351w starting problem
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351w starting problem
my 78 f250 has recently started to start harder. it has a 351w and once it starts it runs perfect-NO power loss,missing or rough idle. it just seems that i have to hold the key longer and longer every time in order for it to start. once it has started and run it will start right back up when it's hot. i was thinking fuel filter because it's been a while so i'll try that first
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Joined: Jan 2001
Posts: 57,025
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From: Virginia
You may have a wire off or missing on the starter relay, if it has two small posts on it.
To help the engine start quicker, the factory puts a full 12 volts to the coil + during cranking. After the engine has started, the coil gets it's voltage through a resistor which puts less than 12 volts to the coil.
Put a meter on the coil + and the engine block, and read the voltage during cranking and then after it starts. You should have a fairly high reading during cranking, and then you should have around 9 volts when it's running.
I am assuming you have done a tune up lately and your sparkplugs are in good shape.
To help the engine start quicker, the factory puts a full 12 volts to the coil + during cranking. After the engine has started, the coil gets it's voltage through a resistor which puts less than 12 volts to the coil.
Put a meter on the coil + and the engine block, and read the voltage during cranking and then after it starts. You should have a fairly high reading during cranking, and then you should have around 9 volts when it's running.
I am assuming you have done a tune up lately and your sparkplugs are in good shape.
