My head hurts...fuel issues AGAIN!

[Calan]

Finally got the rebuilt HX40 reinstalled tonight and did a few pulls. This is on E85 with a new Deatschwerks fuel pump running at 37psi base.

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For some reason, I'm leaning out like crazy up top, yet BoostEst vs. actual boost ("MAP" in the log) at peak VE shows that I should pull even more fuel. Injector duty cycles are also topping out now, even though they are the same 1250's that I ran before and the IDC's were fine. (I was planning on raising the base pressure to 43psi to help stretch the injectors a bit, but that won't fix whatever is going on right now.)

Airflow shows about 54 lbs/min max, but HP estimates and the butt dyno don't back that up.

I need to do a BLT, but it held 25 psi for over a minute just before I pulled the turbo, and nothing was touched on the piping except the lower IC connection which is an o-ringed V-band clamp. (Besides, I'm running a GM blow-through setup).

Other than the rebuilt HX40, the only thing that has changed is the Deatschwerks pump, which should flow quite a bit more than the wally 255 it replaced.

I think the WB is fine, based on what it reads at other boost levels and at stoich. I'm using NB simulation, and the tune is dead on during off-boost. I used all new copper exhaust gaskets, but I'll seafoam it later this morning and see if any leaks show up.

It's gotta be something simple, but I'll be damned if I can see it right now. Maybe I just need sleep.

Ideas?

 

[DJ23GSX]

I had an issue similar to this on my old dsm. It ended up being a few problems for me. The first problem was that the bolts on the top of my aeromotive afpr that hold the cap down on the diaphragm started to back out and it wasn't raising fp at 1:1 ratio under boost causing me to lean out in the upper rpm's. After I fixed that all was good for a couple weeks then it started again and that turned out to be a tear in the diaphragm of my aeromotive afpr. Again after fixing that problem all was good for a few weeks then low and behold it started again. This time it ended up being my walbro 255 was on its way out and couldn't provide enough fuel under high boost. I put a new walbro 255 in and the problem was fixed for good. I'm not familiar with the Deatschwerks pump but if it still uses the o-ring to connect to the sending unit make sure its not torn or crinkled up and leaking fuel back into the tank.

Since you already have the walbro it wouldn't hurt to try and toss it back in and see if the problem still exist. Did you buy the Deatschwerks pump new or used?

 

[delta448]

Looks like an AFPR issue to me.

 

[Calan]

DJ23GSX - It's a new pump and uses a piece of rubber hose to connect to the hangar; o-ring is gone.

Zack - Could be I guess. I get a fluttering noise from it sometimes at idle. I need to get a fuel pressure sensor hooked up so I can log it.

I still don't get why BoostEst vs. actual boost says I need to pull 9.5% more fuel when the AFR shows lean, unless I'm losing a crapload of fuel up top.

 

[rlacasse1]

I thought that pump that you are using actually flowed less at high pressure than a 255 did. Correct me if I'm wrong. I saw the graph for it, or maybe I'm confusing it.

 

[Calan]

No, it flows considerably more... or so I was told by the guys at Deatschwerks (they are local).

 

[Calan]

Here's a new log, with a fuel pressure sender installed. I am definitely loosing fuel pressure; about 12psi worth at 20psi of boost.

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EDIT:

Did some more testing, and found a few things:

1. The injectors had quite a bit of "E85 goo" buildup. I don't think that could account for the fuel pressure drop though. If anything, I would think pressure would be higher if the injectors were restricting the expected increase in flow as rpm's increase.

2. Took apart the fuel filter and it's clean.

3. The AFPR looks good. No pin holes in the diaphram, and fuel pressure rises 1 to 1 on a static test with up to 40 psi input to the AFPR with the base at 43. No leakage into the fuel from air, and no fuel leaking into the air chamber. Also no leaks in any lines that I can find.

4. Voltage at the fuel pump was 12v with the engine off (same as battery voltage reported by ECMLink), and dropped to 11.5v when we turned the pump on. So it should be seeing about 13.3v with the car running, assuming a .5v drop across the pump (which seems reasonable).

5. Did a flow test on the fuel pump. At 80psi, I measured only 106 lph out of the AFPR return port (1.4 gallons in 3 minutes = 106 lph). At 13.4v it should be flowing 230 lph according to Deatschwerks, but there is no data for 12v...still seems really low though even at the lower voltage. Is that a good test for the flow rate, or is the AFPR more restrictive than the method used to generate the advertised flow rates? I don't know how else it would be tested, but maybe I'm missing something obvious.

