Went to the dyno today...fuel issue FML. need assistance
04-15-2011, 04:20 PM
#21
4th Gear Member
Thread Starter
Join Date: Apr 2008
Location: mi
Posts: 1,087
ALright. About 38-40 psi wot up to about 4grand didnt wanna push it ne farther. Shouldnt it be way higher with dual pumps? And now it only wants to be at 15-20 psi at idle. Only 5 psi when primed.
04-15-2011, 04:33 PM
#22
TECH SAVANT
Join Date: Dec 2006
Location: Saint Augustine, FL
Posts: 10,938
If so, then adding the dual pumps has done nothing but further screw things up. You need to find a builder and tuner that know what they are doing...
04-16-2011, 12:37 PM
#25
TECH SAVANT
Join Date: Dec 2006
Location: Saint Augustine, FL
Posts: 10,938
Here's a great description of how the returnless system works, from Kenne Bell.
How much boost do you run? I understand rupturing the FRP sensor diaphragm it fairly common on higher boost Cobras.
With a 0psi equivalent signal coming from the FRP sensor the PCM would hold the fuel pressure at 39-40psi...
How much boost do you run? I understand rupturing the FRP sensor diaphragm it fairly common on higher boost Cobras.
With a 0psi equivalent signal coming from the FRP sensor the PCM would hold the fuel pressure at 39-40psi...
04-16-2011, 01:15 PM
#26
4th Gear Member
Thread Starter
Join Date: Apr 2008
Location: mi
Posts: 1,087
everything worked great with one fpdm and a single fuel pump with the BAP with the vortech with 14psi.
tore everything apart and went turbo.. switched to dual fpdm's cobra hat with dual pumps and the BAP havent had it over 5psi becuase i'm not getting the fuel at the rail.
so really no more than 5 psi cuz i can;t get on it.
do u know where the frp sensor is?
so your not thinking its the pumps?
tore everything apart and went turbo.. switched to dual fpdm's cobra hat with dual pumps and the BAP havent had it over 5psi becuase i'm not getting the fuel at the rail.
so really no more than 5 psi cuz i can;t get on it.
do u know where the frp sensor is?
so your not thinking its the pumps?
04-16-2011, 03:49 PM
#27
TECH SAVANT
Join Date: Dec 2006
Location: Saint Augustine, FL
Posts: 10,938
The only thing known right now is that it appears to be a fuel system problem At 5psi boost the fuel pressure should have been 45psi or so--if the FRP sensor was doing it's job (it could have been that one or more of those 14psi runs damaged it, who knows?).
The Fuel Rail Pressure sensor is in the middle of the driver's side fuel rail, on top, and has a vacuum line, and electrical connector. Depressurize the fuel system before removing it.
It looks like this:
The Fuel Rail Pressure sensor is in the middle of the driver's side fuel rail, on top, and has a vacuum line, and electrical connector. Depressurize the fuel system before removing it.
It looks like this:
Last edited by cliffyk; 04-16-2011 at 05:02 PM.
04-16-2011, 05:03 PM
#29
TECH SAVANT
Join Date: Dec 2006
Location: Saint Augustine, FL
Posts: 10,938
Hangwire, thanks for the proof-reading--for some reason my brain was thinking "driver's" but the fingers typed passenger--this gettin' old crap gets in the way sometimes...
04-16-2011, 05:07 PM
#30
4th Gear Member
Join Date: Jul 2008
Location: NC
Posts: 1,956
Not a problem man. Youve forgotten much much more than i'll know about these cars and plenty more. Care to do a brain swap? I'll give you a young, fresh, testosterone driven horny brain for a wiser, learned, ocassionally forgetful brain no cash added! I will warn you that you may not be a fan of the music this brain likes.
Thread
Thread Starter
Forum
Replies
Last Post
