From Ross-Tech Wiki
17748/P1340/004928 - Camshaft Position Sensor (G40) / Engine Speed Sensor (G28): Incor. Correlation
- Timing Belt/Chain incorrectly installed
- Timing Chain probably lengthened
- Camshaft Position Sensor (G40) faulty
- Engine Speed Sensor (G28) faulty
- Check Timing Belt/Chain installation
- Use Measuring Value Blocks (MVB) to Check Timing Chain
- Check/Replace Camshaft Position Sensor (G40)
- Check/Replace Engine Speed Sensor (G28)
- When found in the 1.8T engine, check engine oil pressure. The oil pump pickup may be restricted.
- When found in the 1.8T engine (possibly others too), check to make sure the correct G40 is installed (single gap versus 4 gap).
- When found in VR6 4 Valve (BDF, BJS, BAA,) engines in conjunction with 17755 please see Technical Bulletin 15-07-03. The previous Technical Bulletin number was 15-04-01.
- When found in a 30-valve V6 gasoline Audi engine (such as EPB or BEL), DTC 17755 may be stored as well. If both of these codes are displayed simultaneously, and the codes only appear after the motor is revved above 1800RPM, then the issue is likely that the cam chain tensioners were installed on the incorrect heads (drivers' tensioner on passenger head, etc).
- On engines with chain driven intake camshaft(s), but belt driven exhaust camshaft(s), verify the number of chain roller links between the intake and exhaust camshafts is correct. Click on thumbnail to enlarge: