300tdi wont run after 5 mins or running???

hi ther i have recently brought an s reg disco with a 300 tdi

it has a fault i am struggling to sort out, once it starts up it will run fine for about 5 minutes then it will gradually sound like it is missfiring on a cylnder, and the accelerater peddle wont seem to make much affect and some times even stalls

i have replaed the fuel pump and i have tried a 4th injector, cleened out the sedement tank, put good diesel in repalced the fuel filter


if the fault is ther i can turn it off wait 5 minutes re start it and once again it will run fine for a further 5 minutes

any ideas much appreciated

does it still do the same if you remove the fuel cap? could also be a blocked cat?

i will try tommorw mate any one else have any other ideas???

It does sound like fuel starvation and as previously stated make sure the vent in the fuel tank is not blocked, but I would also inspect your fuel lines just in case it has been damaged / dented by off roading and causing a restriction. Obviously you have checked for leaks as this would also smell a bit. Have you checked you air filter condition as sometimes they become affected by damp and if really wet could be allowing moisture onto your MAF. Disconnect your MAF and see if it runs longer than the current 5 minutes. Would a blocked EGR cause these symptoms ? If you take it off to check I would be tempted to by a blanking kit beforehand and do away with it, it certainly improves performance.

It has a new air filter in it I will check them bits today remenee it runs for 5 minutes then it starts to run rough and missfire

I disconnected the air flow metre and took the patrol cap
Off still does it any ideas???

haza88 said:

I disconnected the air flow metre and took the patrol cap
Off still does it any ideas???

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Is the system bled correctly? I would start with the lift pump, only about 20 snakes, it's another trial & error one!

Surely if a pump works it works n won't die after 5 mins I think it is something electrical breaking down??

haza88 said:

Surely if a pump works it works n won't die after 5 mins I think it is something electrical breaking down??

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No!

Engine will usualy run with a knacked lift pump but will stall easily and have no power.

Only real electrical thing is the stop solonoid on the injection pump! Easily tested just run a + from the battery.That wunt stop it reving/lack of power though!

haza88 said:

i will try tommorw mate any one else have any other ideas???

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Two possible causes
Your pulling air into the fuel lines somewhere
You've got a tamper proof fuel cut off solenoid which is linked to your immobiliser thats playing up

i had problem like that the other day and found the sedimetior had a crack in the top of it bypass it.

I had same problem on my 300TDi RR Classic, mine was caused by gunge in the fuel tank that was restricting fuel flow into the pick up pipe.

Did urs both run for 5 minutes then run rough as surely if there's an air leak at all it would run like this all the time
?

mine ran ok then went rough but didnt cut out but when i dove it it spulted to a holt. 300tdi self bleeds so id think thats why it worked for so long

Hmm I'm going to try another injector as I'm not sure if the one I tried was definatly good

Does sound like air in the fuel lines ... after some time the air bleeds upwards, the fuel filter is full, so runs for a few minutes, air introduced to the system, starts to run like ****e. I'd check the fuel tank sender unit hoses .. lift boot carpets etc, undo six screws (angle grinder mostly) and have a look at the fuel lines and connectors. The nylon cracks and lets air in ...

Where are you? Put location into your public profile, maybe someone can have a look/listen and help you trouble-shoot it.

if air is getting in it will get in all the time??
it feels like and electrical fault the pedal wont make a difference to the engine when the fault occurs

fuel line is leaking in air check them all, also run the engine from a different source ie jerry can to lift pump?

What you need to do Harold its stick a dirty great big v8 in it and become a man! Get rid of the canal boat lump! lol!:crazy:

landylaw said:

What you need to do Harold its stick a dirty great big v8 in it and become a man! Get rid of the canal boat lump! lol!:crazy:

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huuush it down tell