Bucking underload and moving misfire

Does anyone have any good write ups on cleaning the spill valve for the hpfp? It’s gonna be two days on the fuel pressure relief valve so I might as well clean the spill valve while I’m here right?
 
2008ms3nick said:
Does anyone have any good write ups on cleaning the spill valve for the hpfp? It’s gonna be two days on the fuel pressure relief valve so I might as well clean the spill valve while I’m here right?
Click to expand...
You mean this?

https://www.mazdaspeeds.org/index.php?threads/hpfp-o-ring-rebuild-michael-rey-facebook-kit.8069/

Ps if you're looking for a specific thing in mso the best way to find it is via Google like this thread I knew existed so I put "hpfp service site:mazdaspeed.org" into Google first link yields this excellent thread. The "site:mazdaspeed.org" keeps all results strictly to mso
 
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So I just got the new pressure relief valve in today and I’m checking it to see if I can blow air through it and I can’t blow through this one either? So what’s my next step? Was my old one even bad? Why did I order one if the new one is acting the same?
 
Test it like on the vehicle? Of course I’ll make the instal tomorrow I was just confused on the valve because it was mentioned I should be able to blow through it and I can’t, even the new one is sealed with no air flow, is that because they are spring load to a certain pressure? Sorry just new to the game with these direct injection cars I don’t mean to come off rude I appreciate all the advice given.
 
Yes, like on vehicle. I'm not knocking being able to diagnose a bad valve via blowing on it. Was implying that your lungs are not calibrated, or perhaps even capable of cracking the valve open.

No need to apologize. I come off an ass, but I do really want to resolve your specific issue.
 
I believe the blow test only shows you that a valve is bad, not necessarily if it was good or not. If it has failed, you might be able to blow right through it. A working one opens at what, 1850 psi? I can't blow that hard.

For shits and giggles I tried it on a PRV I removed from my car a couple weeks ago that I'm pretty sure is good (or at least, replacing it didn't fix my problem.) Can't blow from either end.
 
One hefty check valve, as others said try the new one on your car. With your old one you said it was corroded into your fuel rail, I'm curious as to how dirty the rest of that rail is, mainly spill valve and injectors, those can all add to it, intake valves may need a cleaning too. Those are all later things get that new prv in and see what happens
 
Put the valve in today along with new inter cooler boots and new plugs and oil and she is running but with a p0113 code and she sounds like she’s misfire still but no misfire code
 
Cleaned the mass air flow sensor and it’s still running like it has a misfire


Edit- fuel pressure at idle is about 700-750
Is there maybe a idle relearn I have to preform from it sitting with no batter for two days ?
Maybe a ecu reset?
 
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Disconnect the battery for about 10 minutes or so and it'll reset the ECU and force relearning fuel trims, but idk if it impacts idle fuel pressure at all.
 
It takes roughly 20 miles for the trims (long term and short term) to re-learn. I really have no idea if it will impact pressure, my first assumption is to say no, but it's worth a shot. Only downside is having to reset your radio, haha.
 
And it won’t hurt to drive it while it’s idling rough like this? Like when I push the clutch in it drops to about 300 rpms
 
I guess maybe that depends on how rough the idle is. What happens if you blip the throttle or hold it at like 1500rpm, does it seem to even out at all to indicate it might only be an idle issue?

P0113 is IAT sensor (part of the MAF), have you double-checked that the oring didn't get twisted or pinched on reinstall? Harness is fully plugged in and the wires look good? You gave the MAF sufficient drying time after spraying it with MAF cleaner?

I also always wonder what fuel pressure is up to anytime someone has a stumbling or chugging issue, but 700 at idle should be plenty high... actually I think idle pressure is usually more like 400-450.

Ed; just saw the edit about rpm dropping at clutch-in. That is definitely weird and if you're already in neutral then clutching in shouldn't affect anything. Curious.
 
So I unhooked the battery for 20 minutes and started it back up, the idle is still a little rough and when I give it gas it idles up but still a bit rough
 
Update

I started the car this morning and drove her around and she threw a cylinder 4 misfire and a p0300 random misfire on the drive

edit- I purchased a coil at Autozone today to try that after work on cylinder 4 just in case.
 
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Another new coil in number four and she still has a rough idle I’m all out of ideas here guys I could really use some help
 
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