Hello all
I am having a problem with my 2002 daf lf 45 130. All was well until last week when i noticed on tickover the engine seems to be hunting. It will not idle smooth like it used to. It drives fine with no power loss. Is this a common issue with these as ive only just bought it??
I don’t know anything specific to the LF engines as I’ve never run one, but…
It could need a valve adjustment, if the timing’s out it is more noticeable at tick over, even if it isn’t the cause, it’s a good thing to get done anyway.
Other things to check are fuel lines, there may be a small hole which is overcome when pressure rises as you put more fuel to it with higher RPMs, Could be fuel filter, although that usually shows up at the top end first, same with the air filter.
Cheapest fix is to drop a load of Lucas injector treatment in the fuel tank (follow the guidlines on the can for amounts) that will help clean the injector nozzles and it won’t do any harm, even if it doesn’t cure the problem.
This is a ■■■■■■■ common rail.Check wiring security under rocker cover where it plugs into the injector coils,check crank sensor and exciter ring for wobble or a loose pickup.
If it gets a fluctuating voltage on tick over this will make it lumpy but as the RPM increases the signal voltage will increase and the missfire will disappear.
If all seems ok check the compression you might have a leaky valve or a bad injector.
Are you sure it’s definitely changed as if it’s got that 3.9 engine it shares with the Eurocargo it does have a very funny distinctive idle.
Own Account Driver:
Are you sure it’s definitely changed as if it’s got that 3.9 engine it shares with the Eurocargo it does have a very funny distinctive idle.
thanks for all the replies. Yep its definately changed and now i have an orange engine waring on the screen. The power has dropped off too, prob in limp mode 
Where abouts are you? I’m a Daf specialist in the London / Essex area if you need some one to look at it.
I’ve got a diagnostics computer so will be able to pinpoint why the engine warning is on.
You probably have 1 or more injectosr with excessive leak off
injectors 
not cheap either had the six done on my lf came to thick end of a grand
R975ENC:
injectors
super
i better get them checked so. Where is the diagnostic port located on these?
you disconnect the leak of pipe at the rear of the cyl head and fit a pipe in to a jug ,and a plug to the pipe you have removed ,take of number 1 injector pipe,and fit a plug to the common rail…Run the engine for 1 min and measure the amount of leak off ,you are allowed a max of 30 ml per inj…so the injector that is disconnected and the leak off is less than 30 ml is the faulty inj replace inj or injectors and test them all again ,as once a faulty inj is replaced the next weak injector can fail…you need to purchase or make up pipe and appropriate plugs
Mine is doing this, not run it for a while but it hunts around up and down continuously on idle. It’ll sound sweet for a few seconds then go really rattly for another few, then return to sounding nice and repeat that.
I just put it down to it having been stood for a while but I can’t take it out because its not road legal currently. Has yours has a long run recently or just sat about?
Ian G:
Mine is doing this, not run it for a while but it hunts around up and down continuously on idle. It’ll sound sweet for a few seconds then go really rattly for another few, then return to sounding nice and repeat that.I just put it down to it having been stood for a while but I can’t take it out because its not road legal currently. Has yours has a long run recently or just sat about?
yep, its been lying up a long time, and onlt recently been put on the road, and yep its just had a long run when this started
norb:
you disconnect the leak of pipe at the rear of the cyl head and fit a pipe in to a jug ,and a plug to the pipe you have removed ,take of number 1 injector pipe,and fit a plug to the common rail…Run the engine for 1 min and measure the amount of leak off ,you are allowed a max of 30 ml per inj…so the injector that is disconnected and the leak off is less than 30 ml is the faulty inj replace inj or injectors and test them all again ,as once a faulty inj is replaced the next weak injector can fail…you need to purchase or make up pipe and appropriate plugs
great info there thanks 