Fuel System Issues, Looking For Ideas/Input - Performance Forum

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Fuel System Issues, Looking For Ideas/Input
Monday, July 01, 2013 11:41 AM
Ryan did his best this weekend to try to get me tuned while I was down helping Brandon as best I could but we ran into some issues.

Started out by working on the idle... He got it to idle and it sounded great. Finally got to get the car on the road and take it for a spin for once. Only put maybe a mile or two on it but it was good to be back in it after 3 years of down time. During the test drive, I could accelerate slowly and be ok. As soon as I touched into boost, went instant lean. Drove back to the shop to see what was up. Worked on the idle some more and it kept going super lean during idle. So lean that when I touched the gas it would stall. Bumped the pressure up to 68-70 to see if it would make it rich... didn't work. Didn't have a clue why.

Got the car on the lift, dropped the tank to check all the lines on the Racetronix pump... They were all still attached and in what looked like great working condition. Put tank back in, pulled the line off the fuel rail and jumper wired the pump on.... pumped decent fuel for about 20-30 seconds and then it was sputter out fuel in almost pulses. Like it was sucking air and fuel at the same time.

Dropped the tank again... this time we cut the cup to be sure fuel was getting in and thought the venturi may not be working anymore. I don't know. Put the tank back in, jumped the pump again, and it was flowing decent. No more sputtering, just decent flow. Put the fuel line back on the rail, fire the car up... 14.0-14.8, then 15.xx, 17.xx, - - -, which for those with an aem means its 18.0 or leaner. Ryan is also questioning injectors. 60-70 base fuel pressure, and 124% idle VE finally netted an 13-15 afr.

He even put my 440cc tune on the car and it ran the same as if it had the 750's on it so it seemed. So the questions come up, are the injectors correct? Is the pump not pushing enough pressure or volume? We don't think my lines are too small since they are factory lines, and Ryan, even though is is an LN2, is on stock lines, and Brandon made a ton of power on stock lines as well.

Leads me to the next part... Car is back in the garage in storage again until I come up with some sort of a plan or idea. Either I go aluminum fuel cell, external pump, all new lines rear to front.... or find a way to narrow it down to injectors, or I toss a helper pump inline with the racetronix... or I replace the racetronix I have... so I have options, I am just frustrated at the moment with it.

Luckily my fiance was very understanding and said that we both have jobs that can support a hobby like mine so she wants me to keep it... against my better judgement. I know I want to see it run, as well as Brandon and Ryan do. Even Ryan was telling me to chill, relax and take a step back and we will figure it out... it can only be so many things.

I can't thank Brandon and Ryan enough. They both helped dive right into tearing the tank down many a times to diagnose it. If it wasn't for being at Brandon's shop, we probably couldn't have narrowed it down as far as we did. im glad we did though. They stayed up til 2:30am helping me in hopes we could get it.

Was a no go in the end and I loaded up and trucked back up north with it. Pricing out the pump/cell/lines now just to see what im looking at for prices before I decide what im going to try to do to fix the issues. I just dont know where to start. Ryan tossed out the idea of a booster pump because it might be getting enough pressure, just not enough volume. Which is why it starts out idling normal then creeps up to lean.

So, I am open to all suggestions im all ears. I might get some measurements and see if I can borrow some injectors to see if thats the issue. Going to call the place I got my injectors from once I get the numbers off them again... odds are it wont be for a few weeks unless I call my parents house where the car is stored and get them off again.




Re: Fuel System Issues, Looking For Ideas/Input
Monday, July 01, 2013 1:06 PM
Being you are having the problem at idle, the racetronix is more than enough to support idle fueling. So if a booster pump fixed it at idle that just tells me your have a bad pump.

I recommend going to a AFPR and fuel pump change. If it was just n the higher rpms I would say a booster pump would be the easy fit.



FU Tuning



Re: Fuel System Issues, Looking For Ideas/Input
Monday, July 01, 2013 1:27 PM
I am thinking it is the pump that has gave up on you.

I believe chris miller had a fuel cell and external pump setup for sale if you want to go that direction. Or look into the 600 hp Racetronix pump
Re: Fuel System Issues, Looking For Ideas/Input
Monday, July 01, 2013 1:33 PM
I can adjust fuel pressure via the FMU I have... Thats how we raised the pressure at idle. My gauge was showing 68-70psi... Ryan seemed to think the volume was down which is why a booster pump was a thought. Seems if I go fuel cell with sump, it eliminates all the problems all together... but IDK....



Re: Fuel System Issues, Looking For Ideas/Input
Monday, July 01, 2013 1:38 PM
Philly D wrote:I am thinking it is the pump that has gave up on you.

I believe chris miller had a fuel cell and external pump setup for sale if you want to go that direction. Or look into the 600 hp Racetronix pump


x2

If you wanted to upgrade, that'd be a good solution. Have you tried it without the sock on the pump? I've heard others having trouble with the sock being defective/too restrictive. What regulator are you using to adjust the pressure?

