RangeRovers.net Forum banner

1 - 15 of 15 Posts

·
Registered
Joined
·
7 Posts
Discussion Starter #1
Hi all, I was wondering if anyone may be able to help me out. My usual LR specialist isn't open right now so I need to resolve this one from home.

I was using my P38 on the farm at lambing a few weeks ago which involved running back and forth across a field for a while, nothing laborious or hard going on the vehicle. Field was pretty flat and speeds no more than 20mph but it was running smoothly the whole time and driving perfectly then it just suddenly cut out and wouldn't restart. I rescued it home a couple of days later and the engine would turn freely on the key. It would sometimes start and just idle for 30 secs but it wouldn't rev up and if it did run it would misfire very badly and then die.
The vehicles done 170k miles with LR fitting a replacement new engine at 80k and it's has full LR service history.

All the levels and fluids are good and putting a spare spark plug on each HT lead shows they all spark which discounts the coil I believe and this also shows the crank sensor isn't completely toast from what I've read. Each plug also smells of fuel so I assume the injectors are working okay? I whipped the plugs out too and although they aren't damaged in any way, the first four closest to the front were black/showing signs of running rich but the back four closest to the cabin were a more healthy colour.

The MAF was replaced about 200 miles/3 months ago when it wouldn't rev past 3.5k which fixed the issue.

I bought a Bearmach diagnostic tool and it shows no stored fault codes other than ABS ones and the EML isn't on. When I ask the tool to actuate the fuel pump you can hear working away too.

Given the sudden nature of the failure, does anyone have any clue where to look next?

Much appreciated. Ed
 

·
Super Moderator
Joined
·
1,917 Posts
My first suggestion would be crank position sensor as they often fail when they get hot which would also tie in with the running for a few seconds and then dying as it heated up. But you seem to have ruled that out with checking for a spark at the plugs. Checking the colour of the plugs won't really be a good indicator if it has been running around at low revs as it has.
 

·
Registered
Joined
·
7 Posts
Discussion Starter #3
I happened to have had a bosch crank sensor delivered the other day but I didn't fit it or even open it because I subsequently read that if the plugs still spark the sensor simply hasn't failed. I could go down the route of replacing plugs, leads, and the cam and crank sensor but I just don't know if the type of failure shows I'm barking up the wrong tree. I don't know the P38 well enough to recognise any trends yet...
 

·
Registered
1995-2002 Range Rover P38A
Joined
·
471 Posts
having a similar problem my self , i have checked all the obvious things idle stepper motor maf cps nothing i am now waiting for it to stop raining so i can check for air leaks as mine behaves similar to the issues with the supercharger issue that was here last week, check the o'ring on the maff conection ?
 

·
Registered
Joined
·
7 Posts
Discussion Starter #6
That's a good shout. I suppose it's possible for the pump to prime but not at the required pressure.
 

·
Registered
1995-2002 Range Rover P38A
Joined
·
114 Posts
Like Richard said, crank position sensor likely. I've had the same experience. CPS is behind a metal cover. Wiring is hard to navigate. Tie a long strong thin string to the old wiring before you pull it out and then tie that end to the new wiring when you go to install. Still not easy as it is back in between the engine and firewall.
 

·
LEGACY VENDOR
1995-2002 Range Rover P38A
Joined
·
4,174 Posts
If you've got a spare crank sensor then I'd replace it anyway - they are known for failing and about the the only sensor on the engine that will cause it to NOT start. pretty much everything else will still let it start, but it'll run like a sack of spanners.

It could be it's partly faulty so you still get spark, sometimes... the ECU uses the crank sensor as the basis for it's timing for the spark, so if it's intermittent, then it might work sometimes but not others.

If you swap it and it doesn't fix it, then it's still worthwhile having done as the do just randomly fail, so having a new one in there is peace of mind at the very least
 

·
Registered
Joined
·
7 Posts
Discussion Starter #9
Thanks gents. I'll put the new crank sensor on and order the attachment to allow a fuel pressure read and let you all know how I get on. I did try and disconnect the MAF at the start just in case it went completely haywire but no difference. If there's still no joy, I'll have to continue pestering you all.
Thanks, Ed
 

·
Registered
Joined
·
59 Posts
+1 for crank angle sensor , mine wouldnt rev over 2000rpm sometimes it wouldnt start . Replaced & problem solved like above it aint easy to get it out
 

·
Registered
Joined
·
7 Posts
Discussion Starter #11
Quick update as promised - I replaced the crank sensor but no joy - still barely runs with bad misfire so I'll get a read on the fuel pressure and see how it compares.
 

·
Registered
Joined
·
7 Posts
Discussion Starter #12
Okay, so fuel pressure is 45 psi on ignition II, and around 50 psi on cranking. Is there anything conclusive about that i.e. pressure is good so not reason for the issue etc?
Thanks
 

·
Premium Member
Joined
·
1,318 Posts
Fuel pressure is as per spec. And you say you have spark (on all cilinders?). That does not leave much else. If some plugs look fouled, I'd change all of them. The GEMS can give trouble when plugs get flooded and wont easily recover. Bosch seems to be more tolerant, but definitely worth a try. Also check for any loose connectors or damaged wiring.
 

·
Registered
Joined
·
7 Posts
Discussion Starter #14
Fuel pressure is as per spec. And you say you have spark (on all cilinders?). That does not leave much else. If some plugs look fouled, I'd change all of them. The GEMS can give trouble when plugs get flooded and wont easily recover. Bosch seems to be more tolerant, but definitely worth a try. Also check for any loose connectors or damaged wiring.
Thanks for the reply. Yup, all eight spark and it was almost as if a switch was just flipped when it stopped running so I thought wiring too but haven't found anything yet. I think I will replace the plugs as well as confirm a compression test. Thanks again.
 

·
Registered
1995-2002 Range Rover P38A
Joined
·
471 Posts
use a multimeter to check your coils as i think that's my problem, faulty coil pack. you have two coil packs .
 
1 - 15 of 15 Posts
Top