NEED HELP!! Code 77

Hey guys,
I am starting to lose my mind and am hoping somebody may have some advice that can help.

I recently bought an '03 ZD30 GU, all factory, no mods at all.

a few days after I bought it, it started throwing engine lights with code 77, I had a reconditioned fuel pump put in under warranty. when I picked the car up, it started throwing engine lights with code 77......... back to the mechanic, another reconditioned fuel pump.

got the phone call that is was all ready to go, picked it up.... halfway home, code 77. I turned back around and took it straight back to the mechanic, his solution you ask??? another fuel pump!!!!!

so far, this patrol has had 3 reconditioned fuel pumps, numerous new filters (currently has a Nissan one installed), has had a new water sensor fitted for the bottom of the filter, fuel lines have been pressure tested to check for air leak, I have pulled out and checked the fuel pickup in the tank, the fuel tanks are both spotless and the fuel is crystal clear...................... still throws code 77.

It does seem to throw codes when the main tank gets between 3/4 and 1/2 or lower, don't seem to have much drama when the tank is full.

does anybody have any experience with this? is there something I am missing? I am about ready to either flick a lit match into the bloody thing....... or worse yet, trade it in for a Toyota!!!

any help would be appreciated..

cheers,

Quote:

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Originally Posted by colac pants man

It does seem to throw codes when the main tank gets between 3/4 and 1/2 or lower, don't seem to have much drama when the tank is full.
,

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I reckon your clue is there. Code 77 doesn't necessarily 100% mean it's a stuffed up fuel pump. It can be anything along those lines.

Here are few other threads for you to go through.

http://www.nissanpatrol.com.au/forum...ent-Power-Loss

http://www.patrol4x4.com/forum/3-lit...e-77-a-180010/

http://www.justanswer.co.uk/nissan/7...rol-fault.html

Some good info there dom. Nice work.

Update: drove down to cairns this morning, emptied the sub tank and almost full main tank, threw about 6 engine lights at me during the drive.

filled up before heading back up the range to Mareeba and didn't get a single engine light with both tanks full. I gave it a bit coming up the range to see if it would starve but went like a charm.

could there be something causing a vacuum in the tank setup that causes the FP to starve and throw fault codes?

I got the bits and pieces to do the spill line mod this morning, but not sure if this will even help...... cant hurt I guess

Quote:

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Originally Posted by colac pants man

Update: drove down to cairns this morning, emptied the sub tank and almost full main tank, threw about 6 engine lights at me during the drive.

filled up before heading back up the range to Mareeba and didn't get a single engine light with both tanks full. I gave it a bit coming up the range to see if it would starve but went like a charm.

could there be something causing a vacuum in the tank setup that causes the FP to starve and throw fault codes?

I got the bits and pieces to do the spill line mod this morning, but not sure if this will even help...... cant hurt I guess

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Yep. If you keep eliminating causes related to code 77, I reckon you'll get there eventually. It's a better approach IMO than throwing parts at it, particularly in modern diesel engines where the cost of spare parts can cost you your house. ;)

Is it a leak in the fuel line where it sits on the chassis near the wheel arch?

Fuel lines were pressure tested at the local diesel place, Will check again though

Quote:

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Originally Posted by colac pants man

Fuel lines were pressure tested at the local diesel place, Will check again though

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Pressure testing should ideally rule out any fuel leaks.

did the spill line mod, no joy, still throwing lights when the fuel gets down.

I work DIDO so car will have to wait for 9 days til I get back, then its getting a lift pump.

Quote:

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Originally Posted by colac pants man

did the spill line mod, no joy, still throwing lights when the fuel gets down.

I work DIDO so car will have to wait for 9 days til I get back, then its getting a lift pump.

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I've been wondering whether it has something to do with fuel level sensor(s).