You should also know that my 440cc injectors with the same 60-70psi base fuel pressure is causing idle problems because the injectors can't support such a small pulse width. Meaning, with even bigger injectors you may see the same problems (some do, some don't).

EDIT: Just saw that you posted while I was typing. Don't have much experience with FMUs but I can't imagine that would be the problem. That adds pressure with boost reference as well right?


Edited 1 time(s). Last edited Monday, July 01, 2013 1:42 PM


"In Oldskool we trust"
Re: Fuel System Issues, Looking For Ideas/Input
Monday, July 01, 2013 2:12 PM
BuiltNBoosted wrote:I can adjust fuel pressure via the FMU I have... Thats how we raised the pressure at idle. My gauge was showing 68-70psi... Ryan seemed to think the volume was down which is why a booster pump was a thought. Seems if I go fuel cell with sump, it eliminates all the problems all together... but IDK....


Ryan and I have talked about your car.

If the fuel system is up to the task the FMU is not needed.

No reason to need a booster pump to get idle fueling correct. He has never seen this nor have I.

I really do think it is your pump. To me a new intake racetronix is the way to go, but if you want to upgrade to a race cell and pump that is your call.



FU Tuning



Re: Fuel System Issues, Looking For Ideas/Input
Monday, July 01, 2013 2:14 PM
Let me also add. I have seen times when the racetronix could not keep up, but that was on a car with upgrade fuel lines from the tank to the rail. It could not keep pressure. A booster pump was the fix, but the only time the problem showed it's self was under full boost.



FU Tuning



Re: Fuel System Issues, Looking For Ideas/Input
Monday, July 01, 2013 2:26 PM
This may be related.

I just changed my stock pump out for a Racetronix this weekend. My symptoms were a little high afr on the GM reflash and always getting knock. I checked the pumps pressure and was always just fine. I slapped the Racetronix in and the knock is now gone and my afr's are more where they should be according to other people with the reflash. So the pump was obviously not able to keep up to the demand and was worn out.

I had the same issue with my streetbike. Bike ran just fine but when you got on it and the secondary injectors came on it would buck and pulse.

Cheapest option is to just get a new Racetronix. With your setup id probably opt for the pump Jucnboost posted being a 600hp pump since the Racetronix is apparently only good for 400.
Re: Fuel System Issues, Looking For Ideas/Input
Monday, July 01, 2013 3:14 PM
Is there anything else out there besides racetronix? I know I have heard mention of the aeromotive stealth series but see mixed reviews on them... I read bad about Racetronix's customer service, someone else mentioned fuel labs.... I would much rather do a drop in again than a whole cell and lines obviously. Also, need to check and make sure I have a spare pump assembly back home so I dont have to use the cut up fuel cup. Not that it would be all that terrible to use, but id prefer the full cup.



Re: Fuel System Issues, Looking For Ideas/Input
Monday, July 01, 2013 3:15 PM
bad oil pressure sender?



M45/OS crank/2.4 snout. It's nice to be injected but I love being blown!
Re: Fuel System Issues, Looking For Ideas/Input
Monday, July 01, 2013 3:25 PM
you mean fuel pressure? and no its a gauge itself... no senders.




Re: Fuel System Issues, Looking For Ideas/Input
Monday, July 01, 2013 4:03 PM
BuiltNBoosted wrote:Is there anything else out there besides racetronix? I know I have heard mention of the aeromotive stealth series but see mixed reviews on them... I read bad about Racetronix's customer service, someone else mentioned fuel labs.... I would much rather do a drop in again than a whole cell and lines obviously. Also, need to check and make sure I have a spare pump assembly back home so I dont have to use the cut up fuel cup. Not that it would be all that terrible to use, but id prefer the full cup.


For a drop in you are some what limited. Racetronix is just a Walbro so you could get a walbro pump.

I have never heard of bad customer service from Racetronix.

If you go fuel cell then your options majorly change.



FU Tuning



Re: Fuel System Issues, Looking For Ideas/Input
Monday, July 01, 2013 4:15 PM
I have actually read alot of bad about them on other forums.

My personal experiences were not that great either. The guy on the other end of the phone was very argumentative. I asked them to ship via Canada Post since im in Canada and hate UPS. The guy asked me multiple times why I cant just ship UPS, why I don't want to go with them etc. After explaining I live far from them and its very hard for me to actually receive whatever im buying so id rather go Canada post which is closer to me. He then shipped it through UPS anyways and when I called him he didn't care. Basically told me to f off.

The general thing I read about them on the other forums is there is zero customer service.

Ill buy from them if I have to replace my pump, but I know I wont be happy about it.
Re: Fuel System Issues, Looking For Ideas/Input
Monday, July 01, 2013 4:25 PM
I hear to never order from them directly... go through a vendor and you get a better experience. They dont have any phone number what so ever on the site. I hear a lot of bad instances where like above, they treat their customers really rude. The person i am emailing is not being very clear or helping much either. I asked if they test pumps if I send them one. All he said was Jet pump may be plugged. Time for a new module. We do not have pumps to support new modules. WTF does that mean?

