Hi all,

Im Andy from across the pond and i have the pleasure of owning a l03 RS camaro 5.0 Tbi

I find its slow to take off and feels very slow from standing start with no power.

After doing some searches I thought id check fuel pressure.

With the fuel line into the tbi disconnected, and connected to a gauge the pressure on the turn of the key i get 15psi. If i install the gauge inline and run the engine it drops to 5psi on idle.

So i think fuel pump is naff, but if i clamp the return fuel line the pressure jumps to 20psi. So then i figure the regulator is naff. a online order to Rock auto later and a new regulator kit turns up (gen ac delco) I fit the new reg and no change. Fuel pressure when running is 5psi, if i rev the engine the pressure drops further slightly.

Any ideas............

 

sure your gauge is accurate?

 

Thanks for the quick reply.

Well that is one question im not sure about. Only thing i can do is buy a new one and test again.

I did order a new delco pump kit too, but as its making 20psi when i clamp the return im not sure its at fault.

I suppose i should check the pressure again with a known gauge.

Just to clarify, when the engine is idling it should have 9 - 13psi at the throttle body?

 

correct and same under load. I would run a line to windshield with duct tape from fitting at TB and have passanger witness FP under a WOT load.

 

word up!

im guessing the little hose inside the tank might have a leak, or a dieing pump. been there, done that lol. id have pressure at 12psi until it warmed up ( about 5 minutes) it dropped to 5, got to the point my car stalled and it was at 1 psi. mine was the pump, but after tons of research on this forum, alllloooot of people had that little hose go bad on them. hope this helps.

 

I was told reformulated blend gas not necessarily ethanol(E10) causes havoc on fuel lines(plastic/rubber whatever thay are made of). My 2005 snowmobile being 8 seasons of use now gas tank pickup line just decided to falll off. I fished out of tank and it appeared to be hard as a rock and looked melted. Anyway there are some new flex fuel lines out now that are available. If anyone replaces one it may pay to get that new coupound...

 

Your pump cannot supply appropriate VOLUME even though it can provide pressure when there's no fuel flow.

Pump, pump sock, and/or fuel filter is toast. If the fuel filter is plugged, the pump has been working extra-hard to force fuel through the plugged filter, and is probably not long for this world. If the pump sock is plugged, the pump has been starved on the inlet side, and is probably not long for this world.

I don't see any reason to suspect the gauge is inaccurate, as it seems to provide reasonable reading when there's no fuel flow; and it would be common enough to have ~5 psi with a plugged filter or failing fuel pump--and the symptoms match the diagnosis.