glow plug failure

[jimmyfoo]

HI, came to move my car (P reg 2.1 hdi saloon 98k) this morning to find it wouldn't start...., thought it may due to low fuel level & the funny angle car was parked at, so put a gallon in and pushed car off the kerb so it sat flat but still no joy then realised my glow plug light isn't coming on at all (had noticed this fri night but car started ok and ran fine coming home), have checked the fuses and nothings blown, have white smoke out of the exhaust so diesel is getting through but not igniting so am assuming its down to the glow plug system not working ? :-(......., can anyone help as am new to the world of 406's and am not sure where things are and what to look for ? :-)

[lozz]

Hi,
are you sure its a Hdi?

p-reg 2.1 thats Xud ithink

Hdi isnt Reliant on Glow-plugs,

[jonsowman]

Yep that'll be an XUD, and they really do need hot plugs to start. They will turn over forever and not fire otherwise.

I'd be putting new plugs in if it's not had them done recently, and failing that, check the plug relay.

[jimmyfoo]

Thanks jonsowman, i don't think the plugs are at fault as it started fine until yesterday morning..., and the glow plug light isnt coming on at all so am assuming its something else on the circuit for them..., where is the relay for them ? :-)

[jimmyfoo]

sorry loz, yep its an xud lol....., as i said am new to the world of 406's, have only had the car a couple of months

[steve_earwig]

Dammit, I just spent an hour writing a reply, hit go and the board ate it

P reg makes it a 1996, so that's seriously low mileage for a 16/17 year old car

I checked, the glowplug light is run off of the glowplug control box (see diagram http://peugeot.mainspot.net/wiring406/p8c.shtml ), so this is probably at fault (not happy about saying that as it could be a wiring fault, a coolant temperature sensor fault or any number of things, but I reckon this is favourite). It's located somewhere under the battery tray AFAIK and looks like this http://www.autoelectricalpartsuk.co.uk/ ... 13319.html . I've no idea about testing it (too many wires!) without some diagnostic, but check the connector for green furry stuff etc. first.

[midsmike]

Nope its 1997 they only made 2.1 in 1997 and 1998 that is low miles when i got mine just under 2 years ago it had 61k on the clock and that was low now it has 104k on it witch is still low

[jimmyfoo]

its a '97 P reg...., 2.1td 12 valve ;)

[steve_earwig]

Well I don't bleedin' know, I lost interest about 1990 so I was only going off Swansea Anyway all this prefix and suffix stuff is pretty meaningless outside the UK.

Your engine is the excellent XUD11BTE (aka P8C) and long may it live!

[jonsowman]

Few things you could try:

If you get a voltmeter, watch the voltage between the plug end and ground whilst someone turns the ignition on. If there's no voltage then I think it's almost certainly the plug relay has failed, which is underneath the air filter IIRC.

You should see about 10-15 seconds of voltage applied to the plugs (not related to how long the dash light is on for!).

If voltage isn't getting to the plugs, get a jump lead and manually attach the plugs to battery positive for about 10 seconds, then turn the engine over, disconnect from the battery as soon as it fires. Be careful not to short anything. If this works, it's definitely the plug relay or wiring.

[jimmyfoo]

Few things you could try:

If you get a voltmeter, watch the voltage between the plug end and ground whilst someone turns the ignition on. If there's no voltage then I think it's almost certainly the plug relay has failed, which is underneath the air filter IIRC.

You should see about 10-15 seconds of voltage applied to the plugs (not related to how long the dash light is on for!).

If voltage isn't getting to the plugs, get a jump lead and manually attach the plugs to battery positive for about 10 seconds, then turn the engine over, disconnect from the battery as soon as it fires. Be careful not to short anything. If this works, it's definitely the plug relay or wiring.

cheers for that jon, was going to get the voltmeter out anyway (just waiting for wife to get up to help) as am thinking on the same lines as you..., don't think it's the plugs themselves as i've not had trouble starting before.., plus the plug light not coming on to points elsewhere in my mind. Someone has mentioned the plug control box...., is this the relay by another name or a separate component ?

[jonsowman]

I'm pretty sure it's one unit called by various names including "glow plug controller", "glow plug relay", or the ever-verbose-Servicebox "pre-heat box":


This corresponds to item 1150 on the wiring diagram Steve linked to, which appears to only have connections to the fusebox/ground, the injection ECU, and the plugs themselves. It also shows the connection to the instrument cluster and the illumination lamp (V1150). I'm not sure if the plugs and pre-heat warn are driven from the same physical relay inside the box, but the evidence so far appears to suggest they are.

[jimmyfoo]

Cheers jon, looks like we thinking on the right lines...., am back up and running now......, got nothing on multimeter from the plugs, put a wire straight from the battery to the plugs for 10 seconds and she fired first turn of the key !! ...., looks like i'm off shopping for a new relay tomorrow lol

[jonsowman]

Good work, that is almost certainly the problem then.

Haynes says on 2.1 models, the glow plug relay is "on the near side of the engine bay, on a bracket beneath the accelerator pedal position sensor". It recommends removing the "air cleaner assembly and intake ducting" to get to it. There are two nuts holding the relay to its bracket. From the pictures, access looks reasonable once the air intake stuff is out of the way.

Good luck, let us know how you get on

[lozz]

sorry loz, yep its an xud lol....., as i said am new to the world of 406's, have only had the car a couple of months

no need to apologise, just thought id point out, you may have the Xud engine,