406oc.co.uk

Hello,

have noticed a starting issue recently. The car is a 406 Hdi 90 hp from 2003 so I would usually just go through the pre warming process for the glow plugs just once, so just turn the key wait for a few secs ànd then turn key fully to start but sometimes now I have to do this two or three times before the car will start. If when I turn the key just once after pre warming sometimes the engine does not turn over just silent, it is not doing it all the time just now and then. It did it recently after a 140 Mile run and a couple of times on recent cold mornings. Is this due to Glow Plugs? I asked a garage a couple of years ago to change them but they only changed two. They said the others were still OK, so I still have 2 original glow plugs. Or could it be something else, the battery is fairly recent, so I'm sure it's not that. The coolant temperature sensor was changed recently.

Thanks for any advice.

HDi's will normally start in the coldest of weather without waiting for the glowplug light. Faulty glowplugs are more likely to cause initial uneven idling than failure to start.
Failure to operate the starter is probably a bad connection or worn ignition/starter switch.
Also worth checking the fuel priming bulb under the bonnet hasn't gone soft overnight - does it start better if you pump it back up?

I'm thinking ignition switch too - have you had problems with your blower working intermittently?

As Doggy says, the Hdi doesn't really need glow plugs to start the car, and as yours is a 90 the chances are you have the priming bulb.

The CTS can cause issues but if yours is new then it should be okay

Ignition switch, starter cranking speed and low residual fuel pressure/air in fuel line are the things that most commonly cause difficult starting. You could actually disconnect your glow plugs and engine would easily start unless ambient temp was below freezing.
Given your starter sometimes fails to react, my money is primarily on ignition switch and then maybe starter motor itself.

Hello,

Thanks very much for the replies. If the problem is the Ignition Switch.

Please excuse my ignorance, but is the Ignition Switch a component within the Ignition Cylinder / Barrel?

Can the Switch part just be changed, or will the whole Ignition Cylinder / Barrell have to be replaced as well as involving a new set of keys?

I've not really been using the blower as the weather has been so mild recently. The car was not used for about 18 months, just started using it again.

Also, can anyone give me an idea where the priming bulb is located on Hdi 90 engine? Had a look but couldn't locate it.

It seems at present to be an intermittent problem, the car will start just have to attempt starting a couple of times. Just worried it could get worse or eventually fail. The car has 138 k miles. There's a bit of wear on the original key.

Thanks for your help.

Fear not - the ignition problem ( if it is indeed the problem ) is only a part of the harness that fits to the back of the barrel - your existing barrel and key are unaffected.

Hold on, I'll find a link to what you are looking for..
https://www.ebay.co.uk/itm/Ignition-Swi ... 635-2958-0
The white part fits on the back of the barrel, the other bits fit to connectors under the steering column cover.

I replaced this on my wife's old Picasso and on an old 406 - it's fairly straightforward.

To remove the ignition barrel switch (white part pictured above ) you'll need to insert the key, turn to position 1 and press a little tab on the underside of the barrel - you'll need to remove the steering column covers first.

The priming bulb looks like this....
https://www.ebay.co.uk/itm/Used-Genuine ... 634-2357-0
It'll be towards the left of your engine cover if memory serves me right - it's been a while since I've owned a 90.

@ Ginger Magic

Cheers! Much Appreciated.