I never had an issue really until now so Im not sure what to do just yet.



Re: Fuel System Issues, Looking For Ideas/Input
Monday, July 01, 2013 4:37 PM
They wouldn't even respond to my emails lol. With not supporting new modules im sure he is meaning the newer cars?

Here is their number though.

905-477-7014
Re: Fuel System Issues, Looking For Ideas/Input
Monday, July 01, 2013 6:25 PM
Im not even going to waste my time calling.

Might just buy a pump and see what happens.



Re: Fuel System Issues, Looking For Ideas/Input
Monday, July 01, 2013 8:58 PM
BuiltNBoosted wrote:you mean fuel pressure? and no its a gauge itself... no senders.


no, i actually mean the oil pressure sender. aka the idiot light. on gm cars they set it up so if the car rolls over and engine loses oil pressure it kills the fuel pump. or at least thats what i have read anyway... not saying thats your problem but it might be a good idea to swap out the sender since its cheap. it may be malfunctioning.



M45/OS crank/2.4 snout. It's nice to be injected but I love being blown!
Re: Fuel System Issues, Looking For Ideas/Input
Tuesday, July 02, 2013 4:07 AM
By new modules he maybe meant that the pump only works with the stock gm sending unit as opposed to a parts store replacement. Either way it's strange that they have no phone number. Hopefully a new pump solves your problem..



"In Oldskool we trust"
Re: Fuel System Issues, Looking For Ideas/Input
Tuesday, July 02, 2013 4:39 AM
-Z Yaaaa- wrote:
BuiltNBoosted wrote:you mean fuel pressure? and no its a gauge itself... no senders.


no, i actually mean the oil pressure sender. aka the idiot light. on gm cars they set it up so if the car rolls over and engine loses oil pressure it kills the fuel pump. or at least thats what i have read anyway... not saying thats your problem but it might be a good idea to swap out the sender since its cheap. it may be malfunctioning.


my oil pressure sender wire is cut and dangling. my car still runs fine, fuel pressure is nice and high.

vince, the bottom line is if your fuel pressure is low at idle, the pump is bad.

did you check to make sure the feed hose from the pump to the top of the cup is not split or KINKED? that could be a serious problem.

I replaced my feed hose with a 300psi air hose and I build pressure like nobody's business now. gonna drop in Gates 30r10 hose next time I drop the tank.






Re: Fuel System Issues, Looking For Ideas/Input
Tuesday, July 02, 2013 11:49 AM
we checked, re-checked and double checked the lines. looks like i need to do some pump shopping...



Re: Fuel System Issues, Looking For Ideas/Input
Tuesday, July 02, 2013 1:21 PM
DaFlyinSkwirl (Pj) wrote:
-Z Yaaaa- wrote:
BuiltNBoosted wrote:you mean fuel pressure? and no its a gauge itself... no senders.


no, i actually mean the oil pressure sender. aka the idiot light. on gm cars they set it up so if the car rolls over and engine loses oil pressure it kills the fuel pump. or at least thats what i have read anyway... not saying thats your problem but it might be a good idea to swap out the sender since its cheap. it may be malfunctioning.


my oil pressure sender wire is cut and dangling. my car still runs fine, fuel pressure is nice and high.

vince, the bottom line is if your fuel pressure is low at idle, the pump is bad.



Exactly.



FU Tuning




Re: Fuel System Issues, Looking For Ideas/Input
Tuesday, July 02, 2013 3:42 PM
DaFlyinSkwirl (Pj) wrote:
-Z Yaaaa- wrote:
BuiltNBoosted wrote:you mean fuel pressure? and no its a gauge itself... no senders.


no, i actually mean the oil pressure sender. aka the idiot light. on gm cars they set it up so if the car rolls over and engine loses oil pressure it kills the fuel pump. or at least thats what i have read anyway... not saying thats your problem but it might be a good idea to swap out the sender since its cheap. it may be malfunctioning.


my oil pressure sender wire is cut and dangling. my car still runs fine, fuel pressure is nice and high.


The switch closes to ground and trips the light when theres no oil pressure. Its always an open circuit when you have pressure. Of course you dont have a problem.



Re: Fuel System Issues, Looking For Ideas/Input
Tuesday, July 02, 2013 4:47 PM
talked to Lonnie at Lonnies Performance in PA and he didnt think a new pump would solve my issues...so im wondering if I need to test some other injectors or pump still.



Re: Fuel System Issues, Looking For Ideas/Input
Tuesday, July 02, 2013 5:13 PM
Did you pick up the injectors new? Might want to get them cleaned before the new pump goes in.




Re: Fuel System Issues, Looking For Ideas/Input
Tuesday, July 02, 2013 5:59 PM
Yes I did. Brand spanking new. I have the papers that came with them somewhere. Flowmatched and all. I need to get the numbers off the side of them again and call the company I bought them from.



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