Help Dead Engine
Discussion
coming back from le mans after a fantastic week of driving
the car cut out on the roundabout,
pulled over started to check things out and the fuel pump wasn't priming (this was a new one),put a live feed to fuel pump and it ran.
check fuses the 25 amp ignition fuse had blown put another one in blew again
tried a stronger one blew again ,
anyone one know what the problem could be ,
also looking at wiring diagram
it goes to the pink engine run sensor (what is this) is it the same as the fuel pump relay ,also could a fuel pump relay fault cause the fuse to blow ,had to suffer the embarrasment of being towed back (mind you saved me a fortune in petrol)
felt a bit beter when there were 2 ferraris on the same breakdown truck
the car cut out on the roundabout,
pulled over started to check things out and the fuel pump wasn't priming (this was a new one),put a live feed to fuel pump and it ran.
check fuses the 25 amp ignition fuse had blown put another one in blew again
tried a stronger one blew again ,
anyone one know what the problem could be ,
also looking at wiring diagram
it goes to the pink engine run sensor (what is this) is it the same as the fuel pump relay ,also could a fuel pump relay fault cause the fuse to blow ,had to suffer the embarrasment of being towed back (mind you saved me a fortune in petrol)
felt a bit beter when there were 2 ferraris on the same breakdown truck 
I don't see how the relay could have caused an ignition fault, unless the thing has completely melted internally. The relays are only ca. £12, I replaced mine not long ago. There are two possible relays that can blow, but both are the same part so you can interchange them and see.
Will the pump run on a fused feed, 15A should be sufficient. If that blows it may tell you that the pump is drawing too much juice and may be on the way out. If that is the case it may be worth a change in filter just to make sure that you don't have a blockage in the pipe.
Otherwise it's out with the multimeter and check the wiring.
Hope that helps,
Z
Will the pump run on a fused feed, 15A should be sufficient. If that blows it may tell you that the pump is drawing too much juice and may be on the way out. If that is the case it may be worth a change in filter just to make sure that you don't have a blockage in the pipe.
Otherwise it's out with the multimeter and check the wiring.
Hope that helps,
Z
Sounds like a wiring short or a fused component, but you already knew that! Blowing fuses can get tedious so while you're tracking the problem down you might want to fit a large test bulb across the fuse holder rather than a fuse? Normally it should glow dimly, if it comes on brightly you have a full 12V across it which implies a short. Alternatively you can get a resetable circuit breaker with a blade fuse form factor for a few quid. The other approach is to check for wiring damage in the feed to all the ignition switched components (instruments, coil, fuel pump, ECU etc), if in doubt disconnect them and see if you can make the problem go away. Unfortunately this could be quite a long job though!
The 'Pink engine run sensor' is the fuel pump relay (but its not just a relay - there are ignition pulse detector and timer circuits inside too)
If you managed to run power to the fuel pump and it worked then its either the relay or the wiring. Does it still blow fuses if you remove the fuel pump relay?
And does it blow fuses with the ignition on, or when you try and start the engine?
If you managed to run power to the fuel pump and it worked then its either the relay or the wiring. Does it still blow fuses if you remove the fuel pump relay?
And does it blow fuses with the ignition on, or when you try and start the engine?
Le TVR said:
The 'Pink engine run sensor' is the fuel pump relay (but its not just a relay - there are ignition pulse detector and timer circuits inside too)
If you managed to run power to the fuel pump and it worked then its either the relay or the wiring. Does it still blow fuses if you remove the fuel pump relay?
And does it blow fuses with the ignition on, or when you try and start the engine?
it blew the fuse when you start the engine , i will try and remove the sensor and see if the fuse remains intact
this was my first time in france and ther roads were excellent
with plenty of opportunity to test the car to its full potential
>> Edited by spivvy on Tuesday 15th June 16:28
my s1 did this.feed wires in the n/s engine bay had melted against the exhaust manifold causing short & blowing fuse. a short length of insulting tape did the trick 
{Also had similar prob in 2.8 capri when supply to the pump shorted after mechanical abrasion wore the insulation exposing the wires. similar solution.
less likely in the tiv as the wires are not routed close to anything.}
{Also had similar prob in 2.8 capri when supply to the pump shorted after mechanical abrasion wore the insulation exposing the wires. similar solution.
less likely in the tiv as the wires are not routed close to anything.}
spivvy said:
it blew the fuse when you start the engine
This sounds odd.
