[SOLVED] 0V HPFP randomly dies

The car came with a tune. "Olympic Motorsports Stage 3 tune" Not sure how it was tuned or how reputable that tuner is, but i switched over to a OTS tune from COBB. Stage 1 tune, and i do not really go into boost that much as i want the car to be in top shape before i start to push it.

I have checked for boost leaks, and found several. I have since replaced all the vacuum hoses, re-circulation hose coming from the BOV, and the silicone on the FMIC piping. The car ran way better afterwards, still the LTFT issues though. I tried replacing the O2 sensor since i do have a new O2 sensor, but it is stuck on there! I noticed the down pipe ins't OEM either, it looks like a cheapo ebay down pipe, but no exhaust leaks or cracks.

 

If you're running a Cobb intake and their matching OTS tune, then your mafcal should be within spec well enough to not cause issues.

I had fuel trim and afr issues when my primary o2 was bad; took me a long time to track down since the car wasn't actually throwing a code for it. I don't think that's related to your strange hpfp readings but it may still be worth swapping if you can manage it. the ebay downpipes work fine as long as it isn't leaking.

 

If that box is not connected to anything it will be a vac leak so that is something to look at.

 

I've never heard of olympic motorsports. http://www.olympicmotorsports.com/2004-wrx-sti/ ?? Your tune is probably garbage.

Boostleak testing howto: https://mazdaspeeds.org/index.php?threads/how-to-boost-leak-test.6276/

 

Yup that's them. I purchased the car in Boca Raton, and that's their location.

I think i reconnected them all, but i wouldn't mind deleting the box itself. I have rubber caps i can put over the nipple on the intake manifold. Can i just disconnect the actual actuator motor itself, and just leave the plug there? If anyone can help me clear some engine codes such as for the EGR and the VTCS that would be appreciated.

I believe my O2 is bad because the car was running rich for a long time. It's not throwing a code for it, but i can tell its not OEM, or even an OEM quality replacement. The wires look cheap, and the plugs feel cheap. I purchased an NTK O2 sensor. I noticed the down pipe has an extra bung for another sensor, can i put an AEM Wideband in there? or what can i use that for? It's directly next to the OEM wideband sensor.

Today i'lll try some troubleshooting, and post the datalogs. One step at a time.

 

You want to leave the black box plugged in. It will trigger a cel if it is unplugged

 

Hey guys,

So a little update. I went to install my hpfp internals to find that only 2/3 bolts were on the actual hpfp. One of the bolt was so stripped i couldn't remove it, and another has no threads on the hpfp housing so it just didn't have a bolt in there. I went ahead and added another bolt while i order a new hpfp, and hpfp housing.

My fuel trims are at -0.16 steady after adding the 3rd bolt. The bolt cannot be tightened as the threads on the actual housing that holds the hpfp are destroyed.

At lease i figured out my issue. Now... where to find a hpfp, and housing before the weekend in south florida....

 

You can probably take a Dremel I'm and shave it down so you can remove the hpfp or drill it out, but I appreciate wanting to say screw it and let's toss on a new pump after that. If you buy a used pump I'd pickup a hpfp rebuild kit and clean it and put new o-rings in.

Here's the hpfp can housing, maybe there's a Wreckers that has a speed near you?
https://www.jimellismazdaparts.com/products/Mazda/2013/Mazda-3/HOUSING--REAR/1889366/L3K910190A.html

 

I ordered a USED OEM one from the same year MS3. I also have the E85 safe CorkSport o ring rebuild kit which brings allen heads instead of reverse torx.

My belief is that this car saw A LOT of E85 over the years as most of the fuel system is very dirty. My spill valve is showing signs of going bad as well. When i shut the car off it hold 1000PSI does not drop. When the car is first started its at 0PSI until it gets to operating temp, then it stumbles from 0 to 1500 psi then after about 20 mins of driving no more fuel issues, pump will hold 1500+. It does fluctuate a lot, going from 1500ish PSI to about 280ish PSI and back and forth.

