DJ not starting

[ceetee25]

Drove it home no problem parked it overnight.....next morning doesn't start. Turns over when you deactivate mobiliser for starter motor but nothing. Disconnected fuel pipe from tank and nothing comes out but connect pump and it draws fuel? Doesn't pass the pressure switch test either,(even though there is fuel present at the bulkhead fuel pipe connector) using pipe connected and a jumper to pos 87 fuel relay as per Haynes. Also there is no voltage on the + terminal 15 black wires (which go to a white resistor block underneath the coil then connected via a single wire to the coil) when the ignition is switched on. The coil primary cct measures more than the 0.5-0.8 ohms so suspect that for a start but with no voltage it still wont work anyway although a new original coil will be purchased. secondary winding is ok incidentally. Don't understand how this happens overnight! incidentally naturally there was no spark except when I ran a jumper from the pos terminal of battery straight to coil 15 and then I got soark at the plug. But if there was no running voltage from the ignition switch this obviously wont help.
So overnight suspects are fuel blocked from tank or possible ign switch that sends override battery 12 volt to coil and the coil itself? Its got me beaten temporarily but hopefully not for long when I look at the specifics.......however more than one head is better than one in my estimation!!
so confirmation
1 should I get voltage at the coil when ignition on
2 Should fuel flow out of the tank when pipe disconnected
3 What is the white ceramic block under and connected to coil....the lowering resistance?

[AdrianC]

Turns over when you deactivate mobiliser

Uh-oh... I hate aging alarms and immobilisers...

3 What is the white ceramic block under and connected to coil....the lowering resistance?

I'd be very surprised if it does have a ballast resistor coil on it. Pic?

So - when you turn the key, can you hear the fuel pump? It should fire up for a second or two to pressurise the rail. You say there's fuel at the rail, how much pressure? Proper high-pressure squirt, or just a bit of a dribble?

When you get somebody to spin the engine over, can you see a spark at a plug?

[PaulG]

Remake all of the brown earth connections to the body underneath the coil (about 5 of these), and all of the similar ones going to a bolt on the LH cylinder head (about 7 or 9 of these) - cut off and remake, don't just clean them, that's not enough! Remove the paint for the body connection, and emery cloth the aluminium on the cylinder head. Light smear of vaseline on connections if you like (oo-err!)

Cut off and remake the red wires connection on the back of the alternator. The thinner of these is your permenant +12v to your fuel pump and ECU / Idle stabilisation control relays. Any corrosion (i.e. resistance) in any of these will "cock" things up)

If no joy post back. No idea about resistor, my 2.1dj does not have one, might be PO (Previous Owner) Syndrome! Has the ignition system been mauled?

Hope this helps,

PaulG

[ceetee25]

Hi Guys
thanks for all this info. I have had to leave it for the time being but will be straight back on it soon with more time to spend. Have got new coil and petrol tank so I will work my way outwards from these.
The last owner was a Porsche mechanic and had fitted update coil, dizzy cap and leads which were non standard to the DJ so probably retro fitted the ceramic resistor as well. Not sure where the standard resistor is , if indeed there is one. Will repost when I have started and done all the stuff including the hints and repair advice.

[ceetee25]

Van now running after checking all items in the replies I had.
Conclusion is the ign coil had failed.
I say this because the only things that are now different are the new fuel tank and the ignition coil. Could have been the tank but ....who knows fuel came out of it when I drained it so assume the supply was good after all, that left the coil.
Anyway thanks for all replies.