Sunday, Nov 19, 2017 at 15:46
Hey Rmd
I'll have a crack at trying to relay the info given to me by my diesel mechanic in
Cairns. I do as much work on vehicles myself, but if it's too much for me... it goes to him LOL
I drove around in my zd30 Navara for around 3 or 4 weeks with 4th gear badly surging or as some people say 'hunting'. It was almost non operational. After 2 weeks I did my research and it pointed to a neutral switch so I purchased and replaced. Easy peesy... problem fixed.
2 weeks after new neutral switch injector pump died (Bosch vp44 pump... google it). The only fault code the thing threw up was 0073 which is 'pump communication line' which is the plug & elec line from ECU to pump. Myself and a mate did everything we could to try and start the vehicle to no result. My mechanic stressed that the vp44 does inherently die for no reason from time to time BUT there is nearly always a trigger for it and his first question was have you had any issues of late, which i responded with the 4th gear hunting & neutral switch. Bingo he said.
His take on it was that Id been driving on it for a matter of weeks it had upset a portion of the ECU thus causing wrong injection... not so much the pump itself but injection in general was not fluent as per normal. Again and as you say the pump just gives pressure, but the injectors were being disrupted by the surging. It all seemed pretty likely to me in his words.
My further research revealed the Vp44 normally throws up a code 0076 'spill valve' when it is dead. In my case the 0073 comm line is extremely common in the 3L Patrol, same but intercooled. It is mostly due to air induction into pump e.g. running out of fuel, air in lines. 0073 is a code that can pop up from time to time in the Navara's being caused by running severly low on fuel e.g. starving injector pump, or problems associated with ECU (as per my case). The ECU from memory can nearly always be reset for minor issues by starting vehicle and letting run for 10mins straight however injector pump can never be reset. It must be replaced.
Id like to think I've not been sold for a dummy. IfI have been it must have been Johnathon Thurston kind of dummy!!!!
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