Dieseling after shutoff

[Mykul01]

So I finisqhed my AEB swap in my mk1 cabriolet! I'm using an ABA alternator with the two prong plug iGnitor wire. http://http://farm4.static.flickr.com/3124/2778679025_5661ab1206.jpg
Or this one the plug is at the top of the photo and is a two prong square plug
http://http://farm6.static.flickr.co...557ef58ab5.jpg

So here's what happens. With the alt mounted to the bracket in the car, the prong towards the front of the car is the one that is the iGnitor wire! the other prong on the two prong plug blows the fuse immediately. The prong or terminal towards the front of the car (this is on the two prong plug mentioned above on the alt) is the ignitor wire that doesn't blow the fuse and the alt starts charging the system as the battery immediately now read 14.7 volts. The fuse also doesn't blow! But now when I try to turn the car off it does a "dieseling" such as a sputter that pewters out to eventually shutting the engine off?? I ran the wire I'm using for the alt ignitor myself, by using an auxiliary fuse block I installed to wire the AEB engine up in The car! My point being I'm not using the original ignitor wiring. So I can't be back feeding??? Right??? Any ideas why it would be doing this???? Thanks

[MikkiJayne]

Where did you run the wire to, and why aren't you using the original wiring?

[Mykul01]

Where did you run the wire to, and why aren't you using the original wiring?

The wire is ran from a 12V ignition on the auxiliary fuse block to the forward most terminal on the two prong alternator plug! I'm not usinug the original wiring because much of the original engine harness was cut out when the old engine was removed! To clean up the engine bay. Unfortunately I over looked the need for this wire and deleted it

[MikkiJayne]

Ah thats your problem then. The alternator field / ignitor wire has to run through a bulb / LED / the cluster to work properly. The bulb is connected to ignition on one terminal (normally inside the cluster) and the alternator on the other terminal.

What happens is when you turn the ignition on the field wire is grounded (inside the alternator), so the bulb lights up. When you start the engine and the alternator spins the 12v coming though the bulb allows the alternator to start making current. It feeds the current back up the field wire so your bulb effectively has 12V on both terminals and goes out.

As you don't have a bulb in the circuit the alternator is trying to feed back in to itself. Its trying to make the car run through the field terminal, but can't supply enough current so it coughs and splutters as the voltage drops until eventually there's not enough left to run the ECU and it dies.

If you connect your wire up to the alternator light terminal on the cluster it should work just fine. If you don't even have that any more then you could just use an LED or a small bulb (like a side marker or interior light bulb).

Hth

[Mykul01]

Ok wow that is awesome. I'll try find the wire I cut but may be quit hard??? If not I can just run a bulb in series with the ignitor wire before it reaches the alternator an it should work?? That will be the easiest way to go for sure. Thanks so much for the reply MikkiJayne

[Mykul01]

Ok wow that is awesome. I'll try find the wire I cut but may be quit hard??? If not I can just run a bulb in series with the ignitor wire before it reaches the alternator an it should work?? That will be the easiest way to go for sure. Thanks so much for the reply MikkiJayne

Ok after reading it again just a bulb in series won't work! I will work on finding the original ignitor wire! Anyone know wher it comes thru the fire wall on a 85 cabriolet? Thanks

[MikkiJayne]

Yeah a bulb will work Put it between the switched ignition and the ignitor wire.

The original wire ought to be on the cluster connector though, assuming the cluster is still there? Connect the wire you've already run to the switched ignition to the that terminal on the cluster connector instead and you should be good

[Mykul01]

You were so right. I put a bulb in the ignitor line and works PERFECT!!!!!!!! This will buy me some time till I take the cluster out again. I have to move some gauges. Thanks so much the bulb works awsome.