director_steve
Active Member
Thanks guys.
Truck was running nicely until this morning....:violin:
Jumped in, and it felt like it was running on about three cylinders. Really horrible. It clears with some throttle, but not immediately. Sounds like an ignition problem to me, what do you chaps think?
Happened on the day i have to drive 300 miles
My plan was to change the gearbox and transfer box this weekend. Think i'm going to be doing a bit more than that now....
Truck was running nicely until this morning....:violin:
Jumped in, and it felt like it was running on about three cylinders. Really horrible. It clears with some throttle, but not immediately. Sounds like an ignition problem to me, what do you chaps think?
Happened on the day i have to drive 300 miles
My plan was to change the gearbox and transfer box this weekend. Think i'm going to be doing a bit more than that now....
director_steve
Active Member
well, i gave up and took it to a gentleman down the road who fixes cars from his garden shed (best kind of garage!). Turns out his son has Land Rovers and knows them really well (but his son's not about until Tuesday...).
He confirmed it wasn't an ignition problem at all, and that the problem was the mixture. He said he'd a similar issue before on a disco 3.9, and it was most probably the Coolant Temperature Sensor and that unplugging it would probably help. I did, and true enough- it is at least now driveable again.
I suppose now i have to replace the coolant Temp sensor again (although the resistance seems to be spot on) and then work back down the loom, trying to ascertain if the wiring is sound all the way back to the ECU...which sounds like a fun day/week/month.
S
He confirmed it wasn't an ignition problem at all, and that the problem was the mixture. He said he'd a similar issue before on a disco 3.9, and it was most probably the Coolant Temperature Sensor and that unplugging it would probably help. I did, and true enough- it is at least now driveable again.
I suppose now i have to replace the coolant Temp sensor again (although the resistance seems to be spot on) and then work back down the loom, trying to ascertain if the wiring is sound all the way back to the ECU...which sounds like a fun day/week/month.
S
director_steve
Active Member
Update:
I haven't yet had chance to spend much time on the engine as i've just replaced the gearbox, transfer box, props, handbrake etc etc etc. So i've yet to check the resistance at each end of the loom. I also intend to check the resistance on the EFI sensors- any tips welcome!!! I'm planning to do this tomorrow.
I have replaced the ECU, which made it run perfectly when i took it round the block...until i came to park it and nearly stalled it- after this it started to run REALLY rough and would barley move- backfiring etc. It was almost like the revs dropped below a certain point and the ECU freaked out, throwing it into a kind of limp mode. Any ideas?
Cheers,
Steve
I haven't yet had chance to spend much time on the engine as i've just replaced the gearbox, transfer box, props, handbrake etc etc etc. So i've yet to check the resistance at each end of the loom. I also intend to check the resistance on the EFI sensors- any tips welcome!!! I'm planning to do this tomorrow.
I have replaced the ECU, which made it run perfectly when i took it round the block...until i came to park it and nearly stalled it- after this it started to run REALLY rough and would barley move- backfiring etc. It was almost like the revs dropped below a certain point and the ECU freaked out, throwing it into a kind of limp mode. Any ideas?
Cheers,
Steve
classic kev
Well-Known Member
I would suggest the best thing you can do is get yourself an ECUMate so you can plug it in and see what the efi is doing. These aren't expensive and are a useful tool.
Unless you have a good understanding of what does what and how I suspect you are just going round in circles. It sounds like the ECU is in limp mode and therefore fuel is just being dumped in to the engine, yes it will run and the more throttle you give it the better it feels but that is only because with a wider throttle there is more air going in bringing the air/fuel ratio closer to where it ideally should be.
Rough running can be any one or a combination of issues, so either understand what all the sensors are and what they do then check/test individually or get it plugged in somewhere but don't forget that the ecu itself or the loom can cause issues, so if all the sensors check out, test again with a different ecu. You might also have to test when the engine is cold and again when up to temperature, be aware getting these things to work properly can be a real test of patience, you just have to stick with it.
director_steve
Active Member
Thanks Kev, I've changed the engine ECU so i know it's not that. I did ask a garage to diagnose it with their fault reader, but they couldn't get any diagnostics to work. so i'm back to square one.
Going round in circles is exactly what it feels like!
I tested all the sensors with the old ecu, but only at the engine end. Today i'm going to test the all with the new ECU at both ends...theoretically.
Steve
Going round in circles is exactly what it feels like!
