Fuel pump and relay woes!

[Atomik99disco1]

Started having issues getting my 99 Disco 1 v8i advanced evaps 4.0 only 93K with no Mods.
I would have to turn it over 4-5 times and pump the accelerator rapidly and it would chug back to life. On the highway I noticed that it would cut in and out as if the coil pack was going out. Luckily I made the 290 mile trip back home! Since then no go!
The fuel pump wasn't coming on when I switched the ign. to pos. 2. I tested the continuity which thankfully didn't read '0' and voltage at the pump read 5.04v? after some research, I found out it's supposed to be getting 12+ volts for a few seconds to get the fuel rail primed, then drops to 5.04v.
Not getting the 12v?
thought maybe the multifunction relay was jacked up so I cracked it open, very carefully mind you, and its doing its thing, which means the ECU is also! Whats equally aggravating is that I was hoping it would be a cheapo relay behind the RH kick panel but it is not used with my specific odd-ball model!
What am I missing? I would seriously appreciate any input.
Last edited by Atomik99disco1 : 01-27-2010 at 02:27 PM. Reason: FORMAT

 

[joey]

2 things... have you replaced the fuel filter and have you checked the fuel pressure at the fuel rail? It is possible that it is not a fuel problem...

 

[Atomik99disco1]

No fuel at the rail. I'm actually in the process of changing the fuel filter. It's been raining cats 'n' dogs the past couple weeks making it a pain to work on.

 

[Atomik99disco1]

sumthin' to add

I charged the battery 2 days ago because it was getting a little tired and afterward it cranked the motor like a firecracker! It's a new battery. Anyways, today I tried to get it going with some starting fluid and the battery was low. "Strange" It fires up with a squirt! Is it possible that some sensor is stuck discharging the battery and messing with the ECU?

 

[Atomik99disco1]

charged the battery & removed the fuel relay, reads 12.74v. removed the positive battery cable and installed a test light. A constant pulse. removed fuses one by one. the only one that made any difference was Satellite 2 #6 20a Trailer lights, auxiliary. It just made the pulse really faint but nothing stopped it.

 

[Atomik99disco1]

constant draw

I figured it I had nothing else to lose today so i disconnected the positive battery cable and installed a test light. There was a constant pulse. So I started to remove fuses one by one to see where the draw was coming from. Only one made a difference (satellite 2 fuse#6) Trailer lights, auxiliary. and the difference was nothing to write home about! The pulse of light just got really faint.

 

[Disco Mike]

First 12.7 volts are too low, you need somewhere between 13.6 and 14.4 volts.
Second, the fuel pump only runs for 3 to 5 seconds, just long enough to prime the fuel rails, then it shuts off if the engine doesn't start.
That all being said, you need to try priming the fuel system, try turning the key to the 2nd position, hold it for 5 seconds and shut it off. Do that at least three times, then trying starting the engine. If it runs, then you have a bad valve in the pump, allowing it to bleed off, if that is the case, you will need a new pump.
If it still doesn't start, you could have a failed crank sensor that can turn off the pump when trying to start.
Let us know what happens and if you have any fuel pressure.