My truck is hard to crank in the morning. on 1990 Ford E-150

When I go to crank my truck in the morning I turn the switch on and I hear the fuel pump come on.Sometimes it keeps running like its not building up pressure and the truck is very hard to get cranked.When I turn the switch on and hear the pump run and cut off the truck cranks fine.I noticed the other day when I turned the switch to accessories the fuel pump come on.Any ideas would help.Thanks

by in Benson, NC on August 25, 2012
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2 answers 1 comment
ANSWER by , August 25, 2012
Try this. Before trying to start, cycle (turn the ignition switch) from off to run (that's when all the dash lights come on) 5 times, leaving it in the run position for 5-8 secs each cycle, then try to start the engine. If it pops right off, your fuel pump most likely needs replaced (it's in the tank). If that doesn't create a change, there is an electrical pulse issue between the crank sensor & computer (fairly unlikely), or a failing crank sensor (more likely). There is an outside chance you have injectors stuck open, causing pressure bleed off, as they drain the primed fuel (when you rotate to run & hear the pump) into the cylinders. It can be just one causing the problem, and if you suspect that, & have a multimeter, check the resistance across each injector (should be 10-16 ohms, approx). Usually if you have an injector issue, you will alo have an issue with how the engine runs, esp at idle.
COMMENT by , August 25, 2012
Or have scan test. Unless auto savvy. Profile don't say.
ANSWER by , August 25, 2012
Have fuel press. test Coolant temp. sensor test,scan test.