Series Land Rover (Australia & NZ)
Serving the Series 1, Series 2, Series 3 and other Land Rover communities worldwide.

There are a range of possible reasons why the diesel engine on a Series Land Rover could be having problems idling smoothly and without stalling. The main reasons are dealt with by category below. As with any fault diagnosis we should be prepared to allow for there being more than one cause of the problem. So check all categories even if a fault has been identified already.

Is it a high mileage engine?
If so, it could have developed wear in the timing chain and tensioner - this can affect the timing of the distributor pump. So if the timing of the pump is considered to be correct then the solution is to fit a new chain and tensioner.

Are there any fuel pipe leaks?
These will cause air to enter the fuel at an irregular rate and dilute the fuel/air mixture below what it should be. The engine will struggle to idle and will fire irregularly.
Carefully check all fuel pipe junctions and their unions. A loose connection on the suction side of the fuel pump will draw in air most easily. Tighten any loose joints you may find.

Fuel injector problem?
The easiest way to diagnose and identify a faulty injector is to loosen the fuel pipe connection leading to it, whilst the engine is running. If the injector is good, then there will be a marked drop in engine idling but if there is little change in engine performance then that injector is faulty and needs to be professionally cleaned or replaced. If removal is not an option, then there are some fuel injector cleaning additives avaliable that can be put into the fuel to clean the injector over time.

Fuel filters need changing?
If it has been a while since they were changed then some poor quality fuel could have caused significant blockage. Replace the filter(s).

Fuel return pipe partially blocked?
Not a common fault but could lead to rough idling. Easily checked by removing the pipe and blowing though it to check for obstruction.

Injector pump have incorrect timing?
The timing is set by loosening the pump and turning it, but the appropriate workshop manual needs to be consutlanted for the relevent procedure.