Cranking but not starting - Intermittent

[Psmith67]

Hi

I have a MY2020 1.2 Puretch 5008 that intermittently will crack (turn over) but not start unless I switch everything off, exit car, lock then unlock car, enter again then starts!

I have replaced key battery, new spark plugs and cam sensors but no change. Battery also has full charge and is healthy.

This happens randomly.

Anyone with an idea what might be wrong?

[wurlycorner]

That wouldn't be related to spark plugs and likely not cam sensors either.
Have you had a diagnostic reader on it to see if any DTC's stored, or to monitor signals while cranking? (fuel pressure, cam/crank signal etc.)?

[PaulC5]

When it does this, before going through the door locking process, if you leave the key in the ignition and open the door does it give a warning - if not then the immobiliser might not be recognising the key sometimes. Does it also happen with the spare key ?

[Psmith67]

Thanks for replies.

No DTC codes at this time or later. Did have a DTC about a month ago which was P11A9; cleared, changed Cam sensor and nil since.

Alarm sounds when open doors with engine running. Unfortunately no spare key

Whilst it is intermittent it is random too.

[GaryD1978]

Did you sort this? I have the exact same and know of others aswell.
I believe it’s the steering lock control module as it’s part of the immobiliser system.
If I put the steering lock on then it starts fine once released but if I don’t put the steering lock on then it’s sometimes cranks but won’t start unless I step out the car and back in which I believe resets the unit hence the start

[Psmith67]

Not tried that as the steering is almost all but impossible to move until the car has started. Still get started by exiting car, lock, wait, unlock, open door and stats without fault.

I did replace the aerial for the keyless start and that has not fixed the problem. Next step is to replace the brake pedal switch but will try the steering lock.

Then it’s off to a car spark to get the ECU/ BSI repaired/ replaced.

I have never come across such a problem in a car before.

[GaryD1978]

I had 3 non starts on Monday,
Then started to use the steering lock and it’s been fine up until today when my mrs forgot to put the steering lock on when she got out the car and when she returned, it wouldn’t start. I’m certain it’s the steering lock control module as it sends the signal to the ecu that the car can be started or not and if the release switch is faulty then it may not start

[PaulC5]

If you put some magazines under the front wheels the steering will be easier to turn with the engine off.

[GaryD1978]

Back to the drawing board as had another cranking non start today and that’s after putting the steering lock on etc.
It’s booked into the auto electricians a week on Wednesday to try and solve

[PaulC5]

If your auto electrician is not a Peugeot specialist you might be better off going to a Peugeot dealer.

[GaryD1978]

I agree. There is a Peugeot dealer opposite to where I work so will get it booked in.
I have 3rd party warranty on the car and they have been great so far so will get it booked in and hopefully they will cover it

[GaryD1978]

Car booked in on Wednesday at the dealer. In last week I've noticed far less no starts when using the steering lock. Also noticed the engine can cut out, 1-2 seconds after starting. Will update

[GaryD1978]

Car was at dealer today.
No issues or fault codes found.
Car was normal and as they expected.
Cannot fix something that’s not broke I was told.
Nothing more I can do with this now

[wurlycorner]

Frustrating, but yes unfortunately it's very difficult to trace intermittent faults on cars when they aren't in fault mode.