Good info on trying to rebuild the HPFP! I'm sure I will try the o-ring swap at some point with my '07 MCS N14.

Additional info.
Don't forget to change the in-tank fuel filter too. If you are over 75k mi and have a heavy foot, you would probably benefit from a change out. You might dismiss this thinking that you are getting 90-100 psi low side pressure, but if you are not flowing enough fuel to the engine, then you will get a power drop in the higher RPM and high-load side of things. This will be exhibited even if you change the pump.
Note... when you do change the filter, make sure to lube the o-rings associated with it, before reassembly. If you jank up the large o-ring that seals the filter housing halves, you will get HPFP failure symptoms. Trust me on that.

EDIT: Doesn't the N18 use a bosch pump, where the N14 uses the continental? This rebuild wouldn't apply, correct?

 

I'm ahead of you on this but it's good to get the validation. I bought the car at 143K and it was clear that owner #2 hadn't maintained it for squat (as I type this, I'm getting the front crank seal replaced, and guess what else needs replacing? The harmonic balancer/crank pulley -- it's visibly a wreck). So several months back, before getting into HPFP swaps, I replaced both the in-tank fuel filter *and* the LPFP. Both have been in place long enough that I can say with absolute certainty that (1) old and new behave identically and (2) they either were not the problem or both old and new are broken the same way.

I really appreciate that input though. I thought I was maybe engaging overkill by digging through the low pressure side -- sounds like I was on point.

Depends on the date of manufacture, apparently. My N18 is an early-manufacture N18, from what I gather. So I have the Continental N18 pump. In getting my first replacement HPFP I went through all manner of confusion because of the two different Continental flavors of HPFP (N18 and N14) and the Bosch HPFP (N18). But mine is the N18 flavor of the Continental, no question.

Cool that this info is helpful to people. I'm still somewhat in headdesking mode as I hit snags here and there, but I'm sure getting to understand the nuances of all the electromechanical behavior from HPFP to HPFP... that much is wicked interesting!

 

Yep, after looking, it seems it's a 3/12 cut-over date. I didn't realize they went that long into the N18 run before changing over to the Bosch. Now if only we could retrofit. I read in another thread that they don't have the same connector and the signal on that plug is different too. Can't remember specifics at the moment.

 

I would give a tooth or two or three to have a way to pull off a retrofit!

 

it looks mechanically they should retrofit, but there is an adapter that mounts to the head that i can't find a part number for:




Apart from the mechanical differences, would only need to figure out the electrical connector... They both appear to be two-wires, but the physical connector shape is different.

 

You are correct. If the car was originally equipped with an N18, then, in theory, you could do the swap, change the plug and tell the ECU (somehow) that it uses the new pump. Telling the ECU to change it's input values is the trick. I want to say what I read was from where Tigger2011 was trying to do just this a while back (few years ago). Something about the two pumps report something differently via the plug.
EDIT: I think the cam slots are different too. [I really would like to find that thread] So, even if you do the right angle adapter, it may not work.

Update: I found the thread. It starts on page 4 and continues on. In short, lots of stuff changed for the bosch pump.
More info:

 

Yeah, sounds like a retrofit is iffy business at best (and that would be optimistic). Unfortunately.

So I found out today that my original HPFP is not in fact the original HPFP -- It's an HPFP put in in 2013 after the original HPFP failed.

So I have a 2013 HPFP and a junker HPFP of unknown vintage. The former is the one I put Viton rings on and the latter is the one I have fluorosilicone rings in. The latter "behaves better" but is still a bit wonky in some ways it was before tweaking, and even pre-tweaking it behaved better than the 2013 HPFP (which was in sorry shape before partial refurb, period). A very curious new behavior: when it (the one with fluorosilicone rings) parks in the 80PSI basement at startup, turn the car off and start it again and it often goes to normal pressure range immediately. I'm not going to spend a lot of time digging into the whys of it, as it still shouldn't require any sort of 2-step dance maneuver; but it is certainly interesting.

Still very interested in detailed technical commentary, especially about the thermal compensator and any other ideas about what might be going on inside the fuel supply/pressure solenoid.

 

Simply remove the fuel pump fuse, crank the engine till it stalls, and you have everything depressurized.

Just a side note, but when I had my fuel pump replaced under warranty after it was failing there was a note saying that they checked the oil and found that it was out of oil.... I can find the original notes and report back with the specific verbiage.

