Phase II "new style" Injector Conversion?
 

Is there a method to use Phase II injectors in our cars? I have a 93 VG that has what I presume to be a Phase 1 fuel rail and thus not drop-in compatible?

For reference - the left one (ignore the color) is Phase I, the style our vehicles came with, and they suck. The right one is a Phase II which is more reliable because the coils are isolated from the harsh ethanol'ed fuel.



https://cimg5.ibsrv.net/gimg/maxima....ca544d8e4e.jpg





I saw a few posts were someone alluded to perhaps doing so - namely DanNY here and James92SE (looks like he's gone inactive :() talked about it here. CS_AR discusses it a little bit here and mentions that Deachwerks has a Phase 2 conversion kit so I looked it up and it's about $170 which may or may not work with the maxima?. Is that the only (and therefore cheapest) route? I was kind of hoping there's an alternative fuel rail that's compatible with the 3rd gen?

For the 300Z I see they can:
I've replaced the injectors multiple times now and I've had my fill so being able to use the Phase II ones would be nice. By the way, until 2 recently electrically failed I've still been running the red-top VE injectors since like 2010 without any major issues except running a tad rich.

so you're looking at square connectors and oval/rounded connectors.
find a 94...it was either 93 or 94 when they swapped over the connectors and injector styles.

this is what i did for the VG..so YMMV...

i picked up the oval style connectors, the lower intake manifold where the injectors goes in, the injectors, and associated o rings and i was more or less good to go. i had to grind off a little meat from the upper intake manifold but aside from that it was good to go.

Well I think there's some confusion so let me just make sure we are on the same page.

By Phase 1 to Phase 2, I'm referring to change from the high mounted screens where gas flows directly over the coil (phase 1) to the low mounted screens where the coils are insulated completely from the gas (phase 2). The connector change from the square bracket to the oval top is unrelated (I thought) since they did in fact make oval top injectors that where phase 1 - which is what I have and what my car came with - we can call them phase 1.5 if that is less confusing. Here is what a Phase 1.5 injector looks like and it's what I currently have and what my car came with.

Phase 1.5 VE(red)/VG(pink) injector:
https://cimg6.ibsrv.net/gimg/maxima....9fd98c06e2.jpg
Notice that it has an oval top but the Phase 1 body/electrical design.

To my knowledge, Nissan never brought the Phase II injector body to the Maxima 3rd gen. Nearly every image on this board from someone doing an injector swap or discussing the top color paint dot etc all show pictures of the 1.5 style. So I'm not sure that a fuel rail, lower intake etc from another Max would work.

But you say that you did this and you do in fact have the Phase II body injectors??? I am SUPER confused. Are you sure it was from a donor Max and not a Z32? Was it a donor 94 SE (VE) to the VG? Can you enlighten?

Here's a photo of what I have for reference:

The left one is the one I _want_ to put in. The right one is what I pulled out.

https://cimg4.ibsrv.net/gimg/maxima....b9c844644c.jpg

Phase II is actually the injector that practically invented the idea of rice burners.

hmmmm...i see what you're saying.

TBH i don't remember what they look like. it's been years since they are in there. you'll have to do a little experiment and see what will work.

Deatschwerks makes a kit that allows a Phase II injector to work in a Phase I rail. I've been running the deatschwerk kit in my Q45 since 2010 without issue. Be sure to properly lubricate your o-rings when replacing injectors.

https://www.deatschwerks.com

Here's a picture of some Phase I Q45 (1991 model) rails with Phase II injectors where I used the Deatschwerks conversion kit back in 2010. I had the old rails and phase II caps nickle plated. Then I use a wiring harness from a Phase II car instead of using the wiring adapters. This is a common mod for Q45 and Z32 owners that want to upgrade to Phase II injectors.

http://i286.photobucket.com/albums/l...idesReady3.jpg

Here's the kit picture below

http://www.zshop.ca/parts/z32-deatsc...pter-kit-6cyl/

http://www.zshop.ca/wp-content/uploa...00zx-90-96.jpg

Hey CS_AR thanks for you addition. I saw your posts on the topic when I was searching - that nickel plated rail looks nice.

Can you help fill in any of these knowledge gaps:
.
Thanks for the help.

QUOTE=eventnick;9197148]Hey CS_AR thanks for you addition. I saw your posts on the topic when I was searching - that nickel plated rail looks nice.

