The Nissan Path

Anyone have suggestions on getting the screws loose that hold the metal caps over the fuel injectors?

I have no idea why those aren't bolt heads instead of phillips but they are stuck dang good. I am hoping to avoid the dremel solution but WD-40 and brute force don't seem to be cutting it.

Managed to get those screws loose with a bit of hammer work.

Although on some of the caps I was only able to get one side loose so I figured that I'd rotate the whole cap in order to loosen the screw. It worked but busted the crap out of the injectors.

Good thing the goal was to replace them. But so much for getting my core charges back.

Now I just have to figure out what the difference is between the brands available so that I can determine which kind to buy. Anyone have any experience good or bad with particular brands that they could share?

As far as the injector cap retaining screws, I use an impact driver w/ a Phillips bit and carefully (since the base is aluminum) tap them loose.

You don't mention what year or engine you have, so I'll assume it's a VG30E since that's the most common engine for WD21 Pathfinders. Nissan used paint dots on the fuel injectors to identify them. If you are replacing less than six, than you are supposed to match the paint dot to get the correct injector; the paint dot identifies the spray pattern of the fuel injector. If you are replacing the whole set of injectors, then it doesn't really matter about the paint dot since you will be buying six of the same. It sounds like by your post you are replacing the full set of six.

My first bit of advice: be careful if you are looking for parts on Ebay! There are a lot of counterfeit injectors (among other auto parts) that look and are often sold as "OEM" fuel injectors. If the part cost is too good to be true, that's a good sign that "something's up." Another tip: make sure you lube the "O" rings before you install the fuel injector. A dab of clean motor oil will work, but I prefer to lube them with Vaseline (petroleum jelly).

Genuine Nissan injectors are expensive, at least the last time I checked. They are made by Hitachi. You can get Hitachi fuel injectors for around $50 each. On my 2003 Frontier (VG33ER engine), I installed a set of Autoline remanufactured fuel injectors 3-years ago and they've been fine. I got them using a 30% discount code at Advanced Auto Parts, ordering online (shipped to home) and returned the cores to the local store, which saved me shipping them back. I think I spend about $100 for the set, back then. Rockauto sells Autoline for $34 including the core, so, if you don't send back the cores, it's still a less expensive option AND they have a 2-year warranty (which is double that of the Hitachis). They also have AUS injectors for $25 on closeout; I've used AUS before and didn't experience any problems, but the warranty is only 90-days and my experience with Rockauto is that a many of their closeout items they sell is "old stock."

So I wasn't lucky enough to get all the cap screws out cleanly. Chewed the mess out of a handful of the heads getting them out.

The replacement screws from Nissan are a few days out an expensive. Do you think I can just use stainless steel hex caps from the local hardware store? Or do I need to make sure what I use is grade 8 hardware or something of that sort?

Also, anyone have opinions on whether spring washers should be replaced on nuts and bolts along the way? General 'good practice' would tell you to replace them, but I'm not convinced whether it really matters; especially when the torque values compress them down to flat washers anyway.

You can use bolts from the local hardware store if you can find the correct thread and pitch. 4mm x 0.7 comes to mind, but it's been a long time since I had to buy any and my memory could fail me. I would put some threadlocker on them. If by springs you are referring to the rubber insulators that go between the top of the injector and the cap, I've done it both ways (re-using them and replacing them with new) and didn't have any problems either way. When I did the full set of injectors on my 03 Frontier three years ago, it had 185,000 miles on it, so I replaced them along with the seals under the injector rails and the fuel pressure regulator.

By spring washers, I was referring to the metal washers that have the little break in them that is offset when they are new but gets crushed flat when you tighten things down.

Those types of washers are on the screws on the injector caps, but I was also asking more generally because every bolt and nut on the engine seems to have one of those washers under it.

Oh, ok. I just re-use them.