My bet is that as soon as the computer detects any unexpected dip in pressure it shuts down / activates limp mode the HPFP causing the 80 PSI reading. This will continue until a reset.

Added to my to-do list.

 

Yep. That's exactly how I do it. Interestingly, my Mini seems to not want to give up this fight, so I do the crank/stall at least twice, usually 3x, and then I let the car sit for at least an hour. At that point when I remove the fuel lines from the HPFP I can't even get a fuel drip unless I orient the hoses just-so (usually while physically removing the HPFP proper or trying to get at its electrical connector).

I am VERY interested in this. Of the three HPFPs I have had on the car, 2 show no leaks but misbehave in different degrees of "problem HPFP" fashion even post-o-ring-replacement. I suspect they are out of oil or have less oil than they should have. The third HPFP is an OSIAS "new" pump (made in China, manufacturer worthless for warranty) and developed an oil leak in under 400 miles. Some pics:




Note ring of oil on bell housing of thermal compensator. This is not engine oil; it is of different consistency and viscosity and is not dirty at all.



Another view of oil collecting on bell housing of thermal compensator. Not engine oil, of different consistency and viscosity and is not dirty at all.



View of HPFP oil collected in the bleed screw of the thermostat housing, which sits immediately below the HPFP when installed. Note: this is a brand new thermostat housing, installed in December along with replacement of all coolant hoses. The housing and all hoses below the HPFP were covered in an oil sheen from the HPFP leak.

Yep. I've also noted a related behavior. If you can get the HPFP up to proper PSI range *immediately* after starting the car -- which in my case, seems to mean rev it up to *above* 4000RPM and hold it there -- while the computer is doing all its cross checks it will note the higher reading and clear the half-engine light leftover from the prior run (and along with it, limp mode from the prior run). However, if the HPFP is truly having trouble, you're going to feel it (the engine will stumble, etc.) and you won't be able to pull this off until the HPFP has stabilized (meaning, in my case, warmup by whatever definition).

Some new notes, minor stuff, but helpful to have the progression over time.

(1) The fluorosilicone rings are definitely a win, at least in the context of an HPFP that might well be out of oil (or have insufficient oil) and that needs to do a better job of warming up fast. I can get my HPFP up to speed in 5 minutes or less, and once it has decided it is "happy" subsequent starts tend to immediately go to normal PSI so long as the car has not been sitting for too long. For example: I can stop the engine to fill the car up with gas, fill the tank, then start the engine; the HPFP comes right back.

(2) The rings are not the full solution. I still see the occasional dip below 620-ish PSI. How long these dips last and/or how close together they are seems to govern whether a CC-ID 029 (half engine light) is thrown as well as whether that results in going into limp mode (increasingly not so much).

(3) The trigger for the dips seems to correlate with the car being in too high a gear to "be pushed" given the amount of fuel the engine is getting; dropping into a lower gear the moment I feel any unevenness from the engine seems to preempt the problem. For folks with automatic transmissions, I have an auto, so this minor workaround is not limited to those with a stick shift. Sport mode in auto tends to keep the thing revving higher as well and doesn't get me into low-torque situations that trip up the HPFP... as much.

(4) None of these optimization-ish tips will apply, in my view, to an HPFP that is just plain uncooperative even with new o-rings. My 2013 HPFP with the Viton rings was not nearly as easy to manage, whether pre- or post- Viton ring replacement. But I do not know how my 2013 HPFP will behave with fluorosilicone rings.

(5) I am wondering whether rings of a slightly larger wall diameter -- maybe another 1/64th of an inch -- would be helpful. I'm intuiting that if the fluorosilicone rings were more firmly seated, their warmup wouldn't matter as much. But it is difficult to peel this question off from whatever is going on with oil in the HPFP, and I am not sure that I can get rings of a different wall diameter (WD) but the same inside diameter (ID).

I find it interesting that the computer isn't hair-trigger about going to limp mode, and that it does seem to have situations where it will take it out of limp mode mid-ride. Pretty nuanced; but not necessarily easily intuited.

Let me know what you find out about the oil. Also, any idea what kind of oil one might hypothetically put in the HPFP, since the OP of this thread has been quiet on the subject?

 

No idea on what kind of oil. You could send a sample to blackstone laboratories and see if they can ID it. Contact them of course and see if that is possible.

