FI and fuel
#1
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Don't know if this is the right section, but I've got a fuel related question. If I am "boost referenced" when the car is sitting at a nice idle and I rev the throttle, the boost gage goes from vac to boost... that quick. In boost, since the fuel sys is "Boost referenced" she adds fuel. The problem is when the car idles down she has alot of fuel in her "rich" that she dosen't need... this causes stumbling, fouling and or kills the car until the excess fuel is burned off. How do you get a FI car to over come this?
Any help appreciated
Any help appreciated
#4
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I had the fuel pressure regulator go bad on mine, so when it was at idle under vacuum it was sucking raw gas right into the intake manifold and drowning out my back four plugs. Mine behaved kind of the same way.
#6
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I just bought a new one when I knew for sure it was bad, but they might make a rebuild kit for some of them. What I did to test mine was take the vacuum hose off the fuel pressure regulator and hook a vacuum gauge with a clear line to it. Then I pumped it up to 12-14 psi like what would normally be present at idle and gas started coming right into the clear line.
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explain this..... so with the car NOT running, remove the vac line and put 12-15 lbs vac on it and what should happen or should not happen and where am I looking for this at.
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#8
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What I did was get the vacuum gauge and clear line hooked up to the fuel pressure regulator with the car turned off. Then I started it up so you had the normal gas flow from the fuel pump. Then while it was idling I pumped up the vacuum gauge to simulate the normal idle vacuum that would typically lower your fuel pressure at idle. Since mine was bad, I could actually see the gas come right from the fuel pressure vacuum fitting into my clear line once I had the vacuum pumped up on it.