How to resolve the P1340 trouble code?
2 Answers
P1340 trouble code solution is as follows: 1. The meaning of the "P1340" trouble code: Incorrect installation of the timing belt and camshaft chain, resulting in incorrect valve timing, causing the engine speed sensor G28 and camshaft position sensor G40 signals to be out of sync. 2. First, check the timing belt. If the belt is normal, remove the valve cover to inspect the camshaft chain. Align the timing belt marks, then observe that there is a notch on the inner edge of the exhaust camshaft sprocket that should align with the triangular mark on the last bearing cap. The intake camshaft mark is the same as the exhaust mark. 3. Then count the number of links between the two camshaft sprocket marks, which should be 16. (This fault must be resolved, otherwise it may lead to mechanical failure of the valve train).
A few days ago, my old Passat showed this P1340 code, which scared me into checking the information immediately. This fault code indicates a misalignment between the camshaft and crankshaft positions, commonly caused by timing chain skip or sensor malfunction. I first opened the engine hood and touched the timing chain cover—it was scalding hot, which didn’t feel right. I drove it to a familiar repair shop, where the mechanic used a diagnostic tool to check the data stream and directly concluded that the timing chain had stretched. Upon disassembly, it was indeed off by three or four teeth. Replacing the new chain and tensioner cost over two thousand. My advice is not to push your luck if you encounter this issue—severe timing misalignment can lead to valve damage, and the repair cost won’t be small then.
