Hard warm start 93 f150

My 93 ford f-150 dual tanks, 351 has started to crank longer to start when warm.It usally starts on about 3 cranks and now is up to

6 or 7 cranks. The battery is new. I put a fuel pressure tester on it and it has 34 pounds both tanks when running. and open the throttle it goes up 6 or 8. But when i shut the truck off, the pressure drops off almost imediatley. I pulled the hose off the fuel pressure regulator and there is no fuel leaking in the hose and i put a vacum pump on it and it holds vacum so i dont thing the diaphram is leaking. Could it be injectors leaking down? Other than the hard starting it seems to run fine. I havent pulled any codes yet. I have faithfully run and injector cleaner in the truck. Thanks in advance.

If your injectors are leaking it could be 'flooding' your engine and it takes a few extra cranks to clear the extra gas. Also, how long does it take to build up fuel pressure after turning on your ignition? There may be a little delay in getting enough pressure for the injectors to operate. And, if your injectors are leaking, this will be dumping even more gas into the engine, while the pressure is building up.

This is not so much of a problem when the engine is cold and you need a richer mixture. But, leaks will also cause you to use more gas than you should be.

Check your spark plugs. Are they wet? Do they smell strongly of gas? Are they black? To check, warm up your engine, shut it down, restart it and shut it back down. Pull plugs one at a time and make note of plug condition and the cylinder that it came out of. What is the plugs general condition and gap? This may give you an idea of what is happening and in which cylinder(s) the problem lies.

Also, check the timing and spark strength.

Partial list of plug conditions. Insulator color Condition Tan Normal White Lean and/or Hot (Plugged injectors?) Black Rich and/or Cold (Leaking injectors?) Wet (Gas) Rich (Leaking injectors?) Wet (Oil) Leaking valve seals and/or rings

BigDave