Installed walbro 450, now fuel pressure reads 100 psi!!
#1
Safety Car
Thread Starter
Installed walbro 450, now fuel pressure reads 100 psi!!
I am checking my fuel pressure at the rail, and the gauge reads 100 psi!!
If I were to kink the line for the jet pump going to the other tank, would it be possible for the fuel pressure to shoot up to 100?
When I first started the car, it made about 65psi. I ran it for about 10 min checking for leaks, etc. After that I took it for a drive. About 3-4 miles in, the pressure started to creep up to 100. Now, after running for only a few moments it creeps up to 100!!
Any insight would be greatly appreciated
Tony
If I were to kink the line for the jet pump going to the other tank, would it be possible for the fuel pressure to shoot up to 100?
When I first started the car, it made about 65psi. I ran it for about 10 min checking for leaks, etc. After that I took it for a drive. About 3-4 miles in, the pressure started to creep up to 100. Now, after running for only a few moments it creeps up to 100!!
Any insight would be greatly appreciated
Tony
#4
Team Owner
Over running the stock reg?
#8
Safety Car
Thread Starter
Can you please show me an example or two where others had a problem? I'm not saying that creating a return style system wont work, but I am unsure if its the problem.
It was fine (65 psi) for about 15 min and then it shot up. I suspect that the jet pump system may be suspect. It is possible that I kinked that line or the return from the other side, and I wonder if it would make fuel pressure skyrocket.
It was fine (65 psi) for about 15 min and then it shot up. I suspect that the jet pump system may be suspect. It is possible that I kinked that line or the return from the other side, and I wonder if it would make fuel pressure skyrocket.
#9
Burning Brakes
Yeah you might want to check it out because mine never shot that high and I'm using a stock regulator. But I've seen it happen before with mitsu evos with changing the stock pump and over running the factory regulator. But they fix it with an aftermarket regulator.
-Curtis
-Curtis
#10
Most likely you have the bypass or one of the jet pump lines kinked. I know that in my car with the 450 and racetronix rewire I still couldn't get to 43lbs base pressure with a small hole in one of the jet pump lines so those lines will affect pump output a lot.
#11
Supremacy 1 car at a time
Tony that's may help you I had the same issue with my car, if your gauge is AEM then gauge is not reading at all.
Last edited by ProEFI; 01-06-2015 at 08:47 PM.
#13
Supremacy 1 car at a time
what am trying to say I had the same issue and I fogger out that the sensor wasn't reading on my AEM gauge, I thud you running AEM so that suggest to check your gauge.
#14
Safety Car
Thread Starter
I tried two different gauges, and had the same results. I pulled the tank again, and checked the crossover lines for any kind of kinks and found none.
I was trying for an economy fuel system upgrade, but it seems that simply wont be the case. As stated above, it seems clear the stock regulator cant handle the new pump.
I just don't understand why the pressure doesn't jump right up to 100. When I start it, it starts at 65, and over time (5 Min ) it creeps up to 100. It just doesn't make sense.
I was trying for an economy fuel system upgrade, but it seems that simply wont be the case. As stated above, it seems clear the stock regulator cant handle the new pump.
I just don't understand why the pressure doesn't jump right up to 100. When I start it, it starts at 65, and over time (5 Min ) it creeps up to 100. It just doesn't make sense.
#15
Le Mans Master
You may want to bench test the assembly and/or take the regualator out of the bucket and inspect or replace it. I have two Walbro 255's Y'ed together in the stock bucket running all the time and I get 65# at idle and cruise and it drops to ~55# under WOT. The fact that its not shooting to 100 right away would indicate that it's not simply that the pump is putting out too much.
#16
Team Owner
Member Since: Jan 2007
Location: cookeville tennessee
Posts: 28,846
Received 1,762 Likes
on
1,529 Posts
#18
Instructor
#19
Burning Brakes
I've been looking into 450 install stuff for a while now. Still not comfortable with pulling the trigger. Did u ever get this sorted out?
Im trying to figure out why some people claim the stock regulator won't keep up yet others disagree. Is it because most people do affect their fuel pressure and just don't know it? I suppose it could get baked into the tune, but I'm not cool with that.
Im trying to figure out why some people claim the stock regulator won't keep up yet others disagree. Is it because most people do affect their fuel pressure and just don't know it? I suppose it could get baked into the tune, but I'm not cool with that.