What Have I Done Wrong?

[kate205gti 4]

still having fuel pump issues - going to pull my hair out soon! I've managed to hardwire the fuel pump into a switch on the dash so the car would run, but this was a permanent live so figured mr MOT man might not like this, so tonight i wired it into a switch on an ignition live instead

 

switch turned on, keys out - no fuel pump priming, keys in and switched to position 2 - fuel pumps primes, turn key off and fuel pump stops again - lovely so figured i could leave the switch in the ON position and just use the key to start and mr MOT man wouldnt know any different

 

however once the car is running i can now turn the keys to off, take them out the ignition and wander off and make a cup of tea and the cars still running yet if i switch the switch off to stop it then on again the fuel pump doesnt prime until i put the keys back in and turn to position 2

 

how is this possible? and how can i stop it running on on its own accord please?

 

 

also how do you hardwire fan switches? I tried putting a live feed in the back of the white flat connector (the right side too - not the earth - i double checked!) and it just sparked and made a funny smell

[jakey 1]

Feel free to come have a look at how my mate has wired my fan and fuel pump in, if you wish?

 

And where was my call? Need to sort indicators!! lol

[kate205gti 4]

i called u but you were engaged i have the patience of a gnat (and was upside down in the footwell) sowee

 

bring your car to the barn u can look at my indicators while i look at your fuel pump wiring lol

[hothatch 2]

still having fuel pump issues - going to pull my hair out soon! I've managed to hardwire the fuel pump into a switch on the dash so the car would run, but this was a permanent live so figured mr MOT man might not like this, so tonight i wired it into a switch on an ignition live instead

 

switch turned on, keys out - no fuel pump priming, keys in and switched to position 2 - fuel pumps primes, turn key off and fuel pump stops again - lovely so figured i could leave the switch in the ON position and just use the key to start and mr MOT man wouldnt know any different

 

however once the car is running i can now turn the keys to off, take them out the ignition and wander off and make a cup of tea and the cars still running yet if i switch the switch off to stop it then on again the fuel pump doesnt prime until i put the keys back in and turn to position 2

 

how is this possible? and how can i stop it running on on its own accord please?

 

 

also how do you hardwire fan switches? I tried putting a live feed in the back of the white flat connector (the right side too - not the earth - i double checked!) and it just sparked and made a funny smell

 

first of all what is the reason you hardwired the pump in ?

 

To wire the fan to a switch you should use a relay. 4 connecters on the relay, one you want to earth, another is a small ignition live feed, another is a bigger live out to the fan and the other is for your switch. Put a fuse in both the switch circuit and the live to fan feed.

 

Any help for you?

 

Edit ! Sorry! 1- earth 2- ignition live 3- live from battery 4- live to fan with swith in circuit .

Edited May 12, 2010 by hothatch

[fatony1 17]

Sorry i can't help with the problem but i assume this is the engine i sold you? Glad everythings OK with it

[dcc 855]

a case of "ill show you mine if you show me yours?"

[jakey 1]

I can't bring it to the barn, not on the road yet!! :s

 

And ok sorry, you are forgiven!

[dcc 855]

is it possible you have taken a live which is only live when the circuit is completed by the alternator. i dont quite know how to explain it better than that, but in my head i kinda know what you are trying to explain.

[kate205gti 4]

hmm.. a friend has just suggested i may have wired up the coil/engine loom to a permanent live not a switched live - which is perfectly feasible lol

 

"uve got ur engine/coil/ecu connected to a permenant live rather than a switched live, so its powered up all the time. Is why it only tunrs off when u turn the fuel pump off, not when u turn the key off"

 

the engine loom wire is wire number 2a to the coil, etc.. and ive put the live from fuseboard position E2 into it - wire number 2

 

http://forum.205gtidrivers.com/index.php?a...ost&id=3333

 

but i cant find a wire number 2a in my fuseboard where else do i get a switched live from if wire number 2 is permanent live?

[dcc 855]

think the 12v lighter socket should be switched.

[DamirGTI 344]

but i cant find a wire number 2a in my fuseboard

 

It's on the E slot of the fuse box it's 2pin slot there , and this the wire No.2 should be first one from the right (was kinda strange light green or cream color wire if i remember ..) ... and from the fuse box , this one goes on to the coil .. it's switched live/positive wire via ing. barrel ..

