806 hdi wont start

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Mosser
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806 hdi wont start

Post by Mosser »

I bought a 2002 806 quicksilver hdi off ebay with what i believe to be the DW10ATED engine and the bosch ecu.

It was a non runner and had been diagnosed by the previous owners garage as needing a new ecu due to them loosing the key, the previous owners ordered the correct key with the correct immobiliser chip in it, and this key turns off the blinking immobiliser led when then ignition is switched on, so it looks to me like the immobiliser code has been accepted and is ready to start the engine, however, it just turns and turns with no starting at all, a little damp start sprayed into the intake gets the engine running until i stop spraying so it looks to me like the injectors arent firing at all.

From my research on previous posts, it seems that you need a certain pressure from the in tank pump to activate the high pressure pump, and you need a certain pressure from the high pressure pump before the ecu will give the signal to fire the injectors, and I wanted to test the pressures i am getting from the pumps to see if they were ok, I dont have any pressure gauges, but will get some if needed and if i know what type to get, the low pressure lift pump puts out enough pressure in its 3 second prime when the ignition is turned on for me to feel it pushing against my thumb when i am holding the end, but it doesnt feel particularly powerful to me, I would estimated at about 6-10 psi ?, what sort of gauge can i use to test the pressure with ?, does anyone know ?

Or, is there a diagnostic program that i can use with my computer (with a suitable interface) that will give me access to the pressure sensors for the high and low pressure fuel supplies ?

I have a VAG-COM interface from my previous seat leon that i used to play with, but this interface doesnt seem to work at all with a peugeot ?, I have succesfully used the interface with an alfa romeo 156, but the peugeot gives no response at all.

Does anyone know what the fuel pressure should be for the in tank pump, and the high presure pump ?

Is there anything else i can check that might be causing it not to start that anyone can think of ?.

I was thinking that it could be a cam position or crank position sensor fault, but i dont even know if these HDI engines use them ?, and i would still need some software or a standalone diagnostics unit that could access the systems on this car ?, and i cant find a haynes manual for it, so have no wiring diagrams or parts diagrams to work from either !, anyone know where i might get these from too ?

Sorry for all the questions, but i'm eager to get stuck in on this one and get it running, I am an electronics engineer by trade, and have changed a few engines and done heads, clutches etc so am fairly handy with the spanners and like to think i can fix anything i put my mind to, but i'm drawing blanks on finding the information i need to get stuck into this one !
2002 Peugeot 806 quicksilver HDI with bosch ecu
RichardW
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Post by RichardW »

AFAIK the low side pressure must be > 2.5 bar for the engine to start. The high side pressure is 1600 bar - I would not recommend trying to measure this! Bernie made a post in the Citroen section a couple of weeks ago about and EBOD diagnostic tool that would talk to his Xantia HDi - including live data streaming, so the same should be true of the 806. Whether you will get anything sensible out of it whilst cranking I don't know.

There are 2 well known weak points on this system - the lift pump and the fuel rail pressure sensor - either will cause a non-start situation. The main injection relay is also known to give trouble. My mate had trouble with his 306 HDi, and eventually found that the emergency fuel cut off had partially activated - worth looking to see if the 806 has this, and if it is fully pushed home.
Richard W
Mosser
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Post by Mosser »

That was a quick reply, I just took apart my tyre pressure gauge and combined with the nozzle on my compressors air gun managed to read 15psi of pressure on the fuel line comming from the tank, I realise that this isnt in any way an accurate gauge, but i really dont think i have 36psi of fuel pressure on the rail, I'm hunting for my skyes pressure gauge now to get an accurate reading on it!.

I have a fully charged battery reading 13.9 volts at the moment (fresh off an overnight charge) and I can hear the pump running in the tank, but that pressure the fuel pump isproducing is way off the mark, 2.5 bar is 36 psi, so its looking like a lift pump faliure to me now

I will be doing a hunt for Bernies post on diagnostics, as i really want to get hold of a diagnostic program for my car, and if anyone around this area wants free diagnostics, i will be able to offer it too !!
2002 Peugeot 806 quicksilver HDI with bosch ecu
504GLD
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Post by 504GLD »

The workshop manual for the 806 is a Peter Russek publication,

http://www.russek-manuals.co.uk/

your basically directed to a UK ebay shop, but the manual looks to have everything you'll need.
Mosser
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Post by Mosser »

If the russek manual covers the 2002 diesel i would snap it up !!, but sadly, as far as i can see, they only cover the petrol models up to 2001
2002 Peugeot 806 quicksilver HDI with bosch ecu
504GLD
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Post by 504GLD »

maybe its worth emailing to check, as the Amazon entry says diesel....

http://www.amazon.co.uk/Mechanic-Citroe ... 636&sr=8-1
Mosser
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Post by Mosser »

I will send them an email to see what they say

thanks
2002 Peugeot 806 quicksilver HDI with bosch ecu
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