2005 Volkswagen Jetta 2.5L Code P1340 | 17748 Timing Chain Problems

If you own or are repairing a Jetta 2.5L with code p1340 | 17748 be very careful with your testing and repair. Normally the code is set due to failing timing chain tensioner, broken timing chain guides or stretched timing chains. Occasional we run into this code due to a failing camshaft position sensor. But we ran into a strange one today. This VW has been to several other repair shops and has had camshaft and crankshaft position sensor replaced for over $600 with out any luck. The Check Engine Light comes right back on and it continued to idle rough. During the testing at the last shop it stopped running all together. If the steps below were followed the customer could have saved a lot of time and money:
P1340/17748 - Crankshaft/Camshaft Position Signals Out of Sequence

1. With a factory compatible scan tool:

A. Select Address Word 01-Engine.

B. Select Function 08-Read Measuring Value Blocks (MVB).

C. Enter Display Group 093. The 4th Display Field will show the timing of the engine. It should read 0 degrees +/- 5 degrees.

D. If the value is outside of specification, a timing chain timing issue is indicated.

2. Special tools T40070 Camshaft Locater and T40069 Crankshaft Locking Pin are required for verification of proper timing and installation.

A.There are no timing marks for the chains. The camshaft locater and the crankshaft locking pin verify the timing.

3. A visual inspection of the timing system will be required to determine why the engine is out of time.

A. Look for damage to guides and tensioners.

B. Look for evidence of lack of lubrication.

C. Look for slack in the timing chains.
We removed the valve cover to make sure the timing chains are timed properly (tool kit shown below) . With the valve cover removed we rotated the engine and found that the intake camshaft was not turning but the exhaust camshaft was. We removed the engine and found that the bolt holding vanos to the intake camshaft had come loose. In fact when the timing cover was removed the timing chain and vanos fell off (see picture). We installed the timing chain and timed the camshafts using the camshaft lock down kit. We performed a leak down test and found that all the cylinders had bent exhaust valves. Previously we could not properly perform a leak down test without having the camshafts timed properly.