One possibility is that the rings and just ever slightly too small. Once heated up the expand and get a proper seal.

 

I'm not familiar with Blackstone but I'll start digging. Thanks for that. HPFP 3 is definitely supplying plenty of oil to work with for testing... oy.

Yeah, what you said about the rings. I'll go see if McMaster-Carr has a fluorosilicone o-ring product that is slightly "thicker."

 

https://www.blackstone-labs.com/

Also great for getting info on your engine oil.

 

Jackpot.

McMaster-Carr part number 8333T168 for the top (smallest) ring "Chemical-Resistant Low-Temperature Fluorosilicone," $6.33 for a 5-pack; 8333T169 for the mid-shaft ring at $6.90 for a 5-pack. 0.103" wall diameter (WD) instead of 0.070" wall diameter.

Stay tuned, should have these in a matter of days. When they arrive, to keep things apples-to-apples, I'll swap them onto the solenoid currently in the car, which is currently carrying the 0.070" WD fluorosilicone rings. That way the only thing that changes is the ring thickness. Should be interesting, especially if the thickness increase of 0.033" perceptibly changes the HPFP's behavior.

 

My HPFP readings:

Before a cold start:
Around 70 PSI. +/- 5 PSI for a the few times I checked.

Idling or coasting (injectors off):
800 PSI +/- 100 PSI depending on RPM

Engine under any load:
Immediately jumps to 1500 PSI +/- 100 PSI

Note that my graph is very stable in comparison to yours. Unless its switching from "Idling / costing" mode to "load" mode it appears flat.

 

Very interesting. "Performed HPFP Test Plan, checked oil level of pump and found it low. HPFP Faulty. Replaced HPFP."

Can someone get ahold of the official HPFP test plan?

Mine had been having difficulty starting from cold temps for a few months, sometimes could not start at all. It was also interementinaly and briefly cutting out while driving. Took it in to the dealer 3 times. Every time they found no codes.

First time they said they found blowby on a plug so because it could be the loose plug and no codes they would not replace it then. Tried explaining that one loose plug would cause two cylinders to misfire at most, not all 4 at once. Also would not cause low pressure readings from my OBD reader. Charged me $150 diagnostics fee.

Second time I towed it in. Would not start at all at home. Thank god my insurance covered the 60 mile tow. I found out later someone screwed up and they were not supposed to cover it. Of course as soon as it gets the dealer it runs perfectly and no codes.... However I finally got ahold of the foreman and he said that if it keeps happening to contact him and he would take care of it.

Third time I wait a month of dealing with it off and on before contacting him. I was getting close to the 120K end of warranty. Still no codes or problems in the shop. He said in the report that it cranked no start in the shop so that it would get approved.

 

All of this is consistent with the behavior I see from my junker HPFP with the fluorosilicone o-rings (excepting its cold start problems) once it is warmed up. When coasting the fuel pressure looks so smooth I actually thought “patient in good shape on ER, who knew.”

The difference with mine is that it isn’t that hard to make it get unstable. Not easy, but not hard either. And with my 2013 HPFP with the Viton o-rings, the graph was *really* unstable.

Based on all this and your other post with the detail of your HPFP replacement experience I suspect:

(1) the thicker fluorosilicone rings will help but not cure the issue.

(2) final cure, if possible, will be from getting the o-rings just right, figuring out what the deal is with these pumps losing oil (and compensating for that through pump refresh), and possibly some work on the mechanical of the solenoid (though I hope I don’t have to try to figure out how to tear that down).

I would also love to see the “HPFP Test Plan.” Maybe we can find one on HSN? QVC?

 

New update. Good and bad news, but good information nevertheless.

I got the thicker fluorosilicone o-rings from McMaster-Carr. Bottom line: the wall diameter was too much. No dice. In order to work with a different wall diameter I'm going to have to find a product with a wall diameter between 0.070" and 0.103". McMaster-Carr does not have such a product listed on its website within its fluorosilicone o-ring lineup.

Detail: Because the inner diameter was the same as the original rings, getting them onto the solenoid was not an issue. However, the solenoid would not insert into the pump body. I put enough pressure on it to make it clear I would pretty much have to put my whole body weight into the thing to get it to insert -- which also meant it would probably never come out again (and that's aside from any damage/nonalignment from insertion itself).

