MK5 Golf GTI
All Things Mk5 => Mk5 General Area => Topic started by: Rob. on November 17, 2014, 07:56:41 am
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After my Stage 2 map, the R-Tech guys pointed out that my HPFP was struggling. Now it's a couple of weeks down the line, the car feels like it's lost all power above 3000 RPM even with my right foot planted (though it's intermittent, and occasionally will come on full boost at random)
Do you guys know what a new HPFP would cost from the dealer (or elsewhere)?
I know about the aftermarket options, I'm just not sure I can warrant spending £400+ :(
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Struggling as in failing, or holding you back? The HPFP is a limiting factor at stage 2.... Get it checked and verified before spending out. To check HPFP log block 230 (i think it's 230) with VCDS under full load and check the actual pressure stays with the specified pressure (within a few bar)
Have you monitored boost levels to see if it's holding the same amount of boost?
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Loads of used HPFPs on eBay for less than £200 last time I looked.
A used APR pump can be had for £350- although not many about. .
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I did some VCDS logging last night, but I missed a few check boxes so will try again later. The car drives fine (or as good as) at low revs, it can barely climb above 3500RPM.
VCDS did show an error for low fuel pressure (and the CEL light came back on briefly, which I've heard can be related?)
Noticed there's a few stock pumps for £100 on eBay, so might have to give that a go, for now at least.
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One thing...my current HPFP has the banjo bolt, so I'm assuming I need to make sure I get the correct revision to match mine?
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This is doing my head right in now :mad:
Bought a used pump from eBay. Swapped all the fittings etc, had it on and running in half an hour.
Went for a test drive, let her warm up, then gave it some full throttle off the motorway slip. Went through all the gears as good as new...then literally 3 miles later, the same problem appears again.
Left it for an hour at the gym, on the drive home gave it some beans in 2nd and 3rd and it was back to normal. Round a roundabout...no power above 3000RPM.
I did some VCDS logging before the change, so will post up the graphs when I get some time to look at the data.
I'm scared of shelling out £150+ for a new OEM pump in case the map is somehow killing them?
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Rob, did your logging show the HPFP not keeping up with requested flow before you changed it ? Is the new one showing the same?
Have you spoken to RTech?
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Please post the logs!
Do you have any stored fault codes as my gut feeling it's either your low fuel pressure sensor (old revision ones are prone to go bad) or your lpfp can't maintain sufficient output pressure...
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Could try the autotech internals? Made a big different when i went stage2+
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Thanks for the suggestions guys :)
Right, this log is with the old pump.
Error code as below:
000135 - Fuel Rail/System Pressure
P0087 - 002 - Too Low - MIL ON
Freeze Frame:
Fault Status: 11100010
Fault Priority: 0
Fault Frequency: 17
Reset counter: 255
Mileage: 128897 km
Time Indication: 0
Date: 2000.00.00
Time: 17:55:42
Freeze Frame:
RPM: 3596 /min
Load: 7.1 %
Speed: 148.0 km/h
Temperature: 83.0∞C
Temperature: 15.0∞C
Absolute Pres.: 980.0 mbar
Voltage: 14.351 V
So logs from VCDS. Rail pressure specified vs actual...looks like it's keeping up, despite the judder. Think this is what R-Tech meant when they said it needed replacing
(https://farm9.staticflickr.com/8660/15823785286_d52419132c_o.jpg)
Then Boost specified vs actual. Foot flat to the floor, shifting up through the gears. You can see the engine speed tapering off as it reaches 3500RPM (I think I downshifted to try and get some life out of it, hence the 4500RPM spike)
I don't get this: why is the actual always a lot higher than specified? Looks dodgy.
(https://farm9.staticflickr.com/8601/15847621291_32d721dc44_o.jpg)
I'm gonna swap the Rev D DV out for a Rev G on R-Techs advice.
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Just give it back to R-Tech to straighten out.
