Rory Blackman

Hi I have a N reg 1996 1.6 16v zetec escort. the car seems to run fine and starts on the button. When I bought the car there was a receipt for a new fuel pump that was fitted and some other stuff. I noticed after a short while that that was a rattle noise that comes from the fuel tank now and then too. Anyway, if I drive for 10 mins plus and stop the car completely it will not start again. Some times nothing at all some times it idles chutters and stops. after waiting the car will start fine and I have noticed you can here the fuel pump prime when it is going to start again. Some times it will be 5-10 mins even after a really long drive other times an hour plus but if left over night it will always start. It has never not started from cold.

So I have checked the fuel cut off switch in the foot well and that is not being tripped. I seems strange because it only does it after it has been driven for some time.

There is no access panel under the seat so it's no small job to change. Any ideas before I drop the tank out? Might it be a sensor, loose conection/fuse/diode or ecu issue. A new pump is £200 or a second hand take it off your self is £15 but it's still time and effort if it does not solve the issue.

Any help would be great.

Brendan

iTrader: (1)

have you got a DVM and a current meter?

http://www.maplin.co.uk/domestic-multimeter-37279
http://www.maplin.co.uk/automotive-c...-tester-217879

you need to check volts and current at the fuse to see if it is the pump or electrics!

Rory Blackman

I have a multi meter but not the other one. for £13 it maybe worth purchasing tho. what fuse do i need to measure across?

Many many thanks.

Rory Blackman

EDIT so the car is not running and the pump not priming. If the key is turned to 3 then the car will crank but not start.

I have checked the fuel cut off switch (the one in the drivers foot well) there is 12 volts across this when the key is turned and I bridged the connector to test that the switch was not to blame.

Next:
Under the back seat i stripped back the wires a little and checked the voltages across them all. nothing with key not turned but with the key at 3 and 2 there is 5 volts between any of the black wires and the white one, and the white wire and the top of the tank. I then tripped the fuel pump cutoff switch and repeated the same test getting the same results. My guess would be that this 5 volts is flowing from ground to white wire in fact.

with the pump not priming I am waiting hoping for what every resets to do it's thing and then test the same things with the car going.

Rory Blackman

p.s would the crank sensor cause this intermittent problem?

vaughant

iTrader: (1)

You should be recieving the full 12v at the pump IMO.
Could you get a wiring diagram up from Haynes etc and I can tell you then the exact points that you should be testing to see what voltage your getting etc.
My guess is poor wiring or a bad fuel pump relay contact.
Also fuse boxes are well known for failing on these and that could be where your 7 volts are dissapearing to.
Crank sensor shouldn't affect the voltage at the pump.
I had a mk5 can years ago and it was just poor connections on the pump/sender unit on top of the tank.

Rory Blackman

So it wouldn't go almost allday and then I shut the back door (been open to get at the pump) noticed the child lock lever sticking out so flip it as that back door locks funny on the central locking sometimes. Locked and unlocked the car and she went fine.Last time it stopped for a long time I called out the AA and it went that time just before they got there after locking and unlocking the car. I also checked the voltage and had 12 volts at the fuel pump as you would expect.

Where is the relay ? I looked but couldn't find it. I'm thinking of changing it to rule it out.
The lock on the drivers door plays around sometimes, Is there anychance this is an immobiliser issue? Aloose connection on the door lock?

However after running the car and then turning off and not getting out or even touching the doors it will do the same thing.

This is a 500 quid car at the end of the day but is in really nice nick apart from this odd issue.

Anymore help would be great.