I am experiencing an unusual problem with my 2006 S-TYPE R. and hoping for some input or suggestions.
It has recently started having issues starting from cold.
I will try to provide as much info as possible, apologies for the long post:
When turning the key, sometimes nothing happens, sometimes there is a mechanical 'clunk', sometimes it tries to turn over and occasionally, it starts.
Repeated attempts eventually get it to start, when it eventually does, it just starts as normal as soon as I turn the key, rather than turning over for ages.
Sometimes after it starts, it seems to run 'lumpy' for a while, other times it is as smooth as usual.
Battery is brand new and charged, I replaced the battery negative cable as a precaution, as the terminal clamp had 'cracked' (the fault was there prior to replacing the cable, doesn't seem to have made things better or worse)
The flap on the ignition barrel isn't sticking open, when I insert the key, the seat and steering wheel move to the memorised position.
The dashboard lights come on when I turn the key to the appropriate position.
Reading the fault codes after trying to start it reveal P0340 and P0345, which are camshaft position sensors for bank 1 and bank 2 (or wiring ?)
It has been suggested that it is very unlikely that both sensors have failed at the same time, more likely to be a common issue affecting both banks (possibly poor earth / grounding ?)
Once it has warmed up, it will repeatedly start on the first turn of the key.
A friend suggested connect a jump lead from a metal point on the engine to a good earth, to see if the engine earth strap was loose.
Thought that this had identified the issue when I tried it yesterday, as it subsequently started at least six times in a row (removed the key, locked the car, unlocked it, key in ignition, started first time)
It appears as though this wasn't the case, was only starting because I had already had it running, so must have warmed up enough.
Left it overnight, tried to start this morning and it didn't even try to turn over, immediately tried the jump lead trick but still wouldn't start (unless of course I wasn't getting a good connection at one end ?)
I think that at one point I have also seen a 'coolant temperature sensor' fault code, but it seems to warm up as normal, doesn't overheat or loose water.
So, poor earth, sticking starter motor or relay, faulty coolant sensor, ley lines, car parked on ancient native American burial ground, or none of the above ?