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Discussion Starter #1
as title with the issue being that there is no power at the dizzy so no spark. the van used to run but had bad injectors and had done 400k so it was changed for a working engine with less miles but now has no spark.

if you use a power probe to put a live on the dizzy you get a spark and it will run. plugged in to do a diagnostic and it comes up with a immobiliser fault.

any ideas as to why or what parts i would need to change that could cause this fault or any ideas on this?

any help would be great thanks
 

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Discussion Starter #2
anyone know which wire is which on the 2.5 petrol crank sensor as some one has cut the plug off the loom and it keep throw up a fault of crank sensor low signal and crank sensor malfuction

the wires colours are black, white and brown
 

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So did you use your original wiring loom or the one that came with the new engine?

Imobiliser is in the ecu - you need the transponder box, ecu and key, they are all matched - but you should just be able to swap the engine and leave all the electrics in place.

What age is your T4? there are 3 different injection systems iirc.
 

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Discussion Starter #4
its not my van its my cousins van and i said ill have a look for him see if i can get it going or if i can find out anything on the net.

its a 51 plate 2.5 petrol. the new engine is in and the imobiliser issue is now sorted as it came with two keys and one of the keys dose not seem to have a chip with it so that was that.

the crank sensor plug was cut off the van loom (3 wires) and it looks like some has fitted a new sensor but its only a 2 pin one so they just left the thrid wire hanging around. im just looking to find out what wires do what on the loom so i can get the sensor wired back up right and see if that cears the fault.

i also take it with out this sensor plugged in it wont send power to the dizzy so you wont get a spark because the ecu dose not know where the crank is in realtion to TDC?

any help would be great on this and also ordered a new 3 pin sensor from TPS yesterday and that should be here tomorrow
 

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Right, that looks like an AVT runing Simos 3.5, from the engine table I have.

The diagram shows 'G28, Engine speed sensor' which has two wires going to it, from connector T2u/2 and T2u/1, which is listed as a 2 pin connector near starter, it is shown as having an earth shield upstream of that connector, which goes to pin 99 on the ecu.

Connections:
T2u/2 - brown - ECU pin 98
T2u/1 - white - ECU pin 106.
Sheilding - black - ECU pin 99

Are all the injectors in the old engine dead? Im after one if they match the partcode.
 

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To clarify - it looks like it should use a 2pin crank sensor - I am assuming that T2u is the crank sensor plug and it only goes 3 wires upstream of this.
 

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Discussion Starter #7
awesome thanks for that

only one of the injectors was dead so if you have a part number ill check for you as im about to go up there
 

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Discussion Starter #9
No worries mate.Do you know how many volts the dizzy should be as it's powered by the ecu. Was told it should be five volts if it's powered off the ecu or 12v if it's not

I have 5v there but still don't have a spark

Anyone have any ideas?
 
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