 

Damir

 

.. and , it should be white 2 pin plug connector on the end of this the wire No.2 on the engine bay side (if the OE loom is intact .. without chopped wires/connectors ..) , cos it spreads on two sides from there above the coil - one side on to the coil positive , another side on to the ignition amp connector (positive as well of course ..) ..

 

.. and , next to it (the wire No.2) it's red one No.32a , so just this two wires on one the E slot of the fusebox , this the red one should be prime signal for the tachy relay , cos it goes via ing. barrel as well , and it's cross connected in the same circuit with the wire No.2 inside the fuse box - get the multimeter out set it for continuity testing and poke both of this wires from one to another end (from the fuse box side till the connectors in the engine bay ) ..

Edited May 13, 2010 by DamirGTI

[Anthony 1,003]

Depending on exactly how you've wired it in, my guess would be that you've got the fuel pump wired into both the ignition (via the switch) and the tachymetric relay (as standard).

 

As standard, with the engine running the tachymetric relay supplies power to the fuel pump and with the engine stopped, it cuts the power.

 

As you've wired it, the fuel pump is powered from the ignition circuit, via a switch.

 

What I believe is probably happening in your case is that the tachymetric relay is still wired to the fuel pump and powering it with the engine running, and is back feeding the ignition circuit via your newly installed switch - thus when you switch the ignition off, the ignition circuit is still receiving power from the tachymetric relay, and the engine keeps running

 

An easy test would be to start the engine, and switch off the fuel pump switch - if it carries on running, then the tachymetric relay is powering the fuel pump.

[kate205gti 4]

It's on the E slot of the fuse box it's 2pin slot there , and this the wire No.2 should be first one from the right (was kinda strange light green or cream color wire if i remember ..) ... and from the fuse box , this one goes on to the coil .. it's switched live/positive wire via ing. barrel ..

 

Damir

 

.. and , it should be white 2 pin plug connector on the end of this the wire No.2 on the engine bay side (if the OE loom is intact .. without chopped wires/connectors ..) , cos it spreads on two sides from there above the coil - one side on to the coil positive , another side on to the ignition amp connector (positive as well of course ..) ..

 

.. and , next to it (the wire No.2) it's red one No.32a , so just this two wires on one the E slot of the fusebox , this the red one should be prime signal for the tachy relay , cos it goes via ing. barrel as well , and it's cross connected in the same circuit with the wire No.2 inside the fuse box - get the multimeter out set it for continuity testing and poke both of this wires from one to another end (from the fuse box side till the connectors in the engine bay ) ..

 

ok now im confused lol (please bear with me) the E slot of my fuseboard is a 3 pin slot, from 1-3 (right to left) is:

1 = green #57

2 = red #2

3 = red #32B

 

ive labelled #57 as Tachymetric relay and #2 as Ignition module, ignition coil, diagnostic socket - not sure what 32B does? i will learn how to use a mutlimeter and see what ones join up!

 

ah that makes sens anthony - does the tachy relay do anything apart from power the fuel pump? so i can either unplug the relay or switch the fuel pump switch off as soon as its started - although might be a bit of a pain if it stalls :s

[Anthony 1,003]

ah that makes sens anthony - does the tachy relay do anything apart from power the fuel pump? so i can either unplug the relay or switch the fuel pump switch off as soon as its started - although might be a bit of a pain if it stalls :s

It also provides power for the fuel injectors, so you'll need to leave it in place.

 

Given that the relay appears to work, will the engine not start and run without the switch in place? Many 205's don't prime the pump when you switch the ignition on, but the pump should turn on when cranking and then continue to run so long as the engine is running.

 

Personally, I'd fix whatever the underlying cause is, rather than cover up the symptoms with an ignition-fed switch.

[kate205gti 4]

least i know the tachy relay works then! i'll try cranking with with the switch off and see if it fires, but i was under the impression u had to hear the pump prime before it would run - if it primes on cranking then i'll be happy if not id love to fix the underlying cause but ive been trying for 2 weeks and no luck so far!

cheers

[welshpug 1,666]

as Anthony said, they don't always prime, as long as you get power under cranking all it well, which it sounds like it isnt far off if the injectors are powered up.

[BusEngineer 7]

In the three years i ran mine every day it primed every time i switched on the ignition, i then took it off the road for 12months. Then last month i replaced the fuel pipes front to back and now it doesnt prime before starting but never struggles to start!

 

I would guess i was losing pressure somewhere in the system between tank and fuel rail and the new pipework has cured it