Where this left me was "ok, I have this junker HPFP, I know how it behaves with the fluorosilicone o-rings that fit, but I do not know how it behaves with Viton rings, and that matters because each individual HPFP I've had has had unique behavioral characteristics even in failing/being weird."

If you've been following the thread, you'll recall that I tested Viton rings on the HPFP that came with the car used (the HPFP is a 2013 genuine replacement for the original-manufacture HPFP, swapped under warranty under the car's first owner). However, I had not tested Viton rings on my junker HPFP, because the Viton rings have a min operating temp of -15F -- unrealistic for many cold climates where Minis are running around all over the place.

Since the thicker fluorosilicone rings I got are a no-go and I do not have (at present) fluorosilicone rings thicker than the originals but thinner than the new ones, I said, "well, let me try the junker HPFP with new Viton rings of identical sizing, and I can do a materials-only apples-to-apples comparison on the same HPFP."

The results:

- Warmup issues are present regardless of the material, but the flurorsilicone warms up faster and more reliably.

- Failure behavior is still observed regardless of the material, specifically the half-engine light popping up after things have warmed up. However, this seems to be more common with Viton than with fluorosilicone.

- The Viton rings seem to lead to more consistent HPFP behavior, meaning that if it's flaky, it's flaky, rather than ebbing and flowing between flaky and hot-damn-this-is-great like the fluorosilicone rings. This makes a certain sense -- the Viton rings are harder, so they're going to stay in a tighter range of temperature-driven expand-contract, and to the extent that expand-contract is minimized, you get more consistent behavior good or bad.

- In terms of hardness, the gasoline-exposed fluorosilicone rings, including the original bottom O-ring, are palpably "squishy," even more so than the brand new fluorosilicone rings that have never been installed.

On balance, I like fluorosilicone more -- when it works, it works. However, both of these tests indicate that something is amiss besides the O-rings on the solenoid, because I wind up with half-engine lights and low fuel pressure warnings with both materials. The incidence, frequency, and nuances of the behaviors change, but there are always issues to contend with in some way.

My goals now are:

(1) find a better sizing of fluorosilicone o-rings from another manufacturer, since I see none on the McMaster-Carr website. Does anyone out there have any supplier suggestions where one can order online? The two ring sizes needed are:

- Inner Diameter (ID) of 5/16" ("top" or smaller ring)
- Inner Diameter (ID) of 3/8" ("middle" ring)
- Wall Diameter (wd) larger than 1/16" (0.070") but smaller than 3/32" (0.103")

Alternative materials option: Viton o-rings that have been tweaked by their manufacturer to have a lower minimum operating temp than -15F. I know this is possible, as McMaster-Carr has Viton rings with different min op temps, but I have not seen one of *theirs* with a lower min op temp than this. Since I have personally been in Chicago at -22F, it is sensible to require o-rings that will go well lower than that too. If someone has a different Viton option here I'm very interested in it.

(2) Figure out what to do about the "rest of the HPFP," that being cracking it open and ensuring that it has the right amount and kind of oil within.

I figure I can move to task 2 when I/we all figure out task 1. Input welcome, and hope all this information is helpful.

 

Nice update. I'm looking forward to you cracking one open to check the oil situation. Have you contacted Blackstone to see if they can ID the oil?

 

Not yet. Been pretty busy the last couple of days and tied up in full until next week, won't be able to touch the car. I actually crammed this bit of activity in last night because I didn't want to spend the next 7 days overthinking o-rings but not being able to touch the car

I'll take on the Blackstone question next week. In the meantime, if anyone can find o-rings to fit the plan I can at least order something.

Separate note: the business of removing the solenoid without removing the HPFP? Technically possible but not worth it in my case. Since I have the Continental pump I would have to do some working around the electrical connector, while the HPFP is on-engine, to get to one of the solenoid bolts. The fuel lines and electrical connector have to be disconnected no matter what, the former for access and the latter for safety "because gasoline." In that context it's much easier and more practical to pop the 3 bolts holding the HPFP to the engine and take the whole thing off, and doing so is quick and easy if you've already got your hands that deep in there.

 

chiming in again

cjv2, There are let's say three parts to the HPFP.

1- The solenoid
2- The O rings
3- The body

You're whole experiment dwells around the O rings and you have not (or have you) confirmed if the other 2 parts are in good working order?

In order to test the O rings, you need a healthy HPFP that you know works fine/great. Then you take it and sacrifice it to test the replacement O rings. Only then, you can truly say the O rings work or not.

