Leaking Injector/s??
Thread Starter
Burning Brakes
Joined: Aug 2004
Posts: 771
Likes: 0
From: Washington District of Columbia
Leaking Injector/s??
If hard starting is a result of a leaking injector or injectors, will the
gas be noticeable on the manifold/engine. Or where would it leak to if
it cannot be seen? Thanks.
gas be noticeable on the manifold/engine. Or where would it leak to if
it cannot be seen? Thanks.
Safety Car
Joined: Jan 2008
Posts: 3,939
Likes: 1
From: Vero Beach Florida
Depends on if the O-rings are leaking I would think you would see gas on the manifold. If the injectors are leaking into the engine after the car is off you might not see any gas, but I would think you would smell it @ start up. Check to see how fast you’re losing fuel pressure with the car off. Then ohm check the injectors.
Race Director
Joined: Mar 2006
Posts: 11,628
Likes: 1
From: Sherwood, Arkansas
My first symptom on my '92 was hard, hot starts. I got to looking around and I had fuel on the manifold at two injectors on the driver side. A steady, fine stream after shutoff on a hot engine and occasionally I would smell fuel after a lengthy drive. Fire waiting to happen.
Le Mans Master
Joined: Oct 2004
Posts: 6,314
Likes: 508
From: South-central Missouri
A couple things to try...
A hard start is one symptom of an injector (one or more) leaking into the engine. A leaking O-ring will result in fuel spilling out, leaving a stain on the intake (a serious fire hazard too!)
With a fuel pressure gauge connected to the Shrader valve on the fuel rail, turn the switch on to pressurize the fuel rail. Then turn the switch off and monitor the fuel pressure. With a possible instant drop of a couple pounds (maybe), it should hold - not loosing more than a pound or three over 5 minutes.
If the pressure bleeds off, you might be experiencing fuel leaking back past the stop valve in the fuel pump. To eliminate that, you would need to pinch off the rubber hose once pressure is established and before you turn the key off. Then if pressure continues to bleed off, you might have an injector problem. (Just be glad it isn't an LT5 - with 16 injectors - and the access to the fuel rails is under the plenum!
)
P.
With a fuel pressure gauge connected to the Shrader valve on the fuel rail, turn the switch on to pressurize the fuel rail. Then turn the switch off and monitor the fuel pressure. With a possible instant drop of a couple pounds (maybe), it should hold - not loosing more than a pound or three over 5 minutes.
If the pressure bleeds off, you might be experiencing fuel leaking back past the stop valve in the fuel pump. To eliminate that, you would need to pinch off the rubber hose once pressure is established and before you turn the key off. Then if pressure continues to bleed off, you might have an injector problem. (Just be glad it isn't an LT5 - with 16 injectors - and the access to the fuel rails is under the plenum!
)P.
