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DW65C premature failure


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I have 60k miles on my DW65c, pretty certain it has failed, will tear apart over lunch and try the stock pump. I am slightly modded, never worked the pump, so very surprised to see it take a crap this early. Have others seen premature failure? Just out of my 3 year warranty.
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Makes sense that the regulator is the issue. Is there a place you can install a fuel pressure gauge and the other side of the regulator ?

 

 

http://people.csail.mit.edu/ilh/vacation/

 

That may help.

305,600miles 5/2012 ej257 short block, 8/2011 installed VF52 turbo, @20.8psi, 280whp, 300ftlbs. (SOLD).  CHECK your oil, these cars use it.

 

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With all these failures, do you guys run out of fuel often?

 

Aftermarket fuel pumps, including DW65c, are not pulse modulation happy. OEM tune tries to run the pump at 3 different duty cycles, 33%, 66%, 100%. Aftermarket pumps usually like to run at 100% all the time, which his how most returned system pumps would run too before emissions got stricter.

 

Anyway, when running aftermarket pumps you should update the tune (experimental item in ecu flash) to force the pump to run at 100% all the time.

05 LGT 16G 14psi 290whp/30mpg (SOLD)

12 OBP Stock 130whp/27mpg@87 Oct

00 G20t GT28r 10psi 250whp/36mpg

22 Ascent STOCK

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utc_pyro raised a very good point in that running the stock duty cycle settings of 33% puts the pump voltage below 6v, which Deatschwerks warn against. Can't whine about the pump quality when you're running at under-voltage.
Obligatory '[URL="http://legacygt.com/forums/showthread.php/2008-gh8-238668.html?t=238668"]build thread[/URL]' Increased capacity to 2.7 liters, still turbo, but no longer need spark plugs.
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I have seen a few failures with the DW65c. However, they were all the same batch. The pumps were overheating. DW supposedly fixed the issue. At about the same time they also released the 300c. It is supposed to be taking the place of the 65c. Since the release of the 300c we have not installed a 65c. We have had zero failures (so far) with the 300c.
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With all these failures, do you guys run out of fuel often?

 

Aftermarket fuel pumps, including DW65c, are not pulse modulation happy. OEM tune tries to run the pump at 3 different duty cycles, 33%, 66%, 100%. Aftermarket pumps usually like to run at 100% all the time, which his how most returned system pumps would run too before emissions got stricter.

 

Anyway, when running aftermarket pumps you should update the tune (experimental item in ecu flash) to force the pump to run at 100% all the time.

 

utc_pyro raised a very good point in that running the stock duty cycle settings of 33% puts the pump voltage below 6v, which Deatschwerks warn against. Can't whine about the pump quality when you're running at under-voltage.

 

This is out of my area of familiarity, but I can certainly update the pump Low/Mid/High duty values in my AP-based tune. About 1.5 yrs ago the DW65c that was on my car when I bought it started running out of fuel on the dyno in 4th above ~5500 rpm, although it was able to support a deliberate (for testing purposes) rich dip in 3rd above the same rpm. It was replaced with another DW65c.

 

Any fueling effects expected by either specifying 100% for Low/Mid/High ranges? Any longevity benefit (or detriment) changing Low from 33 to 66%, leaving Mid at 66% (and of course leaving High at 100)?

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This is out of my area of familiarity, but I can certainly update the pump Low/Mid/High duty values in my AP-based tune. About 1.5 yrs ago the DW65c that was on my car when I bought it started running out of fuel on the dyno in 4th above ~5500 rpm, although it was able to support a deliberate (for testing purposes) rich dip in 3rd above the same rpm. It was replaced with another DW65c.

 

Any fueling effects expected by either specifying 100% for Low/Mid/High ranges? Any longevity benefit (or detriment) changing Low from 33 to 66%, leaving Mid at 66% (and of course leaving High at 100)?

 

 

 

I've since updated my tunes to run 45/66/100 instead of 33/66/100. No change in LTFTs so it seems the return system can deal with bumping flow up that little bit. I'm pretty sure the low range is only in use in CL fueling.

Obligatory '[URL="http://legacygt.com/forums/showthread.php/2008-gh8-238668.html?t=238668"]build thread[/URL]' Increased capacity to 2.7 liters, still turbo, but no longer need spark plugs.
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Having pulse width modulation (duty cycles) is a byproduct of a returnless fuel systems, returned systems don't need it. Most return pumps ran at 100% duty cycle for over 100k miles. But 100% duty cycle meant more fuel was being sent to the fuel rail, warmed up by the engine, then sent back to the tank. This created would evaporate the fuel more and create more evaporative emissions.

 

As for when 33% is used, from what I've seen it's only used at very low load, and 66% is used for normal acceleration. I could probably map boost/vacuum to duty cycles form my highway logs to get more precise then that.

05 LGT 16G 14psi 290whp/30mpg (SOLD)

12 OBP Stock 130whp/27mpg@87 Oct

00 G20t GT28r 10psi 250whp/36mpg

22 Ascent STOCK

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I've since updated my tunes to run 45/66/100 instead of 33/66/100. No change in LTFTs so it seems the return system can deal with bumping flow up that little bit. I'm pretty sure the low range is only in use in CL fueling.

 

Having pulse width modulation (duty cycles) is a byproduct of a returned fuel systems, return systems don't need it. Most return pumps ran at 100% duty cycle for over 100k miles. But 100% duty cycle meant more fuel was being sent to the fuel rail, warmed up by the engine, then sent back to the tank. This created would evaporate the fuel more and create more evaporative emissions.

 

As for when 33% is used, from what I've seen it's only used at very low load, and 66% is used for normal acceleration. I could probably map boost/vacuum to duty cycles form my highway logs to get more precise then that.

 

Thanks guys. For now I changed the FP duty to 45/66/100 (vs 33/66/100 originally).

 

Looking at my tune in ATR, the IDC threshold for transition from Low to Mid duty is 10.25 and the threshold for Mid to High is 30.74. Looking at a recent log I took while deliberately running the car through various airflow increments/ranges for CL MAF scaling, I see that when I'm around 69-70 g/sec (right before it switches out of CL), IDC is just cracking 15%. So it seems that for cruise it sits at the Low duty value, light/normal accel puts it into Mid.

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