Stock FPR Problems: Who else...

stylEmon · 09-30-2008, 03:39 PM

Has anyone had problems with the stock FPR? I am curious because I am having issues with Fuel Pressure. I have an new filter, new lines from filter to rails, stock rails, 1600cc Bocsh secondaries, no pulsation dampener and stock fpr. (Walbro Hi Flow pump)

I noticed pressure issues, and took off the stock fpr. Replaced it with another stock one and am having the same issue. It's possible that both fpr's are faulty. I would even say it's probable.

Anyone have any insight or similar problems?
Obviously I want to upgrade to an Aeromotive with braided lines and AN fittings, but I don't want to spend the $600 on that right now..
Thanks

Ender · 09-30-2008, 06:04 PM

I don't have any personal experience with something quite like your situation, but I suspect you could have fuel flow issues when two of your injectors are rated for ~3 times the flow of the stock injectors. Are you seeing the pressure drop under light load or just when you're under boost? More specifics would probably help.

stylEmon · 09-30-2008, 07:15 PM

not sure why that would be a problem. I have a stand alone.

The main problem is at idle. The fuel pressure is 20 psi higher than it should be. Under load it raises a little more.

classicauto · 10-01-2008, 07:35 AM

Hmmm.

When did you first noticce the issue? Anything else changed/going on in that time period?

TehMonkay · 10-01-2008, 03:26 PM

It's either not bypassing enough fuel or there's a clog in the line or your fuel tank is very pressurized.

stylEmon · 10-01-2008, 04:42 PM

I think its always been a problem since I had this car running after the engine build.
It was masked by other problems, or unfinished tuning... make sense?

So what causes the tank to be pressurized?
We are suspecting that my walbro is faulty... I dont want to have to buy another one (since they offer NO warranty on it) but this may be the culprit...

jgrewe · 10-01-2008, 06:44 PM

Take the top off of one of your stock FPR's and put an adjustable top that is made for a Honda on it. B&M makes them, they are about $50 from Summit racing.

classicauto · 10-02-2008, 07:50 AM

Quote:

Originally Posted by stylEmon

So what causes the tank to be pressurized?

Poor venting. Are you running a charcoal canister?

stylEmon · 10-02-2008, 08:48 AM

no...

TehMonkay · 10-02-2008, 02:51 PM

So, do you just have a cap on the line on the firewall going to it?

stylEmon · 10-02-2008, 03:45 PM

pretty sure its all capped... not positive. I'll have to check it out.
So high fuel pressure is a symptom of this? What other ill effects from running no canister? or capped off lines?

classicauto · 10-03-2008, 07:11 AM

Capping the vent for the tank will do some things......I'm not sure if high fuel pressure would be one of them, although its ENTIRELY possible.

All that vent's doing is essentially what the "vent" hole on a gas can does. It allows air to replace the space occupied by fuel once you start suckign fuel out. Does the reverse when you start pouring fuel in.

Its vented through the charcoal canister to keep fumes down, other wise you'd probably smell fuel coming out of the hole.

I've seen gas tanks collapse inwards from a plugged vent + heavy duty fuel pump.

stylEmon · 10-03-2008, 09:02 AM

yikes. makes sense tho.
Will look into that.

stylEmon · 10-12-2008, 10:31 AM

it is not capped off, so thats not a problem.
It is the fuel pump. I've been having issues with this pump for a while. Sometimes the pump would be really loud, other times not so loud... and it didn't matter what the fuel level was. I should've returned it months ago but now I am stuck buying another walbro!!

10-12-2008, 11:50 AM

loud pump = bad pump.. sorry to hear looks like a new pump is in order.

09-30-2008, 03:39 PM	#1
stylEmon Rotary Fanatic Join Date: Feb 2008 Posts: 125 Rep Power: 18	Stock FPR Problems: Who else... Has anyone had problems with the stock FPR? I am curious because I am having issues with Fuel Pressure. I have an new filter, new lines from filter to rails, stock rails, 1600cc Bocsh secondaries, no pulsation dampener and stock fpr. (Walbro Hi Flow pump) I noticed pressure issues, and took off the stock fpr. Replaced it with another stock one and am having the same issue. It's possible that both fpr's are faulty. I would even say it's probable. Anyone have any insight or similar problems? Obviously I want to upgrade to an Aeromotive with braided lines and AN fittings, but I don't want to spend the $600 on that right now.. Thanks __________________ See the Rebuild Process Here Curious About Deadband Timing? The BLACK BEAST is For Sale

