imobiliser

just converted my 3.5 defender into a 3.9, got everything going but the injectors wont open. found that there is a code in the key that lines up to a collar round the barrel. need to bypass this so whats the best way and what is the voltage used for the imobiliser. its on a disco about r reg

v8tricky said:

a disco about r reg

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yu dont know?

[smile] alarm bells [/smile]

it is a scrapper that has had most things removed. was only the engine i was after but it still ran in the car so he sed, was either 200quid for engine or 300 for the whole car and i could hear it running myself. have sold axels and it has got a nice leather interior to sell. didnt have number plates on it and he sed he would just send the log book off as scrapped so thats y dont exactly now wot year.

12 volts is used for all the electrical equipment on a V8 disco, when immobilised various circuits in the engine ECU are isolated, one of them is the fuel pump... so maybe injector switching is another one.

Perhaps fit a ECU from a 3.9 that was not equipped with an immobiliser ?

have narrowed it down to the injectors are imobilised, the fuel pump is working everything is working but the ecu wont open the injectors. a spark told me that the imobiliser could be 3volts 5 volts or 12 volts and if you put the wrong amount down it could blow the ecu

I don't know how the immobiliser circuit is integrated to the injection system, I thought it was separate. Anyway, injectors on 3.9 Hotwire EFI are as far as I know earth switched. There was similar thread not that long ago with the same problem, turned out to be the EFI loom. If you do a search I'm sure you'll find it. Carefully check the loom for continuity and earth. It might also be worth just making sure it isn't an ECU issue by testing by substitution.

Check and double check all the earth points, make sure they are all clean and tight.

Also, as far as I know, the 14 CUX ECU that was used for hot wire injection systems did not change from the first hot wire Range Rovers so you should be able to use any 14 CUX ECU but be aware there are at least 2 or 3 part numbers for the same box of tricks. Let us know how you get on.

Here ya go, have a read of this

http://www.landyzone.co.uk/lz/f42/looming-problem-96472.html

It may well be that you need to modify the loom. Knew I'd seen something like this somewhere!

Theer is another thread but I haven't found it yet.

ive found the wire that goes into the ecu to corrispond with the imobiliser, ive also got a complete pin code data sheet that lists each wire and numbers them. it also tells you what voltage they are but this is the only one that isnt listed and i dont know how to bypass it cos it could blow the ecu if i just connect it to the ignition live
also, wots the diff between a hot wire and a paddle engine?

v8tricky said:

ive found the wire that goes into the ecu to corrispond with the imobiliser, ive also got a complete pin code data sheet that lists each wire and numbers them. it also tells you what voltage they are but this is the only one that isnt listed and i dont know how to bypass it cos it could blow the ecu if i just connect it to the ignition live
also, wots the diff between a hot wire and a paddle engine?

Click to expand...

Have read of this thread:

http://www.landyzone.co.uk/lz/f42/3-9-v8-efi-auto-into-90-defender-102543.html?highlight=efi+loom

and I guess you mean the difference between hotwire and flapper? Well essentially they are quite similar but flapper has a flap air flow meter and is a Bosche injection system. Hotwire is a modified Bosche system by Lucas (Lord of Darkness) with a slightly more sophisticated ECU.

If you're using a Disco loom, then I suspect you have a spider related problem.

im in the know about the hot wire etc now cheers. wots a spider app from the obvious. i am using the loom from the same disco the engine came out of. just pulled everything through the bulk head and the spliced my loom into the discos. have got power to the injectors when ignition is on but they just wont pulse. a spark has just rung me back and he is going to have a look tomoz

Hold up. Here is another thread you should take a quick look at.

http://www.landyzone.co.uk/lz/f42/help-3-9-efi-not-starting-108872.html?highlight=3.9

Have you actually done a search?

my mate who owns a garage who helped me drop the lump in looked on the web and his data base an wreckons he couldnt find any decent diagrams etc. 4 people have cast their eye over it and have all come to the same conclusion that its got to be be just litterally a wire that needs to have a feed to it. the mechanic next door sed initially the other day that the discos factory imm stops the injectors from fireing. i hate wiring stuff not my forte thats why im just going to turn it over to the spark and let him do his stuff. cheers for your input and if this bloke cant get it running then ill come back to you and run through everthing you have said, but have done lots of checks and it all seems to work as it should:fighting: this mite be the alternative

i would gues at the spider not connected or the bypass plug has not been fitted