When you ran the power feed to the fuel pump and it worked did you disconnect the original wiring from pump?
If so then the wiring loom (black/yellow) is shorting. (note that fuel pump relay also powers the additional air device and warmup too. these cables sometimes run a little too close to rather hot bits....)
Good luck
Le TVR said:
it blew the fuse when you start the engine
This sounds odd.
When you ran the power feed to the fuel pump and it worked did you disconnect the original wiring from pump?
If so then the wiring loom (black/yellow) is shorting. (note that fuel pump relay also powers the additional air device and warmup too. these cables sometimes run a little too close to rather hot bits....)
Good luck
i ran the power feed to the pump and the pump worked in that is was pumping, so the fault wasn't there , with this connected and the fuse replaced it would still blow the fuse ,so it lucks like a cable short this looks like it could be a long one to fix
if i find it i will let you know
Le TVR said:
Well if you ran power to the pump (and it worked) without disconnecting the original wiring..... 
Dont suppose you have another fuel pump relay to try???
am trying to get another fuel pump relay ,
i disconnected the original live feed to the pump and ran a wire straight from the battery
and left the earth in place to existing wiring, so this i think proves there is a fault with the live feed i just have to trace back through each component and see where the fault origintes now
spivvy said:
i disconnected the original live feed to the pump and ran a wire straight from the battery
and left the earth in place to existing wiring, so this i think proves there is a fault with the live feed i just have to trace back through each component and see where the fault origintes now
Yes its the wiring then, probably not the relay.
Easiest search is with a 12v bulb connected to some long wires.
Switch everything off and connect the bulb's wires to the battery positive and the live feed to the pump.
It will probably light up showing that the loom is shorting somewhere.
Now as you move the wiring loom, connectors etc the bulb will go out when you find the short....
Le TVR said:
i disconnected the original live feed to the pump and ran a wire straight from the battery
and left the earth in place to existing wiring, so this i think proves there is a fault with the live feed i just have to trace back through each component and see where the fault origintes now
Yes its the wiring then, probably not the relay.
Easiest search is with a 12v bulb connected to some long wires.
Switch everything off and connect the bulb's wires to the battery positive and the live feed to the pump.
It will probably light up showing that the loom is shorting somewhere.
Now as you move the wiring loom, connectors etc the bulb will go out when you find the short....
thanks for that, i am off tonight to try this and see if i can find the fault
well the car is now working again
the annoying thing is i don't know exactly where the fault was. ( i did find a frayed wire in one of the looms that had caught the exhaust manifold,so i hope that was it )edited YES IT WAS THIS WIRE AS WE SHORTED IT OUT AND IT BLEW THE SAME FUSE
i now have the clutch master cylinder off as i have nice line of fluid running down the inside (still it did get to le mans and did a lot of miles whilst there so i probably wore it out)
mr plod
was not always around and with a tuscan, a gaggle of griff's tow i couldn't let the side down
>> Edited by spivvy on Sunday 20th June 20:29
>> Edited by spivvy on Sunday 20th June 20:30
the annoying thing is i don't know exactly where the fault was. ( i did find a frayed wire in one of the looms that had caught the exhaust manifold,so i hope that was it )edited YES IT WAS THIS WIRE AS WE SHORTED IT OUT AND IT BLEW THE SAME FUSE
i now have the clutch master cylinder off as i have nice line of fluid running down the inside (still it did get to le mans and did a lot of miles whilst there so i probably wore it out)
mr plod
was not always around and with a tuscan, a gaggle of griff's tow i couldn't let the side down >> Edited by spivvy on Sunday 20th June 20:29
>> Edited by spivvy on Sunday 20th June 20:30
Ali B said:
my s1 did this.feed wires in the n/s engine bay had melted against the exhaust manifold causing short & blowing fuse. a short length of insulting tape did the trick
[muttleyvoice] medal? [/muttleyvoice]
if only everything was this easy
>> Edited by Ali B on Friday 25th June 09:18
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