I tested all the sensors with the old ecu, but only at the engine end. Today i'm going to test the all with the new ECU at both ends...theoretically.
Steve
Steve
more and more people are suffering these sorts of woes with their geriatric EFi systems - my mate Derek at Derek Allfrey Landrovers is seeing it all the time.
He looks after about 200 old discos and various RRC's - there is always one in the workshop needing a new dizzy or ecu or injector or something like that.
Derek's advice now - switch to carbs mate - easy to install - tune and forget - more torque and power as well if you go for an edelbrock 500.
Early last year he had in a disco 3.9 that was doing about 8 mpg and horrendous emissions - was in for service and MOT - the client was availed of the info about the edelbrock setup and agreed to have it done - parts are about 600 quid - inlet, carb, gaskets, regulator, air cleaner, and it takes about 6 hours to do the swap.
The car was transformed - emissions were really good (Edelbrock are in California so all there stuff is tuned for low-emissions anyway) and the car went like a rocket.
Since then he has converted about a dozen or so - all with no problems - you can even buy a complete LPG kit for it from RPi.
Just a thought based on some very positive experiences - as long as your dizzy,leads and coil are in good order this setup will give you the reliability you are looking for.
The extra wallop is a bonus too!!!!!!
more and more people are suffering these sorts of woes with their geriatric EFi systems - my mate Derek at Derek Allfrey Landrovers is seeing it all the time.
He looks after about 200 old discos and various RRC's - there is always one in the workshop needing a new dizzy or ecu or injector or something like that.
Derek's advice now - switch to carbs mate - easy to install - tune and forget - more torque and power as well if you go for an edelbrock 500.
Early last year he had in a disco 3.9 that was doing about 8 mpg and horrendous emissions - was in for service and MOT - the client was availed of the info about the edelbrock setup and agreed to have it done - parts are about 600 quid - inlet, carb, gaskets, regulator, air cleaner, and it takes about 6 hours to do the swap.
The car was transformed - emissions were really good (Edelbrock are in California so all there stuff is tuned for low-emissions anyway) and the car went like a rocket.
Since then he has converted about a dozen or so - all with no problems - you can even buy a complete LPG kit for it from RPi.
Just a thought based on some very positive experiences - as long as your dizzy,leads and coil are in good order this setup will give you the reliability you are looking for.
The extra wallop is a bonus too!!!!!!
marccleave
Active Member
Interesting.
)
More torque and power? Remember that if someone is going from a broken, temperamental or not correctly setup or even worn out EFI system to a brand new properly tuned carburettor of course the engine is going to run properly.
Again see above, I'm not surprised it was transformed going from something that isn't working correctly to something that is.
£600? If you want improvements then for a little bit more, some learning, etc then why not fit megasquirt? Not only will that be a far better improvement on the original injection system but you will also not have potential problems with running the car at silly angles like you may do with a carburettor. Oh and with EDIS your 'vunerable' rover v8 is now water proof. Bye bye original injection and ignition system.
But if perhaps 'lecky' things aren't someones special point then just bringing the original EFI system back to its working state will be better & cheaper. Heck, you could even go and buy working flapper/hotwire injection systems a few times over for the price of a carburettor & new manifold. Problem solved and a lot cheaper!
Now I didn't want this to come across as antagonist or attack you specifically. I just see a lot of stick given to the Rover V8 injection systems and everyone throws "change it to carbs mate!" instead of being methodical and fixing what is broken.
As for the OP, classic kev has given some great advice. When funds allow, an ECUmate would be a great investment. You can see what is happening while the engine is running, read faults and clear them without having to do it the poor mans way of unplugging the ECU, waiting and putting it back in again.
The test of patience is very true. You do have to stick with it and make sure you use methodical, logical problem solving. If you just change this and that then you will go round in circles and potentially replace things that don't need replacing. Test don't guess! Good luck Steve!
Yes, that makes sense, more and more Land-Rovers with flapper or hotwire EFI are getting older. Okay, some might say they're not the best systems to begin with, but as things get older they wear out.
Those things you mentioned make sense. Distributors are mechanical and spin around doing their job, they have moving parts so of course they're going to wear out slightly. ECUs may not be mechanical but they do have solder joints. While sitting in a car for ~20 years, vibration, temperature etc may cause bad solder joints, then giving you a dodgy ECU.
