I have a 92 ford F150 302. Everytime I try to start the truck I MUST push the gas pedal to the floor in order to get the thing to start. it is fuel injected. This has always been the case since this engine has been replaced. I'm not sure where the problem lies. I do hear the pump turn on then off. It will not start by just turning the key at anytime. I'm not a firm believer in it being the filter since it will idle. It could be a pressure regulator but I'm not fully convinced nor do I want to just start replacing items until it's fixed. It could possibly be some other issue that I'm not familiar with.
It turned out that the temp sensor was defective and open (high resistance around 12 meg!). The resistance of the new thermistor for the truck was around 24k ohms at around 80 degrees.
When you push the accelerator to the floor you turn off the injectors. Since the old temp sensor was open, it was simulating a cold start of around -40 degrees thereby enriching the mix with a lot of fuel. Since the injectors dumped so much fuel, I needed to depress the accelerator to the floor to clear out the fuel in order to start the truck.
Thanks for the complement. Actually, I asked a mechanic friend about the problem and he said that the f150's have this common problem. I don't know if I agree with that since it's a simple thermistor and they are very robust. I was at a crossroads when he suggested the temp sensor. It made sense on why it could be that and guess what, he was right! I actually had gone through changing the timing chain, spark plugs, rotor, distributor cap, and ignition coil before getting to the temp sensor. These problems helped nail it down.