My truck has been giving me trouble starting lately. It will crank much longer than normal, but then start and run perfectly after that. It's usually the first start of the day, it may or may not start harder later in the day. The starter spins at the normal speed, so the battery and starter should be good. I replaced the fuel filter and spark plugs after this started happening, but that didn't help anything. Hooked it up to the scanner, didn't throw any codes and no CEL on. I'm really hoping it's not the fuel pump, but I don't know what the symptoms of that are. Someone told me it might be the fuel pressure regulator, but the only test I could find online is to pull the vacuum hose and look for gas coming out, but didn't have that happen.

So I guess my question is, could it still be the fuel pressure regulator? Anything else I should be looking into?

 

Forgot to mention, my truck has about 125,000 miles on it.

 

Do you know the idle rpm's?

 

My truck did it also. It was the check valve in the fuel pump assembly that was bad. I added a check valve in the fuel line between the fuel filter and gas tank and that solved the problem.

 

I do not, no. It hasn't dropped any lower than normal, and once it starts it idles smoothly.

EDIT: Last time I drove the truck I paid attention to the idle speed; with the engine warm and accessories off, it idled right around 600rpm.

 

How did you