ZD30 Rough Idle After Fuel Filter Replacement

[LR Disco 2]

Good day guys. I recently serviced my 2004 Nissan Hardbody 3.0 16V Td and replaced the fuel filter + sedimentor. I also replaced all fuel hoses and clamps with new ones as they were looking tired and somewhat perished.
I've done this many times in the past and its never given me issues. I primed the filter as usual. I noticed it wasn't getting harder and the bakkie didn't want to start. So I disconnected the hose that sits between the filter and injector pump, primed it and saw that diesel was indeed coming out. I then reconnected the hose and then primed it. It hardened and all was well. I then started her up and now its got such a rough idle. I let it idle for a long time... even up to operating temperature and it hasn't changed at all. I took it for a drive in hopes that any air bubbles would just pass through. No difference.

I disconnected the hose from the fuel filter and the sedimentor. Primed a little more. Reconnected the hoses. Primed it again and it stiffened up once again. I started the bakkie no problem. The idle is still rough and constantly feels like its going to stall.

I then read somewhere that you should disconnect the battery and have the ECU reset itself. I thought it was worth a try. Didn't help at all.

This is 2 days in the making and I've got no idea what to do. I don't want to drive the thing because I'm worried it leaves me on the side of the road. Like I said, I've done this many times and I've never had issues...

Any theories, suggestions, help would be much appreciated!

[jelo]

Sounds like some sediment went down the pipe to one of the injectors.

[NewLandy]

Is there a chance that the hoses/clamps are not sealing properly or maybe you got the fuel/feed/return lines the wrong way around (not sure if this is relevant here)?

[LR Disco 2]

Is there a chance that the hoses/clamps are not sealing properly or maybe you got the fuel/feed/return lines the wrong way around (not sure if this is relevant here)?

I thought so too. I checked everywhere multiple times and everything looks perfect. I went over everything with a fine tooth comb, and its exactly the way it should be. All clamps are tightened, filters are tight but not overtightened, no lines mixed. Its exactly as it should be.

[LR Disco 2]

Sounds like some sediment went down the pipe to one of the injectors.

How do you check for that or what should I do to sort that out?

[jelo]

How do you check for that or what should I do to sort that out?

I wouldn't even try to sort that out in a home workshop.

You're a little screwed until the workshops open in the new year.

The only option is to try add some injection system cleaner to the fuel tank and take it for a drive.

[LR Disco 2]

I wouldn't even try to sort that out in a home workshop.

You're a little screwed until the workshops open in the new year.

The only option is to try add some injection system cleaner to the fuel tank and take it for a drive.

Right, I'll give that a shot after Christmas and let you know how it goes. For the meantime, I won't be moving that bakkie anywhere.

[jelo]

And now you do understand why Murphy waits for precisely this time of the year to do his best work.

[LR Disco 2]

And now you do understand why Murphy waits for precisely this time of the year to do his best work.

Well said!

[LR Disco 2]

Gents, it was just air in the fuel system. Specifically trapped air by the fuel pipes going into the injectors. It's never happened to me before, thus being so confused as to what was wrong. I ended up loosening the size 17 nut by the injectors a little. Had the air leave the system, fastened the nut again, and it already improved drastically. I then let it idle a bit and took it for a 20km drive; slow, normal and fast driving and now its perfect.

I'm glad I've learnt something new... I do however feel very stupid for not using my common sense. Maar, so leer ons...

[4ePajero]

And now you do understand why Murphy waits for precisely this time of the year to do his best work.

Murphy was an optimist - things get much worse than he ever imagined.

[4ePajero]

Gents, it was just air in the fuel system. Specifically trapped air by the fuel pipes going into the injectors. It's never happened to me before, thus being so confused as to what was wrong. I ended up loosening the size 17 nut by the injectors a little. Had the air leave the system, fastened the nut again, and it already improved drastically. I then let it idle a bit and took it for a 20km drive; slow, normal and fast driving and now its perfect.

I'm glad I've learnt something new... I do however feel very stupid for not using my common sense. Maar, so leer ons...

Glad you got it sorted - I was starting to fear a damaged injector (air can do that).

[jelo]

Murphy was an optimist - things get much worse than he ever imagined.

I think a Christmas Elf helped LR Disco 2 this time round.