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Has anyone replaced their HPFP on their N55? I am getting occasional 3-4 second long cranks, but only when the car sits in the sun. I found DIYs for the N54, but do not see any for the N55. Has anyone done this? Is it similar to the N54? Harder or easier?

[LoneWolfPistol]

Yes, I have. And it is similar to N54

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Originally Posted by Simplev33

Yes, I have. And it is similar to N54

What were the main differences, beyond the DME being attached to the intake manifold?

[bbnks2]

Originally Posted by Welcome to NBA Jam

What were the main differences, beyond the DME being attached to the intake manifold?

NEWTIS will guide you through everything...

[lwgrenier]

I've replaced mine. You don't have to remove the intake manifold. Just remove air box, charge pipe, throttle body, all hoses and wires, and you have easy access to the pump. Took me about 3 hours to replace mine. Only annoying part is getting the bolt on the crankcase side of the pump out. You'll need a long 5mm (I think) hex head socket extension or allen wrench if you're not super concerned with torque tightening values.

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Originally Posted by lwgrenier

I've replaced mine. You don't have to remove the intake manifold. Just remove air box, charge pipe, throttle body, all hoses and wires, and you have easy access to the pump. Took me about 3 hours to replace mine. Only annoying part is getting the bolt on the crankcase side of the pump out. You'll need a long 5mm (I think) hex head socket extension or allen wrench if you're not super concerned with torque tightening values.

Awesome, great to know. Thank you. I was prepared to remove the manifold. I'm going to get a few sizes of Allen key sockets. That seems to be the most annoying bit.

[cahme]

I'd remove the intake. It shouldn't add more than 20 min, most is figuring out how to disconnect the DME connectors, but it will allow you to clearly see what you are doing with the HPFP. This should help

If you have a Harbor Freight in your area, buy a set of these, or find something similar (5" hex). You will need it, or have to get creative. You don't need the ball head, but it may come in handy later (dv+)
https://m.harborfreight.com/7-Pc-38-...Set-67888.html

I've replaced my HPFP twice. The first it just went out with no warning; misfires and ignition shutdown on several cylinders. 40k mi later, I had long cranks after sitting overnight some times. I got my first reman from FCP, so that second was refunded and I've been fine since.

[weehe126]

Yeah when I replaced mine I took the IM off. Made it way easier.

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I read that the final two DME connectors on the left (5 & 6) use the exact same size connectors, and you can destroy your DME if you accidentally swap them. Additionally, I read a rumor that you can plug them in upside-down. If that's true, I'm really surprised by a design like that.

If I do remove the manifold, I plan on marking both the direction and number on all connectors and on the DME with a silver marker.

[weehe126]

Idk where you read that. The DME connections are straightforward and I'm pretty sure you can't mix connections up. Definitely cant connect upside down.

[lwgrenier]

I don't know if it makes a difference that I'm AWD (no oil cooler?) but I had plenty of space without removing the IM. I did have to remove it one time and the connectors for the DME were a huge pain. Maybe just because they had never been disconnected before but they were very brittle and rigid. The clips for the connections will also snap shut even if they aren't properly seated so I ended up turning on my car with some connections still not connected. I was lucky but that could've done some serious damage.

[Pladi]

The DME connectors for the N55 are kind of a pain in the ass to remove. Easy to put back. Especially if you dont take off the intake manifold.