A Jetta 5 8v 2lt came in for engine noise, what I found was that one Hydraulic lifter top was missing – the lifter is part of the follower, it is one unit, see the photo below. It is an easy job we replace the lifters and camshaft and it is a good practice to replace the oil pump also. This car has 410000 km on the clock and replacing the oil pump will be a good thing. But after we have done this the engine does not want to idle, the engine cut out and does not want to idle at all. I plug in the VAG scanner and the following code was logged:
1 Fault Found:
16492 – Manifold / Barometric Pressure Sensor (G71) / (F96)
P0108 – 001 – Signal too High – Intermittent
I have cleared the code but it comes back immediately, so that tells me there is a permanent fault. My next step was to unplug the sensor to check the wiring and voltage. To check the voltage at the wiring side do the following:
1. Pin 3 the voltage should be closed to 5v
2.Pin 1 voltage 0 -.02v
3.Pin2 voltage should be .5v
4. Pin Check this wire to the ECU for continuity
If all these checks have been passed, my next step would be to use a scope to check the sensor operation.
Actually, before I have done these checks I notice that there is something wrong with the wiring, one wire is completely broken off and the other 3 looks like something is eating the wires. See the image below.
Well after reconnecting the wire and securing the other wires the fault is fixed.