So, I have dropping fuel pressure that seems to be related to rpmidontknow, and a pump that is apparently flowing way less than it should. This leads me back to believing it is a fuel pump issue, but this is a brand new pump from a different manufacturer, and the third one to exhibit signs of leaning out...although this one is doing it at much lower boost. The other thing that seems strange is that the pump is perfectly capable of maintaining 80 psi in a static test with the engine off (even though the flow rate seems low). As you can see in the log, the pump holds 1 to 1 pressure at 20 psi for a bit, and then starts dropping off around 4800 rpms. Since it can hold that psi for a while, I would expect it to flatline rather than drop if anything, since the boost stays at 20 psi and the only thing changing is injector pulse width as rpm's increase....unless the pump really just can't keep up with the flow demand. But a 300lph pump at only 20psi?

Something still isn't adding up. I'm going to swap one of the wally's back in tomorrow and see what kind of flow it gives me under these same conditions. In the meantime, any other ideas?

*****

BTW - Special thanks to Brian (19Eclipse90) for helping me out, and for keeping me from loading a rifle and searching for a tower. .

 

[delta448]

Very nice to be able to see the fuel pressure in the second log, thanks.

Is your pump rewired? If so, what gauge wire? Grounded where?

If the issue truly is rpm dependant, I'd start looking at the charging system. Also, the current draw from the pump will increase substantially as output pressure increases.

How about restrictions in the fuel path to the rail? Line kinks, clogged filter, etc. When you're seeing 80psi at the rail, the pump could actually be seeing much more...

 

[ziggo0]

Even with a drop from 13.4 to 12v your flow should still be much higher than 106 lph, loss should only be 15%, maybe 20%. How did you test the fuel pump? Did you test at the rail? Judging by your profile your still using stock lines...perhaps there is a damaged section? I know they like to rust, when I pulled my fuel canister for my Walbro 255 installation one of those lines coming out for feed bent because it was so rusted. It could also be a damaged line somewhere inbetween...something else, a custom fuel filter - the lines that go up to it would be another spot to check. Other than that your fuel pump may be a questionable unit (even though it's proven to be good). I think your on the right track.

Edit: Delta448 - didn't see the last line of your post - I agree.

Edit 2: Taking a look around at your fuel filter - a lot of people seem to agree it really damages your flow numbers.

 

[Calan]

I checked all the lines when I rebuilt the car, and everything looks good. The filter is a Golan (large) that flows 900gph, so there is definitely no restriction there. -6AN from the filter to the rail, rail to AFPR, and AFPR to stock return hard line below the brake booster.

Zack - Pump is rewired; I want to say it's 14ga that I used. Wiring and charging system should be fine...I didn't feel any heat in the wires while running the pump at 80psi and I have no other electrical issues at all (I'm running an Optima red top BTW). The logs show a constant 13.8v during WOT.

 

[19Eclipse90]

So I've been thinking about this all day and decided to run some numbers because of what Zach mentioned above. If the pump was only receiving 11.5V (as it was when testing with ECMLink), at 80psi it would still flow more than 106 lph (near 175 lph actually, based and interpolated on linearity at higher voltages via DW's site); at 11.5V, the fuel pressure would have to be in excess of 100psi to flow 106 lph which is impossible for this particular pump, if I understand it right.

Along the same lines, the pump should only require around 9V to pump around 107 lph at 80psi. To me, this suggests that there isn't enough voltage getting to the pump somehow but really I'm just tossing around ideas that might spur something else. Or maybe we somehow measured flow incorrectly...

Did you get to swapping the pumps and doing anything with that?

 

[Calan]

Just pulled back into the garage actually...and it looks like the new Deatschwerks pump is the problem after all.

I punched the pressure relief valve on one of the old Walbro's I had and swapped them out. Here's a new log:

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Fuel pressure matches boost 1 to 1 almost perfectly now (within the margin of error of the assigned sensor properties anyway).

So, I'm back at the mercy of the Walbro running out at higher airflow, but at least I can put a tune on it now. I'm going over to Deatschwerks tomorrow and see what they have to say about it.

I'll see if I can't get BoostEst and MAP to line up better over the next day or two; hopefully I can still keep AFR's on target at the same time. Need to fix that lean area during spool-up also. .

 

[TurboAnything]

I said it before and i will say it again. The GOLAN filter is pure crap!! I am not the only person who has had problems with it not flowing enough fuel. Keep swapping pumps and trying everything but ditching that shitty filter .

Just for reference I had the same filter and could not get even get 40lbs/min out of it without leaning out. I removed the filter element and have never leaned out again.

That is a pic of another DSMer that had the same issue. See how the pressure built up on the back side the pushed the element inside out.

 

[Calan]

I said it before and i will say it again. The GOLAN filter is pure crap!! I am not the only person who has had problems with it not flowing enough fuel.

And I'll say it again (as I did up there ^).

I took the filter apart, and it was perfectly clean; so it should still be capable of flowing it's rated 900gph. And if you read the post just before yours, you'll see that swapping the fuel pumps fixed the drop in pressure.

