My engine is hard to start after driving for a while. The engine is not overheating. It will start with the key only, and easily when it's cool. I have to pump the pedal and continue cranking for at least 10 seconds in order to start the engine. I have replaced the Rochester valve, replaced the chains and tensioners, cleaned the Throttle Body, new plugs, cleaned the MAF, and changed the gasoline filter. When it starts, it runs with no problems whatsoever. I have no codes from the ecm. I was getting a lot of oil in the air intake and am replacing the valve cover on the passenger side due to a bad oil separator. I reopened the small clog in the part load breather line which was restricted. I have ordered a new boot gasket for the air tube to the TB. It seems a little loose and I think air might be getting in there. Other than that, I don't know what else to try. Any help???

 

Pumping the pedal is a feel good reminder from the past because fuel injected engines don't have accelerator pumps to sweeten the fuel mixture like carberated engines from yesteryear had. I think the crux of your hot start problem is likely electrical which is an area I leave to the younger enthusiasts that make up this forum. Theoretically the amount of cranking time with your foot off the accelerator during a warm engine start should be the same as when you 'pump' it. Someone in here will give you the probable cause and likely cure.

 

When warm, if you shut the car off and immediately restart it, is there any hesitation?

If it only gives you a long crank after sitting for a time, the it sounds like a fuel problem.

Check the fuel pressure with an external gauge using the schrader valve on the fuel rail. When you turn the key on it should come up to 55psi (give or take) immediately. If it doesn't, cycle the key a time or two more but don't crank it. This will cause the fuel pump to run a few seconds each time the key is switched on. Once you see pressure, it should start.

As said before, the pumping does nothing in a modern car.

If the above works, then it could be a faulty check valve or fuel pressure regulator.

 

After checking there was enough pressure in my fuel line, I changed the coolant temperature sensor, even though it was registering okay. The FSM suggested this as well as changing the rochester valve which I did first but didn't help. It was the coolant temperature sensor. Cheap and easy fix. Thanks for all the suggestions and help.

 

Thanks for posting the resolution of your hard to start issue.

I've added 'RESOLVED' to your thread title to help others looking for help with this issue in future.

Graham