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Fuel pump
Posted: Tue Jan 24, 2017 12:26 pm
by Farrierman
Should the fuel pump how power to it with the ignition on as it not making any noise and car won't start check 11 fuse which is ok . Left car running for 15 to defrost windows then died ?any help?
Re: Fuel pump
Posted: Tue Jan 24, 2017 12:38 pm
by Yeti
fuel pump only works when the car starts so you wont have a feed until you try to turn it over
Re: Fuel pump
Posted: Tue Jan 24, 2017 12:48 pm
by milescook
Make sure your pump is getting power with a 12v bulb connected to the connector. If it is getting power but still ins't pumping, especially if it's the original pump 25 years over 100k miles or so then yeah change the pump.
Re: Fuel pump
Posted: Tue Jan 24, 2017 12:48 pm
by milescook
Make sure your pump is getting power with a 12v bulb connected to the connector. If it is getting power but still ins't pumping, especially if it's the original pump 25 years over 100k miles or so then yeah change the pump.
Re: Fuel pump
Posted: Tue Jan 24, 2017 2:46 pm
by Farrierman
Think it may be the crank sensor
Re: Fuel pump
Posted: Tue Jan 24, 2017 3:42 pm
by BenHar
The fuel pump only gets power when the ECU gets a signal from the Crank Position Sensor to say that the engine is turning.
Ben
Re: Fuel pump
Posted: Wed Jan 25, 2017 4:54 pm
by Farrierman
Have checked and no sparks at all
Re: Fuel pump
Posted: Wed Jan 25, 2017 6:48 pm
by Brianmoooore
No fuel pump and no sparks when the engine is cranking is usually down to: a duff crank position sensor, a duff ECU, or one or more power feeds missing from the ECU.
Crank position sensor failure is common, but, unless it's lead has been physically disturbed, they don't usually fail totally and suddenly as you describe. Typically the car will initially start and run normally from cold, but will develop a worsening misfire as the engine warms up, only running normally after the car has cooled down. The fault typically gets progressively worse, until it totally fails, even when cold.
Failed ECUs are rare.
To check for missing supplies, first pull out the DME relay with the ignition on, and reinsert it. It should click as it is removed and as it is replaced.
Where is your battery?
Re: Fuel pump
Posted: Wed Jan 25, 2017 7:35 pm
by Farrierman
In the front
Re: Fuel pump
Posted: Wed Jan 25, 2017 7:38 pm
by Farrierman
Fuel pump is working just no sparks , was ticking over fine for 15 minutes then died thought it had run out of fuel ,turns over but didn't even try to start ...?
Re: Fuel pump
Posted: Wed Jan 25, 2017 7:39 pm
by Farrierman
Which one is dme relay ?
Re: Fuel pump
Posted: Wed Jan 25, 2017 8:49 pm
by Brianmoooore
It would help a lot if you mentioned what engine you have!
Re: Fuel pump
Posted: Wed Jan 25, 2017 10:21 pm
by Farrierman
It's a j reg 325 .with Kent cam and btb six branch ,sorry
Re: Fuel pump
Posted: Wed Jan 25, 2017 11:42 pm
by Brianmoooore
DME relay is the 5 pin one, usually white, under the cover on the LH inner wing by the airfilter, but if you now say that the fuel pump runs when the engine is cranked, that is irrelevant.
Fuel pump running and no sparks is unusual, and is most likely to be coil or distributor related.
Turn the ignition on and check for 12 volts (preferably with a 12 volt bulb) between the coil + terminal and a good body earth, and then between the coil - terminal and the body earth. Bulb should light on both.
If all is good here, pull the king lead from the coil, push the bared off end of a piece of wire into the king socket, hold the other end of the wire a mm or so away from the engine or a nut on the body with a pair of well insulated pliers, get someone to crank the engine, and see if you get sparks.
Make sure you keep the wire end close to the body while the engine is cranking, and that your pliers are well insulated, since the coil can produce around 40,000 volts open circuit, which you won't enjoy if it gets the opportunity to pass through your body!
If you do get sparks, then it's time to remove the distributor cap and check its condition inside.
Re: Fuel pump
Posted: Thu Jan 26, 2017 8:31 am
by Farrierman
Thanks great help will let you know .alex
Re: Fuel pump
Posted: Sat Jan 28, 2017 7:53 pm
by Farrierman
Changed crank sensor and coil pack still no sparks !! Maybe ecu which I have taken out to see if it is damp ? Any other ideas ? Ecu is a 0 261 200 380 .It had a new distributor cap and Rotary arm less then 2000 miles ago with top end rebuild but will check theses tomorrow ??
Re: Fuel pump
Posted: Sat Jan 28, 2017 10:21 pm
by Brianmoooore
Couldn't be the crank sensor if the fuel pump runs, as I said in my last post.
If you didn't get sparks direct from the coil king post, then there's no point in checking the distributor either.
It's important when fault finding not to mess with things that it can't be, since you run the risk of introducing extra faults that you didn't have originally.
380 ECU is known for unreliability, but for giving poor idle control, not for failing to produce sparks.
Have you checked that there's 12 volts on the coil + terminal with the ignition on? I once owned a 325i where the immobiliser had been carefully spliced into this wire, instead of the factory supplied connecting point.
Re: Fuel pump
Posted: Sun Jan 29, 2017 8:54 pm
by Farrierman
Does have a immobiliser which I hate it allows the car to turn over ,and is not factory fit
Re: Fuel pump
Posted: Sun Jan 29, 2017 8:58 pm
by Brianmoooore
Connect a piece of wire directly from the coil + terminal to the battery + pole, and try to start the car. Do not disconnect any wires.
Re: Fuel pump
Posted: Mon Jan 30, 2017 6:06 pm
by Farrierman
Tried that still nothing
Re: Fuel pump
Posted: Mon Jan 30, 2017 11:21 pm
by Brianmoooore
If everything you've said so far is correct, especially that the fuel pump kicks into life when cranking, then it's beginning to look like the ECU, unless the immobiliser is connected in a very unusual way.
The output to the coil is pin 1 of the ECU, so you could check that for continuity and for shorting to earth.
Re: Fuel pump
Posted: Sun Feb 05, 2017 8:46 am
by Farrierman
Have a new ecu will try today
Re: Fuel pump
Posted: Sun Feb 26, 2017 2:11 pm
by Farrierman
Fixed the car was the silly immobiliser playing up ( well my 68 year old dad did ) thanks for all the help had to mot tomorrow .
Re: Fuel pump
Posted: Sun Feb 26, 2017 7:12 pm
by Brianmoooore
Brianmoooore wrote:Connect a piece of wire directly from the coil + terminal to the battery + pole, and try to start the car. Do not disconnect any wires.
This would have bypassed the immobiliser, if connected like all immobilisers I've ever seen.