engine speed.

• To determine engine crank position.

• To determine fuel injection timing.

The CKP sensor works as a Variable Reluctance Sensor (VRS). It uses an electromagnet and a target ring to

generate a signal. As the target ring passes the tip of the CKP sensor the magnetic field produced by the sensor is

cut and then re-instated. The ECM measures the signal as an ac voltage.

The outer circumference of the flywheel acts as the target ring for the sensor. The flywheel is divided into 36

segments, each of 10deg. 31 segments have drilled holes and 5 segments are spaces. This equals 360deg or one

engine revolution. The 5 spaces correspond to the TDC position of the 5 cylinders. This allows the ECM to control

fuel injection timing for each of the cylinders.

[disco111]

Hallo

I do agree with your explanation,but we are talking about a 4 stroke engine so there are 2 rev's for 1 complete cycle.

The question his how does the ECU knows in wich stroke the engine is,the cranckshaft sensor gives a signal to the ECU each rev.

also when the engine is on the exaust stroke!!!On that moment there is no need for a fuel injection !!!

Do you understand what I try to explain?

Many greetings from Gent Martin.