Omega Owners Forum
Omega Help Area => Omega General Help => Topic started by: biker on 14 December 2007, 08:49:48
-
:'( Can anyone help me with a problem that has occured, my pride and joy wont start, gone through the usual checks, fues etc, but I have noticed that the fuel pump is not making any noise is there a relay or something else I need to check, I tried a direct feed wire from the batt to the pump and it works the pump, well it makes a noise in the engine bay so i presume its working, if its a relay could you point me to the right one in the fuse box.
:y thanks in antipitation, dave.. :(
-
Model? Engine? Year?
-
I see from your previous post that you have a 2.5 V6.
The fuel pump is in the fuel tank. So I don't know
what you've shorted out with your lead, or what the noise
is you are hearing in your engine bay?
The fuel pump will only run for a few seconds to prime the
fuel system for starting. It will then be signalled to run again
by the ECU when the ECU receives a valid signal from the
Crank Sensor.
Do a paperclip test and see if you have any codes.
http://www.omegaowners.com/forum/YaBB.pl?num=1189022687
-
Yup, paper clip test required....it is classic crank sensor failure.
-
OK, done the paper clip thing, reading code 31, still no wiser does some kind person have the codes to hand. :-[ had a look round to no avail....
-
OK, done the paper clip thing, reading code 31, still no wiser does some kind person have the codes to hand. :-[ had a look round to no avail....
code 31 means no rpm signal, this is normal when the engine is off.
I take it the engine cranks, and it tries to fire?
-
engine turns over but doesn't fire, took fuel lines off no fuel preasure there but it was stood over night would it make a difference to the preasure?? I have ordered new crank sensor for tomorrow hope this might be the problem, :'( :'( :'(
-
Two things to try
1) Try cranking for a few seconds with a small amount of throttle applied (to rule out an idle valve stuck shut)
2) Try swapping the two purple relays in the engine bay fuse box....they are the two closest to the screen
-
Ok done the relays already, will try the throttle thing in a mo- god its freezing
-
Does the ECU light flash?
-
It flashes the code fault is this what you mean :-/
-
I Think Mark meant, does the ECU light flash when you attempt to start, as this indicates the immobiliser is stopping you.
-
thanks for that jim, will look in the morning as i am shattered
-
ok senario is that the ecu light does not flash when turning it over?? is this indicating to the dreaded cam sensor problem then >:( :o
-
ok senario is that the ecu light does not flash when turning it over?? is this indicating to the dreaded cam sensor problem then >:( :o
Have you done the paper clip test on it yet?
-
yes and no faults shown, code 31 came up
-
Hmmm, oxygen sensor, think that's normal.
Not too familiar with 6 pots, someone will be along shortly to advise.
-
ok done all checks suggested, still no go anyone help with anything else that I am missing, PLEASE.... :(
-
any techy guys got any help on this one, desperate now, :-/
-
Hi Biker. Let's take a deep breath and start again.
You said that you ran a cable from the battery to the fuel pump,
heard a noise in the engine bay, and assumed your pump was running.
The fuel pump is mounted in the top of your fuel tank. Access is through
a circular panel in your boot floor.
Are you saying that you ran the cable all the way to the back of the car,
through the boot access panel, disconnected the pump plug, connected to
the pump +ve terminal, and rigged up a separate earth return?
If you didn't, then you haven't checked your pump is running.
You also said that you disconnected the fuel lines and there was no fuel
pressure. Seeing as you would have done this after your car failed to start,
it's a fair assumption that you exhausted any pressure and the pump
failed to run and re-pressurise your fuel system.
This means that either:
1)Your ECU is not energising the fuel relay. Either because of no signal from
your Crank Sensor, an open circuit in the relay energising circuit, or a faulty
relay.
2)A fault in the pump circuit that the relay energises. This could be the +ve
feed or the earth return.
3)A faulty pump.
4)Your fuel guage is knackered and you haven't got any fuel in the tank.
(Don't laugh. You wouldn't be the first to have this)
Do you have a multimeter or a test bulb that you can check your circuits with?
If you haven't you can't go much further until you do.
You need to check all your circuits. Remember that the relay and the pump
circuit will only work for a few seconds when you switch on the ignition to pressurise
your fuel system for starting. When you crank the engine over, the circuit
will only energise again if the ECU receives a correct signal from the Crank
Sensor.
