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Have u rewired the fuel pump? They run low voltage at low load and that may be causing u grief. Even if u just re earth the negative wire to remove the variable voltge.

There is a diy on rewiring the fuel pump

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Haha yeah it's getting to the bonfire level. Ok so I dodgy rewired the earth with some 3mm from super cheap and the hesistation is gone at 2k. Will wait till the morning to see how it starts. Idle still hunts around 100rpm and has got a slight miss so could be fpr still? Tps set to 0.4v at idle and 4 at wot

Looks like it finally. Will see how it starts in the morning. Still hunting and running a bit rough at idle but it seems to settle occasionally with the a/c off. Also the surging is still there. On the first few pulls when it's cold it has absolutely nothing until it hits boost then it hits it hard. After the first 2 or so pulls its fine. Nice gentle transitions to boost.

Ok so cold start issue is still there not as bad though just cranks for a while then fires once or twice and stalls then if I hold it on start and crank it through the first few cylinders it's ok

It sounds a bit like you have leaking injectors so when you leave it over night they leak a bit into the combustion chamber so when you start it, it take a while to clear the excess fuel then idle up or it could just be the Nissan computers they are pretty shit in stock form. My suggestion get a computer with out need of the afm so that cuts out one problem. You said at the start that it may have 550cc injectors they wont run very well with stock ECU. The standard CAS are made mitsubishi as well so it probley hasnt been changed so that might be something else to try and change.

Yeah I found one of my injector top o-rings was split so I resealed them all. Could be a possibility of a dribbling injector but it's holding fuel pressure not certain how much will have to test over night to see drop rate. But could be. And their not 550cc looks top be standard red tops p.o. Bullshitted me. And yeah when I get back to Townsville I'm going to plug in a consult and check timing when it's doing it

I Think the pressure drops off pretty quick with no fuel pump behind it. I've replaced lines where theres been no pressure only lines full of fuel after about 2 mins of waiting. More then likely it will have an orifice in the FPR that doesnt really make a difference when it has a fuel pump constantly supplying pressure, but when you turn the car off lets all the fuel drain within a minute or two.

Could be wrong but thats how I would expect it to work

The only real way to know for sure if your injectors are a bit dodgy is to pull them out and have them checked and flow tested to see if there still spraying 100%. I dont think the above theory about them leaking over night will prove to be right, but it could be causing problems if you have a lazy injector.

Well afaik it's supposed to keep some head pressure as the fuel filter has a check valve to keep prime there. And yeah I don't think injectors are to fault as fuel consumption is normal and wot + high load pulls are fine. But I will look at testing them or replacing them when I get back to townsville

Sounds like we are in the same boat. I only hard wired it because I developed a sputter at 2k. Have u checked tps?

No luck stalls when started if acceleration pedal not pressed. When I go for a second start, it starts but struggles and slowly builds up revs. will video it one day...

Tps voltage at 0.48 looks fine.

Yeah sounds like same issue. Could be separate fault though. Tps should be 0.4v to 4v at WOT according to manual. But that's not that far off. What about o2 sensor? Cleaned/resoldered pins on the afm? Checked for boost leaks?

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