k-jectronic fuel,problem

[dubsweeper]

I meant to jump the connector with wires not to chop it all about.

The coil being bad wouldn't stop the pump working if it was still in circuit. It just wouldn't fire. The pump would run when you cranked the motor.

Gavin

but there is no priming when i turn the ignition , the coil has nothing in it as its fried and thats where the middle plug has to go from the distributer cap , im lost now

[Jmac]

Yeah what if the coil is getting no power to it, then nothing else will work, i would try and hot wire it mate, to rule out the ign switch, beats the guesswork. Then you could rule out the ign switch. Then check your fuel pump relay, if the ign swithc is faulty then the relay wont get 12v on ign cycle. Bridging the fuel pump relay will only confirm if the pump is ok
Cheers
Jmac

[h100vw]

The pump will prime as you switch the ignition off. Regardless of the coil.

You have pick up in the dissy which triggers the ignition amplifier. The amp is what switches the coil on and off. This is the green or black wire if I remember correctly. The other wires on the coil are red and black I think.

Switching the current on and off in the coil primary windings is what causes the high voltage juice from the secondary windings and out the centre of the coil.

So I think even if the coil windings are open circuit, there is a good chance that the pump will be triggered.

I have the MK1 Haynes manual, so if you drop a coil in it and it doesn't run I can help you troubleshoot it.

Gavin

[Jmac]

Typo Gav ign on mate. Red black is pos side of the coil and green is the trigger side. Totally agree the pump will prime on ign cycle so if its not priming then you are not looking at an ign coil fault but more likely a fuel pump relay fault or wiring to the relay, fusebox or wiring to the pump.
Good luck,
Jmac

[Jmac]

hey dubbers , this is the problem now !!!!
my mk1 wont start ?? when i turn the ignition i can not hear the fuel pump turn on (the buzzing noise) from near the air filter k-jectronic, i know i have a stuffed ignition coil as well but that wouldnt make a difference ! i did have a problem with the key ignition switch behind the barrel , but have to jiggle and hold down the back of it to try and start the engine !!!
i have checked all fuses ect .... any ideas ?

Fuel , Air and spark at the right time and it will run. get a spark mate as it wont run without it anyway, then suss out your fuel pump power issue, tracing your fuel issue will still leave you needing a spark take your pick , you will need both and at the right time no question
Jmac

[dubsweeper]

woo hoo , cheers for the advice fellas !! just have to leave it for tomorrow too much input , this mk1 has just got a load of s### wire running through it , there is no sign of the pump ,priming solenoid ? when you turn it on or off . got a haynes manual as well but that doesnt really tell you how to fix it !!! hahahahha im a driller not a technican will inform you guys what happens tomorrow the bonnet is closed tonight ..................when i got the money im refitting with brand new wiring , !!!

[dubsweeper]

ok how do i bridge the fuel pump relay switch , finding the right switch is a battle on its own under the glove box !!

[Lima]

Assuming your fusebox is the old style one, the fuel pump relay has been highlighted with the blue line...





This is what the pins on the back of the fuel pump relay look like...





You just need to get a single wire with pins on each end similar to the ones on the relay and then plug the wire into the slots on the board that correspond with pins #30 and #87 on the pic above.

If everything is working fine, you should hear the fuel pump buzz into action as soon as you have plugged in the bridging wire (ie. you won't need to turn on the ignition).

At least, that's the procedure we followed on my car to establish that the old fuel pump relay was dead.

I have a bridging wire at home, if you're still unsure I can take a photo of it after work if you like.

[mikinoz]

Nice informative post Liam.

If you have a multimeter, you can just check the voltage across the terminals at pump when the ignition is on.

[dubsweeper]

Assuming your fusebox is the old style one, the fuel pump relay has been highlighted with the blue line...





This is what the pins on the back of the fuel pump relay look like...





You just need to get a single wire with pins on each end similar to the ones on the relay and then plug the wire into the slots on the board that correspond with pins #30 and #87 on the pic above.

If everything is working fine, you should hear the fuel pump buzz into action as soon as you have plugged in the bridging wire (ie. you won't need to turn on the ignition).

At least, that's the procedure we followed on my car to establish that the old fuel pump relay was dead.

I have a bridging wire at home, if you're still unsure I can take a photo of it after work if you like.

cool liam , just chucking out all of the amp wire and stereo crap !!!! i hate car stereos grrrrrr , the fuse box is tucked way up inside the passenger glove box and its a pain to pull out !!!!!!