Limp Mode For No Reason??

Hi guys, so my defender 110 has been going into limp mode whenever being driven at high speeds for a long period of time along the motorway and I have no idea why, it’s been back and forth to a mechanic for quite some time now and I’m not entirely convinced they know exactly what they’re looking for, I just had the fuel pump reprogrammed and had it replaced a little while ago, I’m wondering if this has anything to do with the turbo system? Heard allot about EGR valves being a culprit for this type of problem but I’m unsure of how to test if this is the case for myself, mechanic is saying something about replacing fuel injectors too but I don’t want to keep spending loads of money for nothing to work, thanks

what codes are given after this presumably the garage has read them

jamesmartin said:

what codes are given after this presumably the garage has read them

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I’ll enquire when I’m down there again on Friday to take the vehicle back to them, last time I used my uncles code reader no codes came up, which is confusing to me, maybe it’s worth getting my own to plug it in and see tho?

It will not go into limp mode for "no reason". You need the fault codes to start the investigation. If your garage / mechanic can't read the codes they have zero chance of successfully changing the injectors, they need programming into the management system. Get the fault codes and post them on here, I have a list of the codes handy.

Wimblowdriver said:

It will not go into limp mode for "no reason". You need the fault codes to start the investigation. If your garage / mechanic can't read the codes they have zero chance of successfully changing the injectors, they need programming into the management system. Get the fault codes and post them on here, I have a list of the codes handy.

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I’ll get the codes as soon as I can, it will probably have to be Friday at the earliest sadly, I think the garage said something about the code meaning something to do with “overboost” or something like that? I’m not very knowledgeable about this kind of stuff and haven’t owned my defender for too long, do you have any idea what that might mean?

Wimblowdriver said:

It will not go into limp mode for "no reason". You need the fault codes to start the investigation. If your garage / mechanic can't read the codes they have zero chance of successfully changing the injectors, they need programming into the management system. Get the fault codes and post them on here, I have a list of the codes handy.

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Is there any chance that this may be able to read the codes? I might be able to get someone to pick it up from Halfords for me before Friday

OwenP02 said:

I’ll get the codes as soon as I can, it will probably have to be Friday at the earliest sadly, I think the garage said something about the code meaning something to do with “overboost” or something like that? I’m not very knowledgeable about this kind of stuff and haven’t owned my defender for too long, do you have any idea what that might mean?

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over boost wont be injectors its a turbo or turbo actuating servo,presumably its the puma engine with vnt turbo,the vanes can stick or servo doesnt operate fully

jamesmartin said:

over boost wont be injectors its a turbo or turbo actuating servo,p[resumably its the puma engine with vnt turbo,the vanes can stick or servo doesnt operate fully

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What would I do to fix this then?

get codes read,then cleared the rechecked when it does it again,if its the same id look at turbo but its a chunk of money without been pretty sure

Don't

OwenP02 said:

What would I do to fix this then?

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Don't have a Defender, but this has happened to me in a TD5 Disco.
A turbo is a turbo, Variable vane or not.
Start by physically checking that the wastegate actuating rod from the turbo to the wastegate can operate. Also check the security of the wastegate mounting studs/nuts etc. The actuator can stick and the wastegate can come loose. The end result is the same, if the wastegate can't open, the turbo overboosts, the ECU reads this as overfuelling (I think) and then cuts the fuel and puts it into limp mode till you stop and turn the ignition off then restart. Happens when trying to drive sensibly up hills or accelerating fairly hard or harder.

I had the same problem, more so going up long hills on the motorway. I would have to keep stopping on the hard shoulder turn the engine off restart and it would fix the problem till the the next long hill. Got the turbo rebuilt and it’s been fine ever since....

Stanleysteamer said:

Start by physically checking that the wastegate actuating rod from the turbo to the wastegate can operate

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That can be ruled out. The tdci turbo does not have a waste gate. I'll see if I can upload the relevant pages from the workshop manual for the variable vane on the turbo.

Some info attached. Fault codes for turbo to follow. But be aware it might not be the turbo which is at fault, we need to see the fault codes.

Turbo fault codes ------

I’m going to get the codes as soon as possible, I’ll either have to get them off of the mechanic on Friday or get a code reader and read them myself, is it pretty safe to say that this fault is with the turbo system and nothing else tho?

Awkward said:

I had the same problem, more so going up long hills on the motorway. I would have to keep stopping on the hard shoulder turn the engine off restart and it would fix the problem till the the next long hill. Got the turbo rebuilt and it’s been fine ever since....

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That is the exact problem I’m having

OwenP02 said:

I’m going to get the codes as soon as possible, I’ll either have to get them off of the mechanic on Friday or get a code reader and read them myself, is it pretty safe to say that this fault is with the turbo system and nothing else tho?

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most likely, a variable vane turbo alters the vane angle to control the boost,if theres a fault with vanes or servo then boost cant be controlled ie ecu will see wrong expected boost pressure at certain times of the engines performance,going up motor way hills is going to be one of the times turbo boost is the greatest

jamesmartin said:

most likely, a variable vane turbo alters the vane angle to control the boost,if theres a fault with vanes or servo then boost cant be controlled ie ecu will see wrong expected boost pressure at certain times of the engines performance,going up motor way hills is going to be one of the times turbo boost is the greatest

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If this is the case what should I do?

OwenP02 said:

If this is the case what should I do?

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get codes read, cleared and read again

Thanks for the help guys, I’m gonna pass all of this information off to the mechanic to see what they can do, I’m not entirely sure they knew what the problem was but you guys seem to have a good idea, if they keep messing up fixing the fault does anyone know anyone good in Kent I could take my defender to?