View Full Version : no power to fuel pump
right, got engine back in and all piped up but found theres no power to fuel pump, traced it back to fuel pump relay and found 12v at perm live, acc live and live from aei, but nothing from live out to pump,
is this dodgy relay, or should i be looking elsewere first:scratch:
thanks
New poster! (less than 10 posts)
right, got engine back in and all piped up but found theres no power to fuel pump, traced it back to fuel pump relay and found 12v at perm live, acc live and live from aei, but nothing from live out to pump,
is this dodgy relay, or should i be looking elsewere first:scratch:
thanks
has the relay got a decent earth? have you tried removing the relay and power the coil to see if the relay clicks over? if you have a multimeter you could try the resistance on the coil side of the relay and what continuity you have on the switchable side with power applied to the coil?
Bridge the red and white wires on the relay and see if the pump starts, to eliminate relay
thanks for the replys,
pretty sure its relay, if i link red and white pump does start,
any idea were i put power to check if relay clicks?
would that be live to the brown and earth the black?
ta!
Are you getting spark?? Could be the pick up.
presume im getting a spark?
But that wouldnt have any effect on the power to the fuel pump would it? :confused:
Tony Walker
03-03-2013, 14:38
yeah its an indicator of the crankshaft sensor not picking up a signal, so tachiometric relay for fuel pump wont be operated. its so the pump only runs when the engine is turning, so it doesnt pump fuel on you when you crash or should i say if you crash lol
oh..........:ashamed:
so your saying fuel pump only kicks in when the engine is turning over?
i thought it ran when ignition was on......that may be the problem then............
well it has been nearly 3 years since i last started it up!
Pump only pumps when engine is cranking. Unless you bridge the relay.....as mentioned it will either be the tdc sensor or the fpr..check for a spark to eliminate the tdc sensor
It doesn't prime when ignition is on, only when it's cranking will it run the pump (can hear it running on for a few seconds when you kill ignition though).
It still may be the fuel pump relay though as its fairly common fault but easy to check and dismiss timing sensor by checking for spark 1st.
very nearly bought a relay then!
there might not even be anything wrong with it then, seen as i was looking for power with just ignition on:ashamed:
ill just give it a good ol cranking and see if it spits any fuel out first then!!
opened up a whole new can of worms now :eek:
tried cranking it for a bit and theres no power to pump
tried to see if theres a spark, and no spark
but after messing about a bit i found power to aei goes dead while cranking:confused:
batterys died, so thats it for today.......:(
Markey Mark (BD)
03-03-2013, 16:46
Maybe the relay for the AEI unit is playing up, try replacing it or bridging it out to see if you get spark and fuel back
Also make sure the aei has a good earth as that can give you duff information aswell
Most likely the pick up then, test for resistance across the connector going to the sensor. Can't remember spec but its in the Haynes.
Try a known good relay (rad fan / lights) on the AEI too, just to be sure.
Maybe the relay for the AEI unit is playing up, try replacing it or bridging it out to see if you get spark and fuel back
My money is on what this man says don't know if this link works but Chris had the same symptoms and it cured his problem have a quick read
All the best Phil
http://www.rtoc.org/boards/showthread.php?t=31898
It does sound like it phil i did what you said and its been perfect since :agree:
just sounds like porblem chris had,
i did try a different aei relay and nothing, but so did chris!
Will try linking that out tomorrow and see what happens,
thanks again for the replys:)
still farting about with this and still no joy:cry:
so, i recharged my battery, got a new tdc sensor, and fitted it today and still no spark or fuel pump, checked wiring and i have 12v to aei, dropping to around 8 to 9v while cranking but no spark and no pump action, although on a few occasions the pump has given a little whirr when i stopped cranking, i put fuel line into a empty tub so can see if anything happens, ie any dribbles while cranking....
i have tried linking the aei relay out and nothing, and have tried 3 different aei's and still nothing, 2 different king leads....
could the knock sensor have anything to do with it?
and should i be seeing any power on the tacho wire to fuel pump relay while cranking? as there is no power there
confused.com :scratch:
on a final off topic note, thinking of getting a bosch s5 battery as i have killed my "value power" corsa battery now! are they a bit ott for a 5?
