HPFP help!

Lucky for you @Enki wrote most of the answers to hpfp problems on msf. Take his advice

Yeah but...
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Not throwing any codes?
no codes, but been checking for them pretty frequently. my relief valve test got up to 1800 before slowly dropping, I've seen it's supposed to be at 1850 before that happens. would you know if this is an issue with my rv?
 
how about my pressure dropping down to 270-300 on deceleration when fully letting off the throttle in gear? pardon my mechanical ignorance :(
also my cold in tank pressure has seemed low now. around 48-54psi
 
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The HPFP will work with 10 PSI feeding it. The engine doesn't need high fuel pressure when the injectors aren't even firing (off throttle, engine braking).

The fuel pressure is modulated based on expected flow and minimum (yes, there's a certain amount of time the injectors have to stay open due to physics) injection time. If the pressure is too high the car will run rich, and from the factory that would mean a fine from the EPA due to emissions. The only time you really need to watch rail pressure is under load and boost, in which case you want over 1600 PSI minimum. 1400 PSI is getting dangerous ish.

As a side note, I've personally driven with a crapped out HPFP two hours between cities; this was with only 50-60 PSI at the rail (not recommended, but doable in an emergency).
 
The HPFP will work with 10 PSI feeding it. The engine doesn't need high fuel pressure when the injectors aren't even firing (off throttle, engine braking).

The fuel pressure is modulated based on expected flow and minimum (yes, there's a certain amount of time the injectors have to stay open due to physics) injection time. If the pressure is too high the car will run rich, and from the factory that would mean a fine from the EPA due to emissions. The only time you really need to watch rail pressure is under load and boost, in which case you want over 1600 PSI minimum. 1400 PSI is getting dangerous ish.

As a side note, I've personally driven with a crapped out HPFP two hours between cities; this was with only 50-60 PSI at the rail (not recommended, but doable in an emergency).
Same, my PRV was bad and I could only build like 60 psi but I was able to drive it as long as I did not get deep into the throttle and start to boost. I drove it to work like that for two days before I figured it out.
 
The HPFP will work with 10 PSI feeding it. The engine doesn't need high fuel pressure when the injectors aren't even firing (off throttle, engine braking).

The fuel pressure is modulated based on expected flow and minimum (yes, there's a certain amount of time the injectors have to stay open due to physics) injection time. If the pressure is too high the car will run rich, and from the factory that would mean a fine from the EPA due to emissions. The only time you really need to watch rail pressure is under load and boost, in which case you want over 1600 PSI minimum. 1400 PSI is getting dangerous ish.

As a side note, I've personally driven with a crapped out HPFP two hours between cities; this was with only 50-60 PSI at the rail (not recommended, but doable in an emergency).
this definitely gives me peace of mind about driving it to and from work which I don't really have a choice on lol until tomorrow morning at least when I can pull the pump and try to clean as best as I can without pulling the internals out for the sake of avoiding another fuck up :shakehead:
 
Just abandon the queen, get over yourselves and your low value Canadian dollar and apply for statehood already.
Little off topic from poor OPs thread now aren't we? Leaving the common wealth is really doesn't have a benefit, nor does it really have a benefit IMO. However joining the USA? Not a chance, I immigranted once I'll do it again if that ever happens this time away from north north america. While I like being neighbors to the USA and we seriously need to fix our economy as we used to almost be on par with the USD doesn't mean I or probably the majority of Canadians want to live there.
 
so going over my original pump parts that were left over from the local shop when they tore it apart to extract my corksport internals and I found that the used pump I bought to get a new screw nut (supposedly off a cx7) had autotech internals in it :eusa_doh:

guess it doesn't really make a difference unless my CS internals are failing and thats the reason for my pressure dropping randomly.
on another note, I noticed that the electrical connection on top of my spill valve doesn't click into place like my original one did. should I swap the spill valve off my now parts pump?can the parts can be interchanged? thanks guys!
 
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so going over my original pump parts that were left over from the local shop when they tore it apart to extract my corksport internals and I found that the used pump I bought to get a new screw nut (supposedly off a cx7) had autotech internals in it :eusa_doh:

guess it doesn't really make a difference unless my CS internals are failing and thats the reason for my pressure dropping randomly.
on another note, I noticed that the electrical connection on top of my spill valve doesn't click into place like my original one did. should I swap the spill valve off my now parts pump?can the parts can be interchanged? thanks guys!
Pretty much everyone who owns these cars has a broken spill valve plug just get a plastic tie and tie it on there.
 
after cleaning up pump and reinstalling the car is feeling better but my idling ltft are fluctuating. sometimes around -10 sometimes -13.5. do these numbers sound off? under load I've been around +0.6
 
Don't check idle trims until car is hot.

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Also, fuel trims at idle have little to nothing to do with HPFP issues, pretty much ever.
 
Your rich LTFT's could be from some kind of boost leak.

Without any codes, it's really a matter of checking/testing things.

How many miles are on your HPFP now?
 
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