I've not used them myself, but I'm surprised you got the car back at stage 2 with the advice that your pump may not keep up without it being resolved. I should have thought (unless it was your choice) that it was a prerequisite for your chosen tuning package. Stage 2 starts to require certain pieces of hardware and this where you run into certain opinions about what is and what isn't required. Get it right and your car will runs as hard as you like for as long as you like. If you leave the wrong hardware in place you can end up on a knife edge where depending on component tolerance & wear you may or may not get away with it.
Not saying anyone got it wrong, just get it back to the right people to fix. You'll enjoy your car sooner and protect your investment. :happy2:
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It sounds like when you had it mapped it was working but not as well as it should, Niki would have de-tuned it slightly to take that into account. Sounds like over the last 2 weeks it's deteriorated further and that's why the fuel cuts have appeared 2 weeks after mapping but the car drove fine for the first 2 weeks.
As I said further up my post, there are loads of HPFPs on eBay and thankfully it's an easy (although not cheap) fix :happy2:
I disagree with @flashp (http://www.mk5golfgti.co.uk/forum/index.php?action=profile;u=5579) as de-tuning it isn't the solution here as the HPFP is on a downward spiral, de-tuning will fix it for a few weeks before it just deteriorates to the point it starts to fail again.
Just drive gently until it's fixed :happy2:
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It sounds like when you had it mapped it was working but not as well as it should, Niki would have de-tuned it slightly to take that into account. Sounds like over the last 2 weeks it's deteriorated further and that's why the fuel cuts have appeared 2 weeks after mapping but the car drove fine for the first 2 weeks.
As I said further up my post, there are loads of HPFPs on eBay and thankfully it's an easy (although not cheap) fix :happy2:
I disagree with @flashp (http://www.mk5golfgti.co.uk/forum/index.php?action=profile;u=5579) as de-tuning it isn't the solution here as the HPFP is on a downward spiral, de-tuning will fix it for a few weeks before it just deteriorates to the point it starts to fail again.
Just drive gently until it's fixed :happy2:
I haven't suggested it be de-tuned.
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It sounds like when you had it mapped it was working but not as well as it should, Niki would have de-tuned it slightly to take that into account. Sounds like over the last 2 weeks it's deteriorated further and that's why the fuel cuts have appeared 2 weeks after mapping but the car drove fine for the first 2 weeks.
As I said further up my post, there are loads of HPFPs on eBay and thankfully it's an easy (although not cheap) fix :happy2:
I disagree with @flashp (http://www.mk5golfgti.co.uk/forum/index.php?action=profile;u=5579) as de-tuning it isn't the solution here as the HPFP is on a downward spiral, de-tuning will fix it for a few weeks before it just deteriorates to the point it starts to fail again.
Just drive gently until it's fixed :happy2:
Obviously the disclaimer is that remaps can highlight weaknesses in other areas...I'm fine with all that :) But I really want to find out what it is so I can fix it. Niki did say the current pump wanted replacing, and that he was working around it.
So I've replaced the fuel pump with a newer revision (think it's a H, up from an F) but the same problem appeared within a few minutes...so unless the remap is actually killing the fuel pumps, I figure it must be something else causing the loss of power?
The actual fuel pressures on my graph aren't falling way short (other than the "Actual" wavering either side of the "Requested" a bit)
Stage 2 doesn't require an uprated pump (though it's obviously beneficial)
Could a leaking DV cause this much of an obvious issue?
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So I'm still getting an intermittent loss of power with the changed (albeit still used) pump.
This is the Actual vs Specified for the rail pressures...look pretty similar to the old pump (maybe a bit less spikey?)
(https://farm8.staticflickr.com/7465/15273494533_391f961e2a_o.jpg)
Even though the car is logging a fault, could it be something else that's causing the power loss?
I'm still on the Rev D DV. Surely that couldn't make this much of an issue...could it?
