Fuel Pressure drops to 25 psi
02-09-2006 | 02:28 PM
#22
Have you double checked all of the electrical connections?
With that small blip down to 25psi...
Maybe a wire shorting out against the frame or something under hard acceleration?
Just a thought.
With that small blip down to 25psi...
Maybe a wire shorting out against the frame or something under hard acceleration?
Just a thought.
02-09-2006 | 02:39 PM
#23
You might want to tap the fuel pump hot and ground
wires, as close as possible to the pump itself (preferably
past the last connector outside, toward the tank) and
check the delivered voltage under load. Might be as
simple a problem as a crusty ground screw somewhere,
or a relay that's gotten more contact resistance, a
corroded connector etc. The wiring is known marginal
to begin with.
Also might want to cobble up a pressure sender back
where the T sends gas back to the regulator and see
if the problem is forward line restriction of some sort.
wires, as close as possible to the pump itself (preferably
past the last connector outside, toward the tank) and
check the delivered voltage under load. Might be as
simple a problem as a crusty ground screw somewhere,
or a relay that's gotten more contact resistance, a
corroded connector etc. The wiring is known marginal
to begin with.
Also might want to cobble up a pressure sender back
where the T sends gas back to the regulator and see
if the problem is forward line restriction of some sort.
02-09-2006 | 03:32 PM
#24
Thread Starter
Joined: Nov 2001
Posts: 3,066
Likes: 0
From: Sunny San Diego
Good idea on the wiring. I am running the Racetronix wiring harness and have it connected to the alternator.
I'll double-check the the ground.
I'll double-check the the ground.
Originally Posted by jimmyblue
You might want to tap the fuel pump hot and ground
wires, as close as possible to the pump itself (preferably
past the last connector outside, toward the tank) and
check the delivered voltage under load. Might be as
simple a problem as a crusty ground screw somewhere,
or a relay that's gotten more contact resistance, a
corroded connector etc. The wiring is known marginal
to begin with.
Also might want to cobble up a pressure sender back
where the T sends gas back to the regulator and see
if the problem is forward line restriction of some sort.
wires, as close as possible to the pump itself (preferably
past the last connector outside, toward the tank) and
check the delivered voltage under load. Might be as
simple a problem as a crusty ground screw somewhere,
or a relay that's gotten more contact resistance, a
corroded connector etc. The wiring is known marginal
to begin with.
Also might want to cobble up a pressure sender back
where the T sends gas back to the regulator and see
if the problem is forward line restriction of some sort.
02-09-2006 | 11:27 PM
#26
Thread Starter
Joined: Nov 2001
Posts: 3,066
Likes: 0
From: Sunny San Diego
Ok, so I decide to go back to my old tune before all this started.
And wouldn't you know it? My AFR is back the way it was. Anywhere from 10.7 to 11.7.
Didn't see the FP drop below 40.
I don't get it.
And wouldn't you know it? My AFR is back the way it was. Anywhere from 10.7 to 11.7.
Didn't see the FP drop below 40.
I don't get it.
02-12-2006 | 07:23 AM
#29
Did you check you inj dc with the other tune that the pressure dropped on?? Your inj may be spraying so much that the pumps cant keep up. I think that's what I am running into. When my inj dc was over 100% with 50 lbs. inj my pressure would drop to 20-25 psi with the racetronix. I added a second intank 255lph and now my pressure only drops to about 35-40. I was also able to lower the inj dc because of the methanol. Not a lot of help but some none the less.