Fuel system parts I've replaced since problem originally started:
CS Injector seals
GMB Remanufacturing injector to fuel rail seal kit
HPFP to fuel rail o ring

Parts i have that i have not replaced:
CS HPFP Internals
CS O-Ring rebuild kit

I will not be replacing anything else until i get this figured out.

My fuel trims were very good after adding the bolt to the hpfp, but since there is almost no thread its loose again and the LTFT are all over the place. I will ocntinue to update as much as possible, i will aslo attach another data log later today.

I am frustrated to say the least. I did buy this as a project though so i cannot complain!

You guys have been awesome with helping me figure this out.

 

Probably incorrect. The worst pump I ever saw was from a CX7 that only ever saw pump gas. Chances are it saw a lot of low quality oil.

Edit:
You should clean the pump, and "e85 safe" orings are not needed.

 

Oh i'm not planning on running e85, thats just what they market it as.

It's from Corksport : https://corksport.com/mazdaspeed-e85-safe-hpfp-o-ring-rebuild-kit.html

 

You don't need that unless your existing orings are damaged, and even then you can get normal ones for a LOT cheaper.

 

Well the way i see it is this car is almost always parked, if one day i did decide to go ahead and use E85 i wouldn't have to rebuild the pump again. Also, the reason for the o-ring replacement is the fact that the pump i current have was only really held in with one bolt, and that it might have dislodged back and forth causing damage to the o ring.

Again, i am new to this so i'm just trying to cover everything while i tackling this.

 

The only oring that could be damaged by that back and forth action (which is unlikely to happen, considering) is the one that only prevents oil from leaking out of the head.

You really, really, really need to look into a HPFP cleaning guide.

 

I finished removing and cleaning the HPFP yesterday. I used lighter fluid that contained Naphtha like you recommended. I reinstalled with a new gasket that mates to the head. I still have 0 PSI. I still have code P0192.
I have never replaced the Fuel Rail pressure sensor, so I’m not sure if that’s it.
A thing to note though, when it starts it will read 0PSI, once it warms up, the problem completely goes away 100%. It reads perfect, it doesn’t drop Pressure.
What the heck could cause this?

 

Well considering that the injectors won't spray any fuel at 0 psi suggests that it's a sensor issue.

 

Sensors die, you would not be the first person to have had a fuel rail pressure sensor die. Even if you've never touched it.

 

Hahahahahaa so guys, I started fiddling with my wiring harness and the car kept dying. My fuel pressure is also jumping when I move the harness. What is this portion of the harness called?
It connects the fuel injectors, the coil packs, and the hpfp.

 

I would pull it out and inspect it. If you are handy you can clean it up and tuck it.
https://mazdaspeeds.org/index.php?t...-build-maximum-carnage.7025/page-6#post-65746

 

Just wanted to throw an update for anyone dealing with this issue.

I finally fixed what was wrong with my car. It was a mix of multiple things.

Symptoms
- Negative fuels trims (-20.88)
- HPFP reading 0PSI
- Car randomly dies under acceleration

Fix
- Fuel pressure sensor was dead. I replaced with a bosch that claimed it was the replacement for my 2009 Mazdaspeed 3, BUT it did not function properly. It would cap off at 1650 PSI and car would shudder. (Correct Part # for sensor is 0261545053 This is the 140 BAR. https://www.bosch-motorsport-shop.com.au/pressure-sensor-for-liquid-140-bar)
- FMIC piping rubbed against wiring harness (from previous owner.) and frayed wires leading to my HPFP.
- O2 Sensor was also dead, reading incorrectly. Fixed with NTK O2 sensor from Rockauto.( NTK 24357 {#L33X188G1C} 5-Wire )

If having issues i would suggest to check on these items first.

Thanks to everyone who helped me diagnose this, and find the correct parts for my car.