Fuel pressure spike on execration?
#1
Fuel pressure spike on acceleration. (Pressures not holding again)
I'm having trouble yet again… this truck is on it's 6th(?) fuel pump, and third spider.
Last october I was having troubles and couldn't pin it down, got pissed and changed everything, pump, spider and FPR. Troubles went away. Now 8 months later it's starting to act up. I put the pressure gauge on it; key on to 60+, running at 50+. But when I hit the gas, the pressure jumps up to 60. Is that normal for an electric fuel pump or am I just not remembering correctly? I don't remember it doing that in the past, but that might be just it, that I'm just not remembering it.
Last october I was having troubles and couldn't pin it down, got pissed and changed everything, pump, spider and FPR. Troubles went away. Now 8 months later it's starting to act up. I put the pressure gauge on it; key on to 60+, running at 50+. But when I hit the gas, the pressure jumps up to 60. Is that normal for an electric fuel pump or am I just not remembering correctly? I don't remember it doing that in the past, but that might be just it, that I'm just not remembering it.
Last edited by cas; 07-30-2013 at 09:01 AM. Reason: Because I should never try and type anything on my phone.
#2
as far as I know, there is no spec for a running engine. To many variables. key on is 60, what has it leaked down to after 10 min?
#3
Oh it's dropping real quick. Down to 30 in about 6 minutes. That's when I unhooked it and walked away pissed off. I'm getting so tired of this BS.
#4
What brands of spider and pump are you getting?
#5
pressure spike on acceleration is normal, the regulator has a "vacuum control" that under vacuum reduces pressure, but when accelerating or when off "little to no vacuum" it rises. Its not the pump
#6
The spiders were STANDARD and ACDELCO, though I don't remember which was first and which is in there now.
I didn't change all the pumps, I'm the 3rd owner. First owner did one or two, second owner, an auto mechanic by trade did three of different brands and I believe one for another vehicle all together in an attempt to get something that worked/lasted better. The one I installed in October was a Bosch, because it was the better of the two I could get locally. It was that or push the truck, I couldn't wait to order one.
I didn't change all the pumps, I'm the 3rd owner. First owner did one or two, second owner, an auto mechanic by trade did three of different brands and I believe one for another vehicle all together in an attempt to get something that worked/lasted better. The one I installed in October was a Bosch, because it was the better of the two I could get locally. It was that or push the truck, I couldn't wait to order one.
#7
To determine if it's that Botched fuel pump, test pressure at either the pump itself or the fuel filter, thereby removing the spider/regulator from the equation.
#8
What will that tell me? If it's leaking at either the spider or the FPR, it's still going to, just farther away. Wouldn't that show me just what I'm seeing now?
#9
down to 30 in 6 min isn't really quick and will probably cause little no no problems, the regulator will show signs of washing. The spider is the whole assembly
#10
It's funny, all the years I've owned this truck, I've had the front wheels off a grand total of once. Yet I've had the top of the engine off 6-7 times. lol
Pulled the plenum, no signs of washing. All the poppets are locked in place, nut kit looks good, no leaks. Phooey.
Pulled the plenum, no signs of washing. All the poppets are locked in place, nut kit looks good, no leaks. Phooey.
Last edited by cas; 08-03-2013 at 12:13 PM.