Can you help fill in any of these knowledge gaps:
.

1. Did Nissan ever bring the P2 injectors to the 3rd Gen Max on any model? I see a few people/sources claiming they did but I don't think it's true. I think they're mixing up the 4th Gen Max. For an example (of many) if you go to Rock Auto and put in the 93 SOHC Max it lists some P2 injectors alongside P1s which I don't understand.

I'm no expert on 3rd gens, but for other Nissans it looks like P2 injectors started appearing in 1993. The 1994 Q45 used P2 where the 90-93 all used P1. Possibly the 94 3rd gen used the P2 injectors.

2. Are new P2 rails backwards-compatible with the P1 injectors? The above sources are making me think that perhaps I'm crazy and replaced P2 injectors with P1 injectors and didn't notice in the past.

I don't see how those could be mixed up. The electrical plug sockets are different. Also, the length is injector tips have different lengths.

3. What exactly is the physical incompatibility with the P2 injectors in P1 rail - flow constriction due to misalignment of fuel feed and injector screen? Or do they just not physically fit? If you look at my side by side above other than the screen location they are fairly similar with the O-rings in right places, same dimensions etc.

There is a machined circular tip that fills in the gap and allows the P2 injector to fit in a P1 rail. These tips come with an additional o-ring.

4. Do you know of anyone who has successfully done the conversion with a VG30E? I'm concerned about the clearance of the injector on Cylinder #2 with the upper plenum if they do sit substantially higher with the rail adapter kit.

I don't know. If you use the kit, the rail will sit in the rail cup. The rail will mount using the correct rail mounting spacers. I know on a Q45, if you use P2 rails, the mounting spacers require modification. There are some slight differences in the insulator "donut" that mount into the lower intake manifold. I didn't want to go through trying to make the mods for a P2 rail fit into P1 runners on the VH45DE, so I went with the kit. It seemed like less headaches and it worked well.

5. The Deatschwerks kits is a bit premium ($$$) - I've seen some other kits that are a bit cheaper - do you have any thoughts on those? I presume that any kit that fits a Z rail will fit any VG30e or VE rail?

No idea about the other kits, I do know that DW sent mine off to be plated with anodized aluminum. I knew I would be keeping the car for over 10 years and didn't want to go back under the intake plenum ever again. Its a two day job to pull the injectors on a VH45DE -- not fun.

The P1 to P2 adapters for a will work for any Nissan model that is running P1 injectors. There are a lot of 240sx and 300zx owners that have changed over to P2 injectors.

Thanks for the help.[/QUOTE]

Here's a picture of a P2 injector with the DW adapter on the tip.

https://cimg3.ibsrv.net/gimg/maxima....0f1ad0c355.jpg

Just to clarify, the injectors in the picture above are interchangeable. I've seen people with early 4th gens replace the injector on the RIGHT with the injector on the LEFT.

Here's a picture of the inside of a P1 rail. There is plenty of room for fuel to enter the P2 type screen using the adapter.

http://i286.photobucket.com/albums/l...8/RailPic4.jpg

The Phase 1 injector on the left is a ROTARY style injector where the injector on the RIGHT uses a plastic PINTLE cap and o-ring. O-rings are missing from the P2 injector in the right.

without using the DW adapters???

Correct. The DW adapter allows P2 injectors to work in P1 rails. If the injector has the little plastic pintile cap at the end with the lower o-ring, it is a P2 injector.

https://i286.photobucket.com/albums/...psievm1hn1.jpg

When I checked Rock Auto, it shows either type of injector screen for a 93 with DOHC - red tops. If you current injector above is on the right, you can use P2 injectors (pintle caps) without modification. You have a P2 rail. I don't think you need a DW kit if this is what you want to do.

Well I can confirm the P2 injectors are interchangeable with the P1.5 injectors. No modifications necessary.

I wonder why all this time we haven't been pushing 93/94 owners to get the P2 injectors for replacements over the P1.5s that suck ***.

Thank you for your help CS.

