Using the USP hi-flow LPFP: with or without the hi-flow control module?

I will look into this upgrade or replacement if and when I begin replacing hardware. I'm in "finding the root of the problem" mode right now before I go on replacing anything more. The J17 fuel pump relay provides current to the lpfp...so given that error code, I will replace that before trying race file before trying DM again. At that point I will see if any codes returned, deal with those if present, and then move forward with either replacing everything we can think of...or just run it and wait until something completely fails making it easier to detect.

high_octane3541 said:

Get the torqbyte pm3

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eurocars said:

You don't need an upgraded module with the TT-RS pump, I know plenty of people running without it. It is a popular upgrade to get the RS4 controller with the pump

Click to expand...

i think u have a bigger nightmare then i do lol.Hope i don't have this problem once its all back together

I hope not...many think "it's the tune not loaded right", but GIAC says "HuH?". They have been really kind to not shut me out...a total 180° from what DM does.

OK...after clearing all fault codes including the J17 fuel pump relay...I ran data again and the low, high fuel pressure, request still exists. Now I have to run race fuel in race mode in the next day or so bcuz need to empty the tank of pump fuel. If still exists... we reload the DM tune and look.

Have you checked resistance on the fuel pump relay? Have you tried using another relay?

I just got the new relay today and yes, I need to plug it in and try. I will check ohms of the new one first and then compare to the old one coming out. I'll post the results. I did just go through this with boost...discovering that the N75 boost controller was @ 22ohm and, maybe it was you that wrote, it needs to be 25 to 35ohm. But, it did correct the boost acceleration I was lacking

I checked resistance across the two posts marked. The old resistance is 66.7ohm...although it kept jumping around...and then the new relay is 62.3ohm.


I went to VW today asking for a correct fuse and location diagram for my car because the owner manual is worthless. I was given 7 different printouts for varying model years to figure out for myself. None of them fit the amps in regards to where my fuses are...meaning that the amps that are in the actual positions aren't what any of the diagrams say they should be. Two diagrams are close, with only two fuses not matching...then the other five diagrams show 5,6,7, and two with 8 numbers of mismatched amp fuses.

Then, I was told by the parts guy that the J17 is under the hood and I said I thought it was under the driver-side dash. Ask the tech to help...so I did...he said it is under the dash...in the number 4 location of a printout I now had. There is nothing in the number 4 position under there...only have something in numbers 1, 3, and 5...2 and 4 are empty. Got on the phone to demand a proper layout from VWOA...was on hold for over an hour...gave up there. While discovering that nothing under the dash matched this relay...I found a relay under the hood that matched and that is what I tested. Anyhow, yes, the old relay was 66.7 and the new is 62.3...but of course, may not even be the right one or even the fuel pump relay...so the new fuel pump relay sits on the shelf asking "why?".

...anyhow, rant over regarding today's mess...likely be adding the race fuel tomorrow and do the data check Wednesday. Giving up on the fuel relay for now bcuz don't know where it really is. The code isn't there under auto-scan.

You should also energize the 2 posts and then check the resistance of the switch on the relay

Here's a pretty decent vid

https://youtu.be/IpRWcNoLdwQ

That will be helpful...thank you for providing a link....and I will do this and learn what I can before messing with the relay replacement. I'll post what I find when done testing the relay more thoroughly.

OK...I put in race fuel and switched to its mode. Ran data this morning with no change...still requesting 109.9bar. Then went to get what I needed to test the old fuel pump relay(J17) if I find it...stopped at the dealer again and asked "where is it because it is not where you told me it is?". They looked again and then tell me I do not have one...just the controller at the lpfp is showing on the wiring for my VIN. AYFKM?!

So, reported all this to GIAC...now, I am reloading my stock tune when I can get in to Techtonics so I can reload my DM files to test if the pressure request is there too so we can finally determine if it is tune or hardware related. If it is hardware...it looks like I am going to have to wait until it fails completely to locate the cause here.

any luck yet

Nope...going to Techtonics this week on Wednesday to get returned to stock so I can load my DM files to determine if it is the GIAC tune or if it's a stealthy hardware issue.

Just out of curiosity.... What are your low pressures sitting at? Requested/actual. After doing all my low pressure logging I've noticed that depending of what you low pressure is at, will effect how much your high pressure is requesting.

Usually it is at 4bar...sometimes after a data run it will start a bit higher like 5.5 or 5.0bar, but tapers if memory still works. I can look at it again.