Tune and forget? Okay so you tune it and forget. You've put a new carburettor system on now but look at carburettor systems that are now 20 years old, they're now worn out and need rebuilding or replacing. So what happens in another 20 years time when this system starts going dodgy? Aad don't tell me the Land-Rover will have been scrapped by then, its a Land-Rover remember? We rebuild them and keep them going! (For some strange reason!
)More torque and power? Remember that if someone is going from a broken, temperamental or not correctly setup or even worn out EFI system to a brand new properly tuned carburettor of course the engine is going to run properly.
In that case there was definitely something wrong with the injection/ignition system and or they were driving it like they stole it!
Again see above, I'm not surprised it was transformed going from something that isn't working correctly to something that is.£600? If you want improvements then for a little bit more, some learning, etc then why not fit megasquirt? Not only will that be a far better improvement on the original injection system but you will also not have potential problems with running the car at silly angles like you may do with a carburettor. Oh and with EDIS your 'vunerable' rover v8 is now water proof. Bye bye original injection and ignition system.
But if perhaps 'lecky' things aren't someones special point then just bringing the original EFI system back to its working state will be better & cheaper. Heck, you could even go and buy working flapper/hotwire injection systems a few times over for the price of a carburettor & new manifold. Problem solved and a lot cheaper!
Yet another thing that possibly isn't taken care of properly, Rover V8 igntiion system, but thats simple enough and I won't go into it.
Now I didn't want this to come across as antagonist or attack you specifically. I just see a lot of stick given to the Rover V8 injection systems and everyone throws "change it to carbs mate!" instead of being methodical and fixing what is broken.
As for the OP, classic kev has given some great advice. When funds allow, an ECUmate would be a great investment. You can see what is happening while the engine is running, read faults and clear them without having to do it the poor mans way of unplugging the ECU, waiting and putting it back in again.
The test of patience is very true. You do have to stick with it and make sure you use methodical, logical problem solving. If you just change this and that then you will go round in circles and potentially replace things that don't need replacing. Test don't guess! Good luck Steve!
An properly set-up edelbrock 4 barrel carb and hi-rise manifold will always make more power and torque than a primitive efi system like Hotwire and fuel economy is similar.
That is why V8 developments use one for their dyno runs.
Dom at TVR power will tell you that as well.
Kits can be had to counter the off-road issue for 45 quid
I don't think you can buy a brand new injection system for 600 quid -
AFM, ECU, injectors, loom rail, etc
That is why V8 developments use one for their dyno runs.
Dom at TVR power will tell you that as well.
Kits can be had to counter the off-road issue for 45 quid
I don't think you can buy a brand new injection system for 600 quid -
AFM, ECU, injectors, loom rail, etc
director_steve
Active Member
Thanks Chaps- some interesting points. I did manage to test the EFI system by being methodical and Careful, and writing it all down. After testing the loom and the sensors, all seemed to be working absolutely fine. But i did stumble across a fuel pump relay that really badly corroded. I replaced this (and the other one for good measure), and the engine now runs 500% better, although still not perfect.
Having now isolated that the EFI system is now fully functional, it's gone off to a Landy specialist to see if he can pinpoint why it's not 100%.
I completely agree that getting diagnostics on the truck would be best, and i'm looking into this for when i get her back. I also spent a good deal of time at the megasquirt stand at the indoor 4x4 show recently- definitely on my shopping list!
Thanks again you lot!
I'm not sure when i'll get her back (fund allowing). The choices i gave myself was to get it fixed, and sell a kidney to pay for it. Or sell it faulty, make a big loss and buy a cheapy disco to play with. But, sad though it is, i'm so attached to my fender, warts and all, that i reckon i can live without 2 kidneys for the privilege of keeping her.
S
Having now isolated that the EFI system is now fully functional, it's gone off to a Landy specialist to see if he can pinpoint why it's not 100%.
I completely agree that getting diagnostics on the truck would be best, and i'm looking into this for when i get her back. I also spent a good deal of time at the megasquirt stand at the indoor 4x4 show recently- definitely on my shopping list!
Thanks again you lot!
I'm not sure when i'll get her back (fund allowing). The choices i gave myself was to get it fixed, and sell a kidney to pay for it. Or sell it faulty, make a big loss and buy a cheapy disco to play with. But, sad though it is, i'm so attached to my fender, warts and all, that i reckon i can live without 2 kidneys for the privilege of keeping her.
S