Bearing this in mind, that you'll only have a short time window to check for a feed,
check that you're getting a feed to the pump fuse. If not you need to check the
continuity of the circuit between the fuse and the Relay. If ok, you need to check if the Relay
is operating. Check the continuity between the ECU and the Relay operating circuit.
If OK, then check out the Relay by taking it out and rigging a circuit to provide a
positive feed and Earth return to the Relay operating circuit, listen for it it click, and
check for continuity in the main circuit that it makes when it operates.
If OK, replace your Crank Sensor.
If there is a +ve supply to the pump fuse, then you have a problem with either
the circuit to the pump, that includes the +ve feed and the Earth return, or a
faulty pump. Disconnect the plug from your pump and check you are getting
12V to the pump. If not you have a wiring fault between the Fuse and the Pump.
If OK, check the continuity of your Earth return from the Pump. If faulty check
the cabling and repair the fault when found.
If everything OK, then you are looking at a faulty pump. But before condemning it,
rig up an independent +ve feed and Earth return to the Pump from a battery
and check that it actually doesn't run, just in case you've made a mistake in your
other checks. You don't want the cost of replacing a pump unless you are certain.
Post up your results as you run through the checks, or anything you are unsure of,
and electrical experts on here will give you an answer or an opinion.
Just work through everything logically, eliminating possible faults one by one.
Do NOT just go and buy a spare on spec. You'll rapidly empty your wallet to
no effect.
Good luck! :)
-
Ok, so have you tried the basic stuff? Get a screwdriver, remove number 1 HT lead, put the screwdriver in it, and the put it so that the metal part of the screwdriver is within 1/8" of the engine (inlet manifold should work).Then crank it over a couple of times. You should see a spark. If you dont, then you will be wasting your time with the fuel pump. A spark plug would be better, but its whether you have a spare knocking about...Omegas have problems with the crank sensors, it's a fact unfortunately. It isnt so much the sensor, but the fact that the wiring to it runs next to the exhaust pipe. It is easy enough to change, just dont worry about trying to use the orginal cable route, just clip it somewhere more sensible than Vx did. (although they only put it there because they built the block as a lump, complete with the electrics at the factory). You can get a sensor from Ebay for about £35. You will need an E10 torx socket to remove the old sensor, which is next to the oil filter, passenger side, by the gearbox. The plug is right at the the back of the engine, somewhere in the middle at the top .You can get to it without taking the scuttle off (I know I did, even with the LPG solenoids in the way).
-
This is excatly the problem i have with my 3.0 V6 Omega Elite, i tok it to the garage, they tested it, changed the Crank sensors, erased all faults but syill indicating no RPM signal.....The mechanics don't know what else to do, not i am taking it to another garage.
This is very annoying, nobody knows what the problem is, NO RPM SIGNAL...
-
ok guys gonna check it all again the only thing I havent done is change the CCS, I have bought a new one so I will fit it today, plus it has new Relays on for fuel pump+injectors, I love my car to bits and dont realy want to give it to the garage to fix-rip me off etc, thanks for advice yet again.. :y
-
ok guys gonna check it all again the only thing I havent done is change the CCS.......
what is CCS ? and could Fuel and injector relais be responsible?
-
ok guys gonna check it all again the only thing I havent done is change the CCS.......
what is CCS ? and could Fuel and injector relais be responsible?
Its actualy CPS...Crank Position Sensor...
If it does not detect crank rotation then it stops the injectors and spark.
-
With the info we have, I would suggest changing crank sensor is the next thing to do.
Remember - code 19, definately knackered crank sensor. Code 31 on a non running engine is non conclusive.
-
The Garage said they changed the Crankshaft Sensor and cleared all the codes but it still wouldn't start.
-
The Garage said they changed the Crankshaft Sensor and cleared all the codes but it still wouldn't start.
Can you check your receipt for a part number......and possibly have a look at the item on the car to confirm it looks new (its next to the oil filter).....I dont trust garages!
Also remember that a fault code is an indication of a problem in the circuit.....ie sensor, connector or wiring....
-
success at last CPS at fault now running like it should, sweet, thanks to all who helped with there advice, this is why forums like this are invaluable, cheers guys :y :y and merry xmas to you all..
-
success at last CPS at fault now running like it should, sweet, thanks to all who helped with there advice, this is why forums like this are invaluable, cheers guys :y :y and merry xmas to you all..
Excellent :y
-
So did the garage really fit a new sensor first time round?