I have no doubt that some people have had issues with the Golan filter for some reason; but there are also a lot of people running them with no issues at all. If I become one of the casualties of a Golan failure, I'll deal with it then. But for now, the filter is not my problem.

I will however, keep that in mind and do some more testing if a new replacement Deatschwerks pump doesn't fix this once and for all. I'm open to any possibilities and need this fuel issue completely gone.

 

[Calan]

@TurboAnything... I may have to man up and admit you're right.

But I still have something else to check (and the pump(s) are definitely not up to par either).

 

[TurboAnything]

AMS did some testing on the 2 new pumps the Deatchwerks and Aeromotive intank and found that the Aeromotive out flowed the Deatchwerks pump at every pressure. Food for thought but the Deatchwerks pump should still do what you want it to do.

Also i emailed and called Golan on this issue and they told me i am wrong and showed me a pick of their filter on a 1000hp big block chevy with a carb setup i tried to explain about the fact we run 70+psi and that 1000hp carb only runs 7-10psi and the guy told me he does not care and i am still wrong.

In the end i just figured If they do not care then that says a lot about how they run there company and manufacture their products and i am not going to waste any more time trying to help them make a better product.

 

[Calan]

It looks like my issue is a combination of things.

First, to address John's point on the Golan filter... My filter element did in fact have some buildup that was not visible, and only became apparent when I did some shade-tree flow testing on it and let it sit in MCCC and gasoline for a few hours. Removing the element completely as a test obviously increased flow and pressure, but I would expect this anyway, even with a brand new element. Still, it was definitely causing some amount of flow restriction. John was right, I was wrong.... damn it.

The real question is how much of a filter restriction is too much? Every filter has to impose some sort of restriction, but I can't find anyone who has actually measured it on a new OEM (or better) filter to find out how much is "normal". As for the Golan, I'll stand by my opinion that they are fantastic filters for some people (assuming you keep the element clean), but others have had issues with them. As another known example, a local buddy of mine has made well over 500whp and has run numerous 10-second passes on the same Golan filter for years now...and he's never even cleaned the element as far as he can remember.

BUT... the element is susceptible to clogging with no visible indications, so it bears watching.

Second... I got a call from Deatschwerks, and out of 2000+ of these pumps sold, they have only seen 3 issues; guess who #3 was? As it turns out, the PRV was opening too soon, allowing pressure to bleed off earlier than it should. With the margin of error in my pressure gauge and their testing equipment for that particular test, we were easily well into the range that I was seeing the pressure and flow problem.

With that said, I will go on record and say that Deatschwerks has some of the best customer service I've ever encountered. Those guys don't know me from anyone, yet the owner has called me twice to keep me informed of what's going on, and was personally involved in testing the pump and figuring out the issue. They even offered to assist in testing any other part of my fuel setup if it turned out to not be the pump, before I even got it to them. In the end, he has a brand new pump waiting for me to pick up no questions asked and was very honest and forgiving about the whole thing. Fantastic.

So, as seems to be the case with everything on these cars, it was a combination of several things adding up to create one hard-to-find issue; a partially clogged yet innocent looking filter element, two pumps that were at their limit or possibly a little past it, and a brand new pump that had a PRV issue.

My next step is to swap the DW pump back in, and either replace the filter element in the Golan or possibly look for another alternative if funds allow it.

 

[delta448]

I'm glad you figured it out, but if you ever do find yourself looking for a tower again... let's just say, I'll save you a seat, and I'm willing to trade a couple cold Millers and some jerky if you bring me an extra box of ballistic tips.

 

[Calan]

I'm glad you figured it out, but if you ever do find yourself looking for a tower again... let's just say, I'll save you a seat, and I'm willing to trade a couple cold Millers and some jerky if you bring me an extra box of ballistic tips.

How about some Bud Select 55's? I'm watching my girlish figure, and will need to look good for the TV interviews while on death row.

 

[-red97rum-]

I said it before and i will say it again. The GOLAN filter is pure crap!! I am not the only person who has had problems with it not flowing enough fuel. Keep swapping pumps and trying everything but ditching that shitty filter .

Just for reference I had the same filter and could not get even get 40lbs/min out of it without leaning out. I removed the filter element and have never leaned out again.

That is a pic of another DSMer that had the same issue. See how the pressure built up on the back side the pushed the element inside out.

Just checked my golan filter this weekend and I was experiencing the same damn thing! It almost looks as if the fuel pressure was pushing the filter element through the damn housing. Bullshit too because this filter doesn't even have more than 3000 miles on it.

*Edit: Overpriced piece of shit.

 

[boosting_laser]

Hello, my name is boosting_laser & I'm a Golan fuel filter owner.

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