Morning all,

Recently acquired a Mk6 1.4, relatively low mileage super clean etc. The issue is an intermittent start problem.

I turn the key, dash lights up properly, turn it further and starter clicks but no crank. Happens maybe once a week, doesn't make a difference if it's just been turned up or sat for a couple of days. Bumps fine and once bumped it'll start easily on the key every time.

It's got new battery, new Bosch starter, new ignition switch, switched out start relays and it still left me non starting this morning.

I'm stumped, has anyone got a clue? At this point I'm starting to think immobiliser but no idea where to start there.

It might have a new battery but is it fully charged?

Also is it securely connected?

Check the main battery earth to the body is also clean and secure

16 minutes ago, DaveT70 said:

It might have a new battery but is it fully charged?

Also is it securely connected?

Check the main battery earth to the body is also clean and secure

I'll admit I haven't checked, I assumed as it was relatively new, the battery doesn't die (it can drive for a couple of weeks starting several times a day and not happen) and the problem is so intermittent it was more of a physical fault, I'll get my multimeter from the yard and check later on though! 

1 hour ago, Jack of all legs said:

I turn the key, dash lights up properly, turn it further and starter clicks but no crank

Well if the starter motor is new and not faulty, and the battery is in good condition the problem is likely a damaged ring gear which prevents the starter motor from engaging.

2 hours ago, unofix said:

Well if the starter motor is new and not faulty, and the battery is in good condition the problem is likely a damaged ring gear which prevents the starter motor from engaging.

Ouch, haven't even considered that, good shout though.

1 minute ago, Jack of all legs said:

Ouch, haven't even considered that, good shout though

Easy enough to test.

Next time it won't start, with ignition OFF put the car in third gear and rock the car backwards and forwards a couple of times. That will move the ring gear. Then try and see if it starts.

Update for anyone still following. went through all the earths today and although they looked okay I can't say they were getting a good connection, voltmetre was giving me sporadic readings but cleaned them all up and now getting 0.2ohm between battery and starter. Battery was sitting at about 85% so that's on charge too just so I know all is tip top. Will update if it happens again but hoping it was just a crappy earth!

If the resistances were more than that (0.2 Ohms may be OK) you may be on the right track.

Do let us know...!