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Re: 89 F250 460 Won't start on first try
First thing I'd do is a fuel pressure static test. Most FI systems need to maintain some minimal pressure when the system is off, otherwise symptoms like you describe can occur. I don't know the spec for that system offhand, but it should be available with all the other pertinent data. What you need to do is attatch a fuel pressure gauge and allow the vehicle to sit for a while - or overnight. Before you attempt to start it check the pressure on the gauge - if it is below the spec then you need to determine why the system is leaking down. There are 3 places you can lose pressure - the regulator, the check valve (usually in the pump) or through the injectors. To determine which one you have to eliminate them - first close off the return line between the regulator and the tank. If the pressure stays up then the regulator is defective. If not, close off the line between the fuel rail inlet and the tank. If this makes the pressure stay up then the pump is probably the culprit. If neither of these prevents the pressure loss then one or more of the injectors is leaking down. At that point I would remove them and have a competent shop peform a flow/leakage test on all 8 and repair/replace them as needed.
It is possible something else is the source of your problem, but I'd start with an overnight pressure test....
Gregg
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