2006 GU Starting problems

[Pilly]

My 2006 GU has recently started behaving badly on start up. At times the vehicle will not fire eventually flattening the battery. At other times an instant start up. At other times 3 or 4 turns of the ignition / cranking the engine and then firing as if nothing wrong. In last week replaced starter motor, new fuel filter, new fuel, new battery - car otherwise in excellent condition. Once running performs like a new vehicle - no smoke, plenty of acceleration, smooth acceleration ,etc. This issue occurs whether hot or cold.

Mr Nisan suggested replacing the injection pump due to potential electronic faults - Diagnostic had a big "think" attached to it.

Any advice would be greatly appreciated

Thanks

Pilly

[Col.T]

G'day Pilly and welcome to the nut house
I'm sure you'll get some more/better answers but here's my thoughts.
If it runs sweet once it's started I'd be looking for something solely to do with starting.
Shouldn't be the starter motor 'cause that's usually obvious, she just don't turn.
Shouldn't be the fuel filter or fuel 'cause they'd have an effect once it's running if starts are so crap.
Shouldn't be the battery 'cause if it busts it's ring off trying over a long period it PROBABLY was OK. If clapped they don't work for long on diesels.
Injection pump sounds odd as I'd have thought a stuffed pump would show something in running.
Starting in really cold weather is sometimes harder and I've found that sometimes turning the ignition on/off/on a couple of times and therefore lighting up the glow plugs more than once has on occasion helped. Dunno if that's totally good though. Perhaps someone else will shoot that one down. (When you say it happens hot or cold, do you mean weather on engine temp?)
Reckon I'd go for a check up on the glow plugs although I've never had a prob. over 20 years and two models OR chase up any error codes mainly as I can't think of much else.
Computer codes totally suck and if you aren't getting that warning dash light, I'd say there's probably nothing electronically to be warned about.
Try to wait for a better answer here before you get sucked into uncounted trips to the dealer to read the codes and fix something maybe.
Good luck mate
Col

[nissannewby]

What drive train do you have in your patrol?

[Pilly]

G'day Pilly and welcome to the nut house
I'm sure you'll get some more/better answers but here's my thoughts.
If it runs sweet once it's started I'd be looking for something solely to do with starting.
Shouldn't be the starter motor 'cause that's usually obvious, she just don't turn.
Shouldn't be the fuel filter or fuel 'cause they'd have an effect once it's running if starts are so crap.
Shouldn't be the battery 'cause if it busts it's ring off trying over a long period it PROBABLY was OK. If clapped they don't work for long on diesels.
Injection pump sounds odd as I'd have thought a stuffed pump would show something in running.
Starting in really cold weather is sometimes harder and I've found that sometimes turning the ignition on/off/on a couple of times and therefore lighting up the glow plugs more than once has on occasion helped. Dunno if that's totally good though. Perhaps someone else will shoot that one down. (When you say it happens hot or cold, do you mean weather on engine temp?)
Reckon I'd go for a check up on the glow plugs although I've never had a prob. over 20 years and two models OR chase up any error codes mainly as I can't think of much else.
Computer codes totally suck and if you aren't getting that warning dash light, I'd say there's probably nothing electronically to be warned about.
Try to wait for a better answer here before you get sucked into uncounted trips to the dealer to read the codes and fix something maybe.
Good luck mate
Col

I had 3 of these vehicles and experienced nothing like this. All your points sound logical and hence currently looking at cam sensor....

[Col.T]

Pilly,
funny thing that. Only prob I've had that showed up as a warning light issue was the cam. position sensor. Engine though started OK and ran as good as ever. I think there's a crank position sensor (maybe) that takes over if it has to. The manual isn't clear on replacing it and being unable to read the diagnostic codes myself I ended up getting Mr Nissan to replace it. You can do it yourself though and if you confirm thats your trouble, get back to me and I'll put you on track if you want to have a go.
All the best
Col

[Pilly]

Thanks Col, latest diagnostic (at great expense to mgt) is faulty brand new starter motor, drawing excessive current and sending the ECU off chasing false fault codes impacting on the signals necessary to sync the pump. So long story short dropping in another new NISSAN SMtr and we'll see how that goes. Auto electrician and Fuel Injection "expert" are sort of agreed around this solution - Hey I'm only paying for it. What about the MAF - I reckon if this was playing up I'd experience performance issues as well but others have suggested cleaning it to help with starting????

Rgds Pilly

[threedogs]

when cleaning the MAF disconnect the battery for 1/2hr or so.
May want to fit a catch can to stop the MAF from getting dirty
Just be sure MAF is dry on re installation,
Big job changing Crank pos sensor.

[Pilly]

All,

Starting issue gone away after removing major short affecting starter motor current draw - At least it wasn't a $4K + fix quoted by Mr Nissan.................. Thanks for all the advice.

Rgds Pilly

[threedogs]

Good result ,I had my CPS replaced after Alternator packed it in.
But my symptoms were limp mode all the time. Shite of a job changing it BTW