Disco 2 / Cranks but won't start

squirt

Well-known member
Nov 13, 2008
824
13
Los Angeles
I didn't try to power the fuel pump directly. Not sure how to do that. I'm assuming that I have to remove the plug, identify the pos and neg pin on the pump and apply power to it?

Power input at the fuse and relay: i checked voltage on both ends of the fuse. I removed the relay, tested it on the bench and it clicks. In other words, I don't think that I checked if I'm getting power input. Will do.

Correct, now is persistent. Every time I check or do something to it, I try to start the engine. It's still doing the same thing: cranks, no start and backfiring very, very load.

I'm on my way to the mountains for a weekend camping trip. I'll be working on this late Sunday or Monday and report back as soon as I can.


Regarding powering the pump directly - If it was mine, I'd just connect a 12v jumper pack or other spare battery to the positive and negative leads on the pump to get it to run.

The part I still don't get is the backfiring. Backfiring in my experience is due to incorrect timing or lack of sufficient spark that's causing the fuel to ignite outside the combustion chamber. If you have at any recent point had the plug wires off the plugs or coils, I'd double and triple check them.
 

joshasbury

Member
Jun 21, 2016
8
0
Hamilton, OH
I had the same issue occur a couple of weeks ago. We replaced the relays coming out of the fuse box and tested the crank position sensor. It would crank and intermittently start. However, the battery still wouldn't consistently maintain charge, so I bit the bullet and put a new alternator in. 5 days on, everything is working fine.

Depending on your level of patience, I'd recommend going that route.
 

Explorer0863

Well-known member
Nov 22, 2010
52
0
Orlando/San Juan
It has been a while and I received a couple of messages, so let me update this thread. A new contract at work and the fact that I am very frustrated with the Disco II prevented me from working consistently on this issue.

As of today, it's still not running. The same: crank, but it won't start. The fuel pump is good and I have good PSI. The new crank position sensor didn't solve the problem. Current at the spark plug wires was "weak", so I replaced both coil packs and wires. That didn't solve the problem either. The current it's still weak.

I was thinking replacing the engine computer, but it is my understanding that if I replace the computer, it will require reprogramming. Is that true?

Someone here mentioned a fuse box. I still have the original interior fuse box. That's the one that made the A/C motor blower inop. Before I spend and waste more time and money, I am going to re-install it this week and see what happens.

A friend of mine told me today that he had a similar problem with his Disco II last year. After a lot of work, and testing different components, he ended up replacing the engine compartment fuse box and that solved the problem. I guess that I may try that as well if replacing the interior fuse box doesn't work.

If nothing works, it looks like this is going to be a parts car very soon...
 

Explorer0863

Well-known member
Nov 22, 2010
52
0
Orlando/San Juan
Final report and outcome: the problem was the interior fuse box.

I re-installed the old one that I had removed last year due to the A/C blower issue. Had to reset the alarm and it started on the first attempt. I don't have A/C again, but at least the engine is running fine.

Many thanks to all of you for your help and suggestions.
 

pdogg

Well-known member
Jul 18, 2005
1,216
29
Phoenix, AZ
Something in this thread caught my attention, you mentioned the previous owner removed the Catalytic converters.. how can this work with front and rear O2 Sensors?
 

squirt

Well-known member
Nov 13, 2008
824
13
Los Angeles
you can trick the 02s as well

I tried it on an offroad rig and it worked like a champ. Not an endorsement by any means but it is possible..

example.
http://www.frsport.com/CEL-Fix---Ch...rI01dJhgLG6-i2jNHuGGRo306Ujaaxv3A8xoCO-nw_wcB


They also sell these spacers with mini-cats built in. Pretty easy to find. In my experience, vehicles will often have emissions output which is well within standards (sometimes even sans cats), but the OBD efficiency threshold is so strict that it's easy to trigger a CEL.
 

ozscott

Well-known member
Final report and outcome: the problem was the interior fuse box.

I re-installed the old one that I had removed last year due to the A/C blower issue. Had to reset the alarm and it started on the first attempt. I don't have A/C again, but at least the engine is running fine.

Many thanks to all of you for your help and suggestions.

I had exactly the same issue. I think the printed circuit board die (dual row). I used a second hand one and all good. Trouble is what do we do when there are no second hand ones. It's a deal breaker. Perhaps get electronic tech to find the fracture and repair.

Cheers