Fuel Economy, Hypermiling, EcoModding News and Forum - EcoModder.com - View Single Post

user removed · 02-20-2015, 08:33 PM

Check to see if the fuel rail will hold pressure. Could be the pressure regulator is leaking into the intake manifold through the vacuum port (bad diaphragm). The 02 sensor is trying to lean the mixture out but the fuel leaking past the regulator diaphragm is overwhelming the feed back system with unmetered fuel.

If the fouled plugs are closest to the vacuum port to the pressure regulator then that is more evidence to support that conclusion.

Disconnect the vacuum hose to the regulator and look for leaking fuel coming from the regulator diaphragm. Turn the ignition on to run the fuel pump, but you might not want to start it.

If you find that my scenario is correct then you might consider changing the oil and cleaning the plugs. You could reuse the filter.

regards
mech

02-20-2015, 08:33 PM	#5 (permalink)
user removed Master EcoModder Join Date: Sep 2009 Posts: 5,927 Thanks: 877 Thanked 2,024 Times in 1,304 Posts	Check to see if the fuel rail will hold pressure. Could be the pressure regulator is leaking into the intake manifold through the vacuum port (bad diaphragm). The 02 sensor is trying to lean the mixture out but the fuel leaking past the regulator diaphragm is overwhelming the feed back system with unmetered fuel. If the fouled plugs are closest to the vacuum port to the pressure regulator then that is more evidence to support that conclusion. Disconnect the vacuum hose to the regulator and look for leaking fuel coming from the regulator diaphragm. Turn the ignition on to run the fuel pump, but you might not want to start it. If you find that my scenario is correct then you might consider changing the oil and cleaning the plugs. You could reuse the filter. regards mech Last edited by user removed; 02-20-2015 at 08:41 PM..