Fuel Cut or Possibly a Bad Fuel Pump.

zoomzoomMSP

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2003.5 MSP
so just recently i have noticed that during a 3rd gear WOT acceleration the car has a hesitation. (so far its 3rd gear only) so i set up my dashhawk to monitor my fuel pressure and sure enough the fuel pressure is dropping to around 500-600 psi. i know that car should be around 1600 psi so i know this is the hesitation im feeling. the other thing is that the temp has now dropped into the 30's (F) so i was also wondering if the colder temps may be giving me a fuel cut. i have a feeling its the pump. my mods are in my sig. nothing radical but i might be to a point where i need a new/better pump. if anybody has any thoughts i would appreciate your input.
 
CDFP probably not able to keep up with the mods. Also, you're honestly running too much to allow the hypertech to properly keep up. I wouldn't run anything more than an intake with hypertech.
Two things: Get some cdfp internals like autotechs, and get an accessport.
those two things will allow you to up the boost and maintain pressure more safely.
Don't go WOT until you do this though, the fuel cut is bad.
 
If you had the mods on there in the warmer months and it was fine then you can see that it is attributed to the cold weather change. Never the less i would still get the internals now that you have seen it do this.
 
i feel i really need to get the fuel pump issue addressed, so at this point im debating on getting the internals for the rebuild or getting a new pump all together or buying one off a member if i could find one. so any thoughts on how i should proceed would be great, you guys having good luck with the internal rebuilds or should i just get a new HPFP.
 
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CDFP probably not able to keep up with the mods. Also, you're honestly running too much to allow the hypertech to properly keep up. I wouldn't run anything more than an intake with hypertech.
Two things: Get some cdfp internals like autotechs, and get an accessport.
those two things will allow you to up the boost and maintain pressure more safely.
Don't go WOT until you do this though, the fuel cut is bad.

Agree that his fuel pump has taken a dump and needs upgraded internals.

Respectfully disagree with the generalization that HT ought not be a tuning option for anything more than a simple intake.

Please see my mods below, which includes a fully catless 3 inch downpipe and catless race pipe, CAI and one step colder plugs Attached is a pdf version of a csv data log made by ScanXL Pro software dongled to the OBD II port and a laptop. Resolution is low as I was logging a lot of other stuff I have edited out to get the essentials on a single page for this reply.

I've also used this data to capture and chart the data in Virtual Dyno, which is also attached.

OP has a Dash Hawk. Perhaps he could post his log for review. No new logs, or WOT driving, however, until the fuel pump is upgraded. Some of us seem to have stouter stock pumps that others. I guess I'm lucky.

In my limited experience with HT and data logging, I find that it can support just about any bolt on mods so long as the fuel pump keeps up and the stock K04 is the only turbo used with it.

There are a lot of OTS stage 2 AP maps not doing as well, and some AP custom tunes that produce no better results, but which push the K04 way to hard with sustained high boost out at redline and AFR's that are too lean to be compatible with this DISI engine's design considerations to purposefully run extremely rich at high rpm to provide combustion chamber/cylinder cooling through that unburned fuel.

Please note that I do not consider Virtual Dyno numbers to be the literal equivalent of a chassis dyno. However, many pro and semi-pro tuners on the MSF board are using this software to make comparisons. It is against those posted logs that I make this comparison. In the absence of meth or E-85 tuning custom tuning on AP, these results hold up pretty well, IMHO.
 

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So i just talked with the guys at Pt-Performance and he said that i should check the low pressure pump in the tank, he said a number of guys have been replacing the HPFP and still having an issue and its the one in the tank that is the problem. just thought i would put that out there for other members possibly dealing with this type of issue.
 
So i just talked with the guys at Pt-Performance and he said that i should check the low pressure pump in the tank, he said a number of guys have been replacing the HPFP and still having an issue and its the one in the tank that is the problem. just thought i would put that out there for other members possibly dealing with this type of issue.

I disagree with that. The vast majority of people have had the cdfp as the issue and that's what I recommend here. Autotech internals are a safe way to go. Plus, it's honestly a lot easier than messing with the in-tank pump, which has RARELY been an issue.
 
^^MSMS3^^ thanks for your post and the charts, great info. ive been really happy with my Hypertech, and ive been running it for almost a year with the current mods and no problem until now with the fuel pressure issue. Fuel pump has been nagging away at me even before i had an issue, never cared for potential failure in any part. are you suggesting i go with internals?
 
^^MSMS3^^ are you suggesting i go with internals?

I'm on stock pump, so I'm not the guy to ask. But I think Chimmike is correct that the Autotech internals are the way to go. That is what I would do if my pressure drops. Autotech has been widely known for years and respected in the VW-Audi forums as the best choice for high pressure fuel pump internals. We use the same internal parts as the do for the high pressure pump in their 2.0L engine.
 
looks like the autotech internals are $400......... seems like a big nut for internals...... i know autotech is good stuff i had a few goodies on my cars back in my VDub days. ill give them a call and see what they have to say, the install instructions dont seem to bad.
 
install really isn't bad. they don't have specific instructions for ms3's, but basically remove intake, TIP, battery/ecu.
unscrew lower fuel hardline, disconnect fuel lines, unscrew reverse t8 bolts, pull pump, replace internals, reinstall.
 
install really isn't bad. they don't have specific instructions for ms3's, but basically remove intake, TIP, battery/ecu.
unscrew lower fuel hardline, disconnect fuel lines, unscrew reverse t8 bolts, pull pump, replace internals, reinstall.
thats really not a bad how-to
concise, i like it
 
kmd looks to make a really nice set of internals as well as autotech. kmd looks to be about $50 cheaper. ive done alot of research on the install instructions/how to's and it doesnt look to bad.
 
Be warned on KMD's. They're on their 4th or 5th version because the earlier versions failed, seized, scarred, or otherwise. Autotechs are the original design, methinks because they use good material from the get-go rather than 'experimenting' with cheaper material or different design.
 
i also noticed that AWE Tuning offers the install tools with the internals...... thats a plus, anyone have luck with this brand?
 
Never heard of them. If you don't already have the tools you need to swap out internals on the ms3, you probably shouldn't be doing the install yourself, lol. The only thing you should have to buy is the reverse torx bit. I think it's a t8
 
i also noticed that AWE Tuning offers the install tools with the internals...... thats a plus, anyone have luck with this brand?

I remember them from when I had my Audi TT. They generally have good quality stuff, but I know nothing about their hpfp internals. I didn't find it on their website either.
 
Ha i knew somebody would flame me about the whole tool thing. yeah i think the torx bit is the only one i dont have. i came across AWE Tuning in a couple of the VW Forums and some other Mazda Forums, i never heard of them until then either. the more and more i look its seems like Autotech is the way to go. but the more i look the more i find..... for example APR makes a super nice looking rebuild kit for the 2.0T VDub crowd. but its pricey. Looks to come with more pieces for the rebuild though.

what are you guys thoughts regarding an upgraded spring?
 
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