I'm at a loss

[Outlaw]

Okay as some know... i've been having problems with my disco.

Originally i started getting a sort of miss while driving untill it finally died and wouldn't start again and was put down to the airflow meter... so i had it replaced... when i picked it up and drove for 40mins home was having the same missing feel to it so put it down to being overdue for a service so figured would get it done when back from holidays.

A couple days later died again and worked out it was the fuel pump... a couple sharp knocks and it started again so had the pump replaced yesterday... tonight it stopped again and seems to be the pump again....

SOOOOOOOOOOOOO... what next??? I assume can't be the pump if just been replaced... and worst of all... does that mean the airflow wasn't at fault again at 1700 for a replacement???

I'm lost now :mad: Please Help Me :(:(:(

[DRanged]

Josh do you have constant 12V power to the pump????

If so are you sucking rubbish into the pump???

Did you check out the old pump before tossing it.???

I assume your hitting the pump because its stalling or seizing???

Just some ideas

Justin

[Blknight.aus]

what was in the fuel filter?

your fuel pressure regulator may be sticking open..

elec connection to the fuel pump... replacing the fuel pump wont fix it if its just getting an intermettant connection somewhere.

how is the fuel filter and all the subsequent fuel lines?

[incisor]

bloody useless v8's hey pedro :P

ignition module been checked?

[Outlaw]

Haven't checked anything else as yet and no haven't got the other pump as had a workshop do it for me but going to call them in the morning to see if they still have it.

Will try to check the other things tomorrow... anything else?

[LandyAndy]

Try pinching off the return line to the tank,will indicate if the fuel pressure reg is letting all the pressure back to the tank and not the injectors.
The trusty multigrips got me home one night in our XE EFI Falcoon we once owned!!!
Andrew

[DEFENDERZOOK]

i had a similar problem on my ol'mans lexcen......the fuel pump died......
i fitted a new pump and it almost pumped a full tank of fuel before it too died.....
so...after removing the new pump to fit another new pump.....we noticed the power plug on the actual
pump (in the tank) had loose connections and was arcing....it proceeded to burn out the terminals till they wouldnt make contact.....

so....before fitting the second new pump.....replace the connector and made sure it had good contact......
the thing is still running......many tanks later......


so...try checking as many connections as you can and see if any are burnt.....

another trick we used to do was.....run a wire from the fuel pump back to the dash and connect a small LED to it......
if the car stopped and the LED was still lit.....it eliminated all the wiring up till the pump.....

a fuel pump doesnt NORMALLY cut out whilst running.....it wont work after the engine has been switched off......
so...you are driving...all is well.....then you switch off......and it wont start.....

[DEFENDERZOOK]

reading your first post again......it sounds like coincidence your pump packed it in when it did......

it may be something else which is heat related......or affected by heat.....
such as coil.....air/vacuum leak.......fuel pressure reg as mentioned above (very common).....ignition module....?

there are many things it can be......the problem is its intermittent.....which means you simply guess at a common problem......
replace that component...cross your fingers and see if plays up again......
if it does play up again......you change another part......this is where dealerships benefit.....
they have other cars they can BORROW parts from.......till they track down the problem.....or even transfer it to the other vehicle........


connect also a fuel pressure guage along with the LED......it will tell you where to start looking for the problem......

[nobbydoldrums]

Does the disco have the fuel pump at the tank or up front?
I had very similar problems with a vn commodore... went to replace the fuel pump (which is inside the fuel tank) and the bottom of the tank was full of sugar....
The symptoms were: the car would run happily for about 20-30 mins and then buck under load or high road speed before cutting out completely. A 15 min rest and it would be ready to go again.
Whilst its probably unlikely you've go the same deal, perhaps the bottom of your tank is full of water or other crud like DRanged suggested?

[up2nogood]

does that mean the airflow wasn't at fault again at 1700 for a replacement???



Is that 1700 dollars for an airflow meter!? Holy sh*t.

[aclo]

I have had similar problems with my RR and a Disco i owned a few years ago. Turned out to be a wiring issue - clean all the earths first and then check for consistent 12 V at the pump. Most of the mising / idling / rough running problems I have had have been caused by faulty wiring or ignition. Worth a try??

Cheers
Brent

[Scouse]

so...after removing the new pump to fit another new pump.....we noticed the power plug on the actual
pump (in the tank) had loose connections and was arcing....it proceeded to burn out the terminals till they wouldnt make contact.....

so....before fitting the second new pump.....replace the connector and made sure it had good contact......
the thing is still running......many tanks later......


so...try checking as many connections as you can and see if any are burnt.....

The D1 has a link lead between the fuel pump & the main harness. It's not unknown to have this connection overheat & burn terminals.

Normally the replacement fuel pump doesn't work either unlike your case so I doubt this is your problem. You never know though.

[mcrover]

I will put my 2 bobs worth in and say check componants before you remove them, saves you a LOT af money.

Have you got a multi meter?

Lift the rear carpet, take the cover off over the tank and probe the wires for the fuel pump.

You should have more than 12v (between 12v and about 13.2/3v) constant and if not the fuel pump will only work intermittantly when pressure is low and it can start with very little load.

Once running it should be fine for a while until it gets a bit warm under pressure and needs a little momre power and will then cut out.

Most fuel lecky fuel pumps are like this.

If you are not getting north of 12v and it is actually south of the mark then start checking the positive feed but if you are constantly north of 12v then run a new earth or check the one you have properly with the continuity tester/or ohmeter.

Still if you find nothing wrong wire the pump direct and see if it kicks and if not pull it and see if it's blocked, if not blocked the replace the pump again.
Also check all your filters are clean and or new as a blocked filter can load up a pump and it will shut off.

Question, was the pump noisy before it quit?
Was there any other indication the air flow meter or throttle body I can't remember was faulty e.g. poor acceleration, heavy on juice, blowing black smoke?

Has it ever back fired?

I would have to read up on testing the ign module but from memory they just quit and thats it except for V8 commodores where they can come in and out for a while, gradually getting worse.

Failing all this, patch it up, sell it to some one you dont like and buy one with a 300Tdi in it.

Do the timing belt and forget about it for 60000km other than giving it a drink of clean RimX every 10k or so with a filter.

Have fun and if all else fails don't bring it to me as I no longer work on anything automotive that I dont own.

[4bee]

Whilst its probably unlikely you've go the same deal, perhaps the bottom of your tank is full of water or other crud like DRanged suggested?This is why every few months my fuel tank gets a cup of metho dropped into it. Makes a brine of any water & gets rid of it through the normal combustion process.

Maybe the regular addition of Mory's Upper Cylinder Lubricant helps lubricate the pump as well.


Air Flow meters
This crowd do repairs etc but I E-mailed them twice for something when I was having the V8i idle problem I never got the courtesy of a reply. Worth a shot I suppose. You may have better luck.;)

http://www.injectronics.com.au/Air%20Flow%20Meters,%20Air%20Mass%20Meters.asp

[PhilipA]

The most wear prone item in an injection system is the Throttle Position Sensor as it is like a volume control ie a needle scraping across a carbon track.
Over time they can get a gap, usually just off idle.
This causes a "tip in" miss and can sometimes have the car just stop while cruising along.

You can test it by putting a multimeter on the output and then just moving it slowly through it's range. Any deviation from a smooth increase or decrease of resistance or voltage means it's bad.
Regards Philip A