I have had unrelenting problems with starting my 2004 Peugeot Partner 1,9 diesel. It has 230 000 km on the odo and I’ve spent more than R10 000 at the “experts”, who’ve attempted to remedy the situation by performing an injector pump rebuild. The result was a vehicle that ran for three months after the first “expert” investigated and only one month after the second. Under normal conditions the engine starts immediately, hot or cold, runs smoothly, revs freely, is light on fuel and pulls as strongly as can be expected from a normally aspirated diesel motor of its engine capacity. During the intermittent starting problem, the engine will crank, but won’t start. Having had lengthy discussions with numerous technically competent individuals, the obvious conclusion seems to be a faulty fuel-shutoff solenoid or immobiliser. Is the best solution to fit a new shut-off valve and bypass the immobiliser?
MICHAEL HALL
Rustenburg
Answer: The fuel injection system on this engine is fairly simple: a mechanical injector pump supplies the fuel to mechanical diesel injectors (not a common-rail system). The injector pump is responsible for sucking the fuel from the tank and then it has four internal plungers (pistons) that supply the correct amount of fuel to each injector depending on engine speed and accelerator position. The way the engine is stopped is to switch off the fuel supply at the pump via the solenoid shutoff valve.
If the engine cranks over then we are not sure that the immobiliser is at fault, because cranking would not be allowed in the immobilised state. For peace of mind you should do a compression check on the engine owing to its mileage. It would also be good to check the status of the solenoid shutoff valve to know if fuel is directed to the pump during cranking (you can also remove an injector pipe to see if diesel was being delivered).
Usually these valves are closed by default and need a voltage signal to open. Once you’ve determined which wire supplies this signal then you can tap into the wire to measure whether it’s relaying current using a voltmeter (or even splice in a bulb with connection to ground that is visible). Now you should be able to tell if the valve is open or closed. If the engine fails to start while the valve is open then there is another problem. We have heard that debris in the tank can clog the pick-up filter and prevent fuel from reaching the injector pump. That will be our guess if it is not a solenoid valve, fuel delivery to the injectors (including pressure) or low compression problem.