If that step is verified, then you move to the solenoid and conduct the same experiment on a known healthy HPFP.

do you get my point?

 

You are spot on. There are complicating factors though, so I'm having to move a little more slowly through this.

(1) I do not have a healthy HPFP. I have three non-healthy HPFPs, that behave differently from each other in their non-healthiness, and a fourth HPFP that is suspect but has never been on the car. The fourth one is out of the game for now, so I'll focus the rest of my comments on the remaining three.

(2) Since my three non-healthy HPFPs behave differently from each other despite all three being non-healthy, and I do not have a healthy HPFP, there is a sensible focus on understanding two things: (a) how are these three HPFPs different? and (b) what apples-to-apples changes on a single HPFP can I make to learn about how these o-rings do and do not matter?

(3) There is an outstanding question: "can you rebuild, to operating potential, an HPFP?" That is an overlapping but separate question from the interactions with the rest of the vehicle, and I am trying to get some clarity on the nuances of that question by eliminating the behavioral differences *between* my HPFPs. If I can get all 3 to behave the same way -- even if behave means misbehave -- I've hit a baseline that is reproducible, and then I can turn to other parts of the vehicle. Right now I have 3 oddballs, joined only in the generic fact that they are non-healthy.

I am clear that a functional HPFP with the rest of the car being weird (say, a fuel pressure sensor requiring replacement) will mislead you into believing the HPFP is a problem. However, my three HPFPs are confirmed non-healthy. One (the newest) is actively leaking oil and intermittently weird, the 2013 one is just plain wacky in a different set of behaviors that are more pronounced, and the junker is somewhere in the realm of "subpar operation but ok most of the time."

So in essence, at the moment at least, I'm doing a bit of an exercise on HPFP understanding as a subset of the larger problem of fixing the whole HPFP thing entirely.

On the "how are these three HPFPs different" front, I've actually figured out a handful of things from all the o-ring experimentation. The biggest one is simple: I can swap o-rings to high heaven and the rest of the HPFP body remains a live, participating variable rather than a hypothetical one. Two HPFPs that have had new Viton rings installed have behaved in very different ways. Yes, both non-healthy, but very differently-nuanced flavors of non-healthy. So once I've settled my understanding of the o-rings, I'll be moving on to the HPFP body, again with a goal of establishing an all-three-HPFPs same-behavior baseline.

On the o-ring side of things, it seems practical to pursue finding the *right* O-rings, especially since a Viton-for-Viton swap (I am pretty sure the original o-rings are Viton) appears to be out of the picture.

As to the fuel rail pressure sensor, I'm not at this point looking to drop $200-$400 on the fuel rail replacement given that I have three differently-behaving HPFPs. They all behave differently *from each other* under the same single pressure sensor, so they are their own variables. But once I can get them to behave the same as each other under whatever the existing sensor's condition is, I plan to replace the pressure sensor.

Just to be clear, the differences in behavior between the three HPFPs are not minor. They are behaving much more like different-aged siblings than like twins or triplets.

Regarding the solenoid itself, I haven't figured out what to do with it other than o-ring swaps. Not to say there is nothing that can be done with it, but I haven't yet had the time/opportunity to figure out how to break the bugger down. I would love any input on this, if anyone has done it. Frankly, I'm kind of suspicious of its electronics but I don't know how one would meaningfully do anything with that either -- solid state electronics and all that.

Anyway, all slow (and frustrating) but there *is* a method to the madness.

 

Is the testing car in good running order to at least eliminate the pressure sensor? also you dont have to spend that much on the rail (https://www.ebay.com/itm/09-15-mini-...ty!19111!US!-1).

ohm out the solenoids and get the readings.

in order to do an accurate test, the testing tools and environment need to be calibrated/healthy.

 

The rest of the car is healthy so far as I know, possibly excepting the pressure sensor.

But your timing is solid — something just (literally) happened here post-Viton install and it may point back at the pressure sensor. Item ordered and we’ll see in a bit over a week.

 

Ok - sorry for the cryptic reply. Today was a "fun" Mini day.

As noted I switched the junker HPFP from fluorosilicone rings (been in there a few weeks now) to Viton rings (brand new from the package, same kind/specs as I had installed in my 2013-vintage HPFP). Last night I did road testing, blah blah, did so for a good 1/2 hour easily, probably more.