Here is my secret to pulling these injectors with ease:

https://www.harborfreight.com/push-p...ers-63700.html

https://cimg8.ibsrv.net/gimg/maxima....7701223e61.jpg

I upgraded my 1990 Maxima to the 93-94 fuel injectors and harness several years ago and I've upgraded every connector to the weather pack style from the MAF sensor, TPS, Water temp sensor, etc... all these connector pigtails are available on eBay....that 1984-91 wiring was suspect to extreme seal deterioration and excessive terminal corrosion. Upgrading to late model weather pack connectors are the best and the 4th gen Maxima fuel injectors connectors are identical!

If I'm not mistaken when I upgraded my injectors a couple years back they came in the p2 style with the screens on the bottom. I had the set complete with the rail that ran flawlessly but sold it some time back I believe with the headers I had. If you have a 93-94 then you didnt have to update the plate below the intake manifold but if you were going from 89-92 to the 93, 94 injectors you had to change the plate below the manifold. I dont recall if the rail needed to be changed aswell to accomodate the newer injectors or not but if memory serves me right I think it did.

Just Fyi the later 93/94 VG connector are the same as the VQ30DE found in the 95-99 Maxima(s)....I would suggest everyone throw those old school rear bulb seal type connectors in the trash and upgrade all your sensor's connectors to the weather pack style which are the modern day modular sealed plugs...eBay has alot of this and later Nissans do as well that are in your local boneyard. Just search for the plug type you need and The boneyards are full of them.

So I have a bit of a update/problem. Car wouldn't crank. Thought a bearing had seized but after being able to turn the crank shaft with a pry bar the mystery remained. Long story short - I determined the engine was hydrolocking. Tore it down and cylinder 1 had lost it's pintle cap and the oring was half hanging out. In fact upon closer inspection - ALL the pintle caps were sticking out way too far - half of them I was able to take of with just a light twist of two fingers.

https://cimg2.ibsrv.net/gimg/maxima....32e594ca48.jpg
Right - What it's supposed to look like. Middle and Left sticking out so far the drip legs on the pintle caps aren't even touching the pintle area anymore



So I thought it was just bad luck with a faulty pintle caps but then I pulled all six and looked at them. Can you spot the problem (I think)?

https://cimg0.ibsrv.net/gimg/maxima....9181db76f9.jpg
Ignore the diff color pintle caps. I swapped one before I noticed what could have been wrong.

Don't see it? Here's them next to a different phase 2 injector that I have.

https://cimg2.ibsrv.net/gimg/maxima....9d0be3a67b.jpg
The spacer and oring on the left 2 are humongous.


Here's a comparison (of many similiar ones) as offered by CS Performance on Ebay:

https://cimg3.ibsrv.net/gimg/maxima....5e47f9211f.jpg
Smaller spacer, smaller oring. Can actually see some of the injector body between the pintle cap and the oring.


It's my guess that the oversized oring/spacer is slowly pushing the pintle caps off which then leads to the oring slipping past and leaking fuel. I suppose it could also be weak Chinesium pintle caps. I guess this is a cautionary tale on taking your chances on ebay garbage from china - really have to double check everything but in my case it wasn't so easy because I was coming from the Phase 1.5 injectors which are very different looking and indeed have kinda fat orings so I didn't have a great reference.

When I was searching I noticed several people having a similar problem in the 4th gen forum - broken/missing pintle cap leads to oring slipping leads to flooded engine. I wonder if those people were on factory injectors or aftermarket reconditioned ones. CS_AR, I know you've dealt with these a lot - I noticed a few of my filter baskets were pretty loose after I took them out even after I verified they were snapped on to where they are supposed to be. Have you noticed this issue when rehabing injectors? I guess it's not a big deal since the fuel rail will hold them mostly in place.

Why did Nissan decide that the lower oring should use the pintle cap to press on instead of some sort of rigid lip on the bottom opening of the fuel rail? Boggles the mind.

I'm not sure what I'm going to do at this point - getting a set of lower OEM orings, new pintle caps, and scrounging some used properly sized spacers is probably going to exceed $50 after shipping. Meanwhile it looks like I can get a complete set of six flow matched, lifetime warrantied, properly kitted Red Tops from CS Performance for like $120. (For some reason the 'correct' colored tops for these are like $300 for a matched set). Or I can just get a set of 6 random 'correct' colored tops for $15 a pop also with a lifetime warranty. Seems a shame to throw away otherwise perfectly good injectors given these things used to be worth $100+ each but the economics has changed so much.

The injectors in these cars are the bane of my existence.