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I'm no expert, but it looks like the pump is holding out fine, it's meeting its targets as far as I can see :confused:
Have you done any other logs?
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Yeh, I recorded all the blocks outlined in the APR data logging page, so can post up whatever people think will be useful
I'm stumped by the boost logs I posted earlier...the Actual is well above the Specified.
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What does Rtech say?
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This may sound daft - but have you replaced your cam follower?
Looking at your logs, you need to find a straight stretch of bypass and do a full run through 3rd gear right through the rev range, as easing off and changing gear may be hiding the issue.
R-Tech are very helpful for troubleshooting, I had low pressure fuelling issues with my old K03 GTI and R-Tech altered the boost delivery to remove the issue
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I spoke to Ben a couple of days ago, but he hadn't had a chance to speak to Niki.
One downside of making a point of going to the best people in the business...is that they're 3hrs+ drive away from me! So I can't just pop round to speak to them.
Cam follower is fine - replaced it myself a few months ago, and inspected it again when I changed the fuel pump last week
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I spoke to Ben a couple of days ago, but he hadn't had a chance to speak to Niki.
One downside of making a point of going to the best people in the business...is that they're 3hrs+ drive away from me! So I can't just pop round to speak to them.
Cam follower is fine - replaced it myself a few months ago, and inspected it again when I changed the fuel pump last week
Ah right ok.
If you can get some decent 3rd gear logs (following APRs guidelines) you can email them to Niki and he will tell you whats wrong.
If you are on facebook, join the "TFSI Tuning" group, its run by Niki and full of enthusiasts (loads of us from here on it). You can post your logs there and get suggestions :happy2:
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Here is something I overlooked before
http://wiki.ross-tech.com/wiki/index.php/16471/P0087/000135
I also had a reply from R-Tech outlining similar things, so I'm going to replace the fuel filter and see what I can find out about the G410 low pressure sensor too.
I replaced the cam follower at 70k, and the current one still looks spot on at 80k, so hoping the cam side of things isn't the issue.
Then I suppose if none of that works, I'll have to shell out for an uprated HPFP
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When replacing the fuel filter, make sure you get the 6.6BAR filter rather than the 6.4BAR one :happy2:
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This look more like a boast problem then a HPFP problem, I had the same thing happen to me on my 1.8T, turned out to be the N75 Valve, but the worst part about the problem was the valve did not trigger any error codes in VCDS, and was the last thing that got replaced.
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This look more like a boast problem then a HPFP problem, I had the same thing happen to me on my 1.8T, turned out to be the N75 Valve, but the worst part about the problem was the valve did not trigger any error codes in VCDS, and was the last thing that got replaced.
The fault code he has is a fuel pressure related code though? :surprised:
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I've got a new 6.6bar fuel filter arriving tomorrow, so hopefully fit that this weekend. Might try TPS and see if I can get a G401 sensor too.
I took her for a spin yesterday...and the logs basically contradict the others I posted previously :scared:
This is a 3rd gear pull, and it pulled hard right up to 6000rpm or so, then it felt like it hit a wall. You can see my full throttle input, yet the revs are dropping past 5000rpm. The rail pressure actual/specified difference increases past 3500rpm, yet the car still pulled hard...then after it broke, the rail pressures look evenly matched?!
(https://farm9.staticflickr.com/8604/15759845430_4fa1ff62af_o.jpg)
This is a 4th gear pull a couple of minutes later. Foot nearly flat, but a huge difference in actual/specified rail pressure
(https://farm8.staticflickr.com/7485/15759845670_f2b571375c_b.jpg)
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Your logs are poor as youve let off the throttle, these logs only really work well if you keep your foot planted to the floor for the whole run.
The rail pressure request will be written into the map to maintain 120 bar from 3/4 load (or something like that).
See if the fuel filter makes a difference, then move onto the pressure sensor. There are loads of HPFPs on Ebay, it may be easier to just get one of those. . .