Have you got power at aei mate and at fuel pump
power at aei, none at pump
Tony Walker
10-03-2013, 21:06
if its got power then power drops off sounds like a dodgy earth... not that clued up on the 5s wiring as ive never had to repair any lol. but theres alot of earths in the passenger footwell? also i presume the relay for the aei earths somewhere around the scuttle if not directly to the battery? my wirings far from OE lol.
all earths are ok afaik, but will try running a earth from battery to aei for good measure
1 other thing,on 1 of the aei's i fitted, then everytime i turned the key it just clicked and everything went dead, lights on dash, interior light, everything off, turn it off and on again and lights back on??
knakked aei?
arnt 5's fun! :wasntme:
And do you have a perminant live at the realay by aei
And you put a wire on the perminant live to the wire to the aei
Un plug the connector of death clean all the brass terminals with a needle file Or a thin flat head screw driver then re connect and have another go the connector block is the white box by the passenger headlight under the water bottle mate
Have you touched any wires running to the starter motor at all mate ?
i linked out relay ,there is live to aei while cranking (with or without relay) but it drops from 12v to between 8 - 9v while cranking
what i dont know is if there is supposed to be voltage coming out of aei on tacho wire to fuel pump (brown wire)
and could knock sensor cause this prob?
Un plug the connector of death clean all the brass terminals with a needle file Or a thin flat head screw driver then re connect and have another go the connector block is the white box by the passenger headlight under the water bottle mate
Have you touched any wires running to the starter motor at all mate ?
ive messed with all these wires... just swapped engine:crap:
connector of death seems ok but a good clean wouldnt go a miss, and indeed starter motor wires , but i did give these a good clean first
Have you checked theres an earth on the aei
So do you still have no spark at all after taking the relay out by the aei and bridging the yellow live feed wire also do you have an immobiliser on the car or removed one
yes there is, its fastened onto the scuttle
So do you still have no spark at all after taking the relay out by the aei and bridging the yellow live feed wire also do you have an immobiliser on the car or removed one
no theres no spark after bridging, nor does fuel pump run, but do get the odd whirr ocassionaly when i stop cranking
there is an immobiliser, havent touched it, and that seems to work ok, when its armed car wont turn over,
only wiring i have touched is engine loom, swapped that with engine (good used one)
Have you definatly put the earth back on engine block and how many wires have you got to each terminal on battrey
carnt help with any of your problems mate but I have a bosch s3 battery and it has never let me down yet so maybe the s5 is a little ott but im pretty sure they come with a good garuntee. spose just depends on price difference. I wouldnt buy from halfords either much more expensive than motor factors I got mine from gsf for a good price
not sure how many wires are going to battrey terminals, there covered in conduit, but these havent been changed since it was last running
from memory i think i connected 3 earths from engine, 1 to subframe, 1 near brake servo, and i think 1 that goes to battery neutral, does this sound right:confused:
carnt help with any of your problems mate but I have a bosch s3 battery and it has never let me down yet so maybe the s5 is a little ott but im pretty sure they come with a good garuntee. spose just depends on price difference. I wouldnt buy from halfords either much more expensive than motor factors I got mine from gsf for a good price
the s4 is 45ah and is about £50
the s5 is 52ah and is about £65, worth the extra £15, or is it pointless?
Did you check the block was clean where the earth bolts too and then clean where it goes onto bulkhead clean it with a file so its shiny metal buddy. And the earths are one from block to bulkhead and then battrey to bulkhead well they are on mine
think i remember cleaning them:scared:
will check it all tomorrow, and see if a new battery makes any difference cos its knakked anyway
I painted my engine block and refitted and it wouldnt start forgot to clean earth point :laugh:
picked a new battery today, but im fekked if im going out to fit in this weather:wasntme:
the batteries are good mate im not entirley sure about the different starting power but my s3 has always been adequate so i would of thought that anything above should be more than enough
right, put new battery on today, cleaned up connector of doom, removed all earths and cleaned up, and now have a spark:D
still nothing from the fuel pump so reckon that must be relay, but have linked it out for the moment,
so, now have a new problem........ started of with fuel pipe to carb in a plastic bottle to check it and flush any crap out of lines and its fine, plenty pressure, but when i put it on carb i dont seem to get anything, took lobster off and with WOT i can just see a drip dropping off butterfly and thats it
i know carb is good, bought engine and carb off a local member a few weeks ago and saw it running before it was removed, fpr possibly??
anybody local fancy being hansomely rewarded with beer tokens in exchange for some expertise next weekend??, really getting on my tits now!!:sad:
If you have fuel going to the carb - Needle jet might be stuck, acc jet and various other jets may need cleaning.
Tony Walker
17-03-2013, 19:34
drip with ignition on or while cranking?
drip with ignition on or while cranking?
both... kind of... got fuel pump relay bypassed at moment as relays dodgy, so pump is running when when ignitions on
but tried it cranking, or just with just pump running
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