09-30-2008, 07:15 PM	#3
stylEmon Rotary Fanatic Join Date: Feb 2008 Posts: 125 Rep Power: 18	not sure why that would be a problem. I have a stand alone. The main problem is at idle. The fuel pressure is 20 psi higher than it should be. Under load it raises a little more. __________________ See the Rebuild Process Here Curious About Deadband Timing? The BLACK BEAST is For Sale

10-01-2008, 03:26 PM	#5
TehMonkay Rotary Fanatic Join Date: Apr 2008 Location: Louisville, KY Posts: 302 Rep Power: 18	It's either not bypassing enough fuel or there's a clog in the line or your fuel tank is very pressurized. __________________ My car blows up everytime I start it, it's rotary

10-01-2008, 04:42 PM	#6
stylEmon Rotary Fanatic Join Date: Feb 2008 Posts: 125 Rep Power: 18	I think its always been a problem since I had this car running after the engine build. It was masked by other problems, or unfinished tuning... make sense? So what causes the tank to be pressurized? We are suspecting that my walbro is faulty... I dont want to have to buy another one (since they offer NO warranty on it) but this may be the culprit... __________________ See the Rebuild Process Here Curious About Deadband Timing? The BLACK BEAST is For Sale

10-01-2008, 06:44 PM	#7
jgrewe Rotary Fan in Training Join Date: Feb 2008 Location: On the Beach Posts: 59 Rep Power: 18	Take the top off of one of your stock FPR's and put an adjustable top that is made for a Honda on it. B&M makes them, they are about $50 from Summit racing. __________________ New rat from the sinking ship.

10-01-2008, 07:35 AM	#4
classicauto crash auto?fix auto Join Date: Feb 2008 Posts: 816 Rep Power: 18	Hmmm. When did you first noticce the issue? Anything else changed/going on in that time period?

10-02-2008, 08:48 AM	#9
stylEmon Rotary Fanatic Join Date: Feb 2008 Posts: 125 Rep Power: 18	no... __________________ See the Rebuild Process Here Curious About Deadband Timing? The BLACK BEAST is For Sale

10-02-2008, 02:51 PM	#10
TehMonkay Rotary Fanatic Join Date: Apr 2008 Location: Louisville, KY Posts: 302 Rep Power: 18	So, do you just have a cap on the line on the firewall going to it? __________________ My car blows up everytime I start it, it's rotary

10-02-2008, 03:45 PM	#11
stylEmon Rotary Fanatic Join Date: Feb 2008 Posts: 125 Rep Power: 18	pretty sure its all capped... not positive. I'll have to check it out. So high fuel pressure is a symptom of this? What other ill effects from running no canister? or capped off lines? __________________ See the Rebuild Process Here Curious About Deadband Timing? The BLACK BEAST is For Sale

10-03-2008, 07:11 AM	#12
classicauto crash auto?fix auto Join Date: Feb 2008 Posts: 816 Rep Power: 18	Capping the vent for the tank will do some things......I'm not sure if high fuel pressure would be one of them, although its ENTIRELY possible. All that vent's doing is essentially what the "vent" hole on a gas can does. It allows air to replace the space occupied by fuel once you start suckign fuel out. Does the reverse when you start pouring fuel in. Its vented through the charcoal canister to keep fumes down, other wise you'd probably smell fuel coming out of the hole. I've seen gas tanks collapse inwards from a plugged vent + heavy duty fuel pump.

10-03-2008, 09:02 AM	#13
stylEmon Rotary Fanatic Join Date: Feb 2008 Posts: 125 Rep Power: 18	yikes. makes sense tho. Will look into that. __________________ See the Rebuild Process Here Curious About Deadband Timing? The BLACK BEAST is For Sale

10-12-2008, 10:31 AM	#14
stylEmon Rotary Fanatic Join Date: Feb 2008 Posts: 125 Rep Power: 18	it is not capped off, so thats not a problem. It is the fuel pump. I've been having issues with this pump for a while. Sometimes the pump would be really loud, other times not so loud... and it didn't matter what the fuel level was. I should've returned it months ago but now I am stuck buying another walbro!! __________________ See the Rebuild Process Here Curious About Deadband Timing? The BLACK BEAST is For Sale

10-12-2008, 11:50 AM	#15
SpooledupRacing Guest Posts: n/a	loud pump = bad pump.. sorry to hear looks like a new pump is in order.