Today I started up the car, got cold start stammering and misfires and all the things a dying HPFP sets up at cold start. But it stumbled a *lot.* Stop the engine after a bit. Start again and rev immediately up to 5K and hold.
Settles in. Half engine light clears. Good.

Or not so much.

While driving along, instead of just getting a half engine or something else, the engine started stumbling -- likely fuel starved and possibly misfiring --
but falling to idle doesn't help it. Stopping the car doesn't help it. Feels like it's going to stall clean out. It made clear it wasn't going to stop doing whatever it was doing, period.

Stop the car. Restart the car. Misfires, stumbling, etc. Got the car to a safe pullover. Pop the hood. Get out, smell rotten egg smell (sulfur). Smell under the hood. Nada. Smell behind the car. Hmmm. In a light industrial area so not clear I didn't drive into the smell. Ultimately concluded I didn't, it came from the exhaust. Google it up, points to a trashed cat (!!!?!?!?!?!!!) or fuel supply problems (uh, "whew?").

I'm 2-3 miles from home but this car is definitely not happy, and if the cat isn't actually trashed, continuing to try to force things will likely trash it. My money is on the fuel supply (duh, this is the entire conversation).

MiniToBe, this is where you come in. While you were posting the link to that fuel rail on eBay, I was doing what's in the last paragraph. I found your post, and I ordered the bugger from my smartphone while standing next to my Mini with its blinkers on.

Lots of running around later to de-strand myself (not much, just drama, was still reasonably near home) but I leave the Mini where it is. I get home and walk into the garage to grab tools, an HPFP, the Bentley manual, and every tool/doodad involved in an HPFP swap to date. I find on the ground, behind where the exhaust was, is a directional liquid splatter pattern, like spray from a bottle -- but not liquid. Soot (carbon). Black as coal.

Hmmmmm.

I drive my not-Mini to the Mini hoping to get it off of roadside and into a parking lot. I'm prepared to swap the HPFP out right where it is (seriously, I can do this in 15 minutes now if the car is cold). But my hope is that whatever is temperature-driven in this fracas will level it out. My hope is also that this isn't due to something like the rings I installed being damaged in some weirdo way that would explain all this, and for some reason not flaming out until today.

Cross fingers, start Mini... Mini starts right up. No stumble. No nothing. Ease the car into the parking lot it's next to. Monitor a bit, shut it down. Hop out of car, smell under hood. Nothing. Smell behind car. Interesting -- no sulfur smell.

Hmmmmmmm.

Ran off to do errands (in the not-Mini). Later in the day a friend brought me to the Mini to try to limp it home. Started it. Grumblesputter but it leveled out on its own. Let it idle for 2 full minutes more. It settles further. Sounds and feels 100% normal (though I know better than that).

Gently drive the car home. On even the slightest uphill grade it starts trembling. Put it in a lower gear to compensate. That helps somewhat but in some places I just have to back off the gas, so I'm sub-speed limit in a 45 zone. That's OK. On steeper uphill grades I'm all the way down to M2 (remember, this is an auto) to avoid having the engine shaking itself around. (Side note -- this is consistent with previous HPFP stumble, for those wondering how it "feels" and what it acts like. It acts like you've got the RPM too low and the gear too high and you're going to kill the engine, even when that isn't the circumstance you're in).

So now the Mini is in the garage. I caught some faint sulfur smell. I am attributing that to the minor engine stumbles climbing the driveway (decently-sloped hill). Nothing nearly as obvious as the first go, where the car had been sputtering for a while and for some distance.

I won't have the replacement fuel rail until next week. Mini is in drydock until it arrives and I can do the install.

MiniToBe, thank you big time for the link and for having some oddly amazing timing.

Separately -- "ohm out the solenoids." Can you be more precise? I certainly know how to use a multimeter to check resistance, but I don't know what values I'm looking for, across which contacts, on which solenoids (since it sounds like you're thinking plural -- meaning not just the HPFP solenoid?).

 

What a journey! Lol

The HPFP solenoid has only two wires. Measure resistance for each pump to see if the coils are at least within range of each other.

The seller you bought the item from is a friend of mine now. I bought a lot of items from her for my minis.

Once i get my hands back on my countryman, I tag along and provide you some valuea too. I have two test HPFP that i can play with later.

Lots of things to do but little time. I have an N14 engine to rebuild next.