Fuel Pump Fault caused by Distributor - Primera P11 (Series 3)

I have pulled a spark plug and it was quite wet. On turning the engine It did spark against the block, albeit a weak spark rather than a strong blue one. The plugs themselves are relatively new and there were no warning symptoms such as misfiring, the car simply started for about 1 second yesterday then stopped. Since then I have cycled the ignition to prime the fuel system using the initial 2 second bursts, then tried to start the engine at which point it caught briefly but did not start. Suspecting a fuel fault I removed the fuel feed from the engine side of the filter and tested the pump operation on Ignition-On and Starting routines.

I'm thinking that : (a) the car isn't starting because the fuel pump isn't working when the starting is turning the engine. (b) the ECU/ECCS is responsible for operating the fuel pump, and (c) it (the ECU) is not doing so because it is not receiving the signal from the Crank position sensor to say the engine is turning (if it doesn't get a signal it turns off the pump as a safety measure).

This seems reasonable, but before forking out £150 for a new distributor unit wondered if I'd overlooked something more likely?

Thank you, Steve

Not sure when it operates, in the first 2 seconds or after, but there's a fuel pump relay that has been known to fail.

Thank you for the suggestion. Unfortunately the wiring diagram shows only one relay supplying the fuel pump and this is the operated by the ECU. Therefore if the initial 2 sec fuel priming occurs the relay has to be working. A shame, as a relay would have been a lot cheaper :)

Steve J, It sounds as if it is a spark problem. Have you checked the distributor to coil wire for resistance? I don't know the specific resistance but I am guessing in the greater 2k ohm less than 50k ohm range. Have you replaced the distributor cap and rotor? Weak spark will stop and engine from starting. Also check the coil and I think there may be a power transistor module on that vehicle. The module boosts the current that provides energy to the coil primary. Sparky

Hi. Thank you for the advice. I checked my coil windings with a ohmmeter and they were in the 25k range . I thought it might be somewhere else in the Distributor (which incorporates the coil, Camshaft Position Sensor, power transistor and capacitor) so obtained a secondhand replacement (£50) but that performed exactly the same, so at least I have a spare dizzy now!

I hadn't realised that the Ignition switch "start" position supplies a signal to the ECU to turn on the fuel pump at cracking speed and after testing that it seemed to be fine and the fuel pump worked. I'm sure it wasn't working on "start" beforehand so I may have a dodgy wire/connector on the Start circuit. Pump is working on start now anyway.

The engine still wouldn't start though so I pulled the spark plugs (again) and they were all very wet (again) so I replaced them and cranked the engine continuously with the accellerator pedal floored (standard technique for flooded carb engines but not recommended for vehicles with catalytic converters as it floods the converter with fuel) and after catching for a while the engine finally came up to speed and started! That was this morning. Since then it has started faultlessly on 8 separate occasions.

So...although I'm reasonably sure the fuel pump was not working in the start position originally it may actually have been flooded from the start. I don't know why. The only thing different to normal was that the car had been stood unstarted for 3 - 4 days. Prior to that it has always been driven daily and started perfectly. Having just spent 2 days checking wiring/ecu/Eccs and various sensor signals etc I'm a little peeved and have unfortunately lost some confidence in an otherwise excellent vehicle. I'm going to research this flooding issue some more and either fix it or at least be aware of the likelihood of it reoccurring after a few days standing idle.

I just hope I haven't toasted the cat !

Thanks again for taking time to respond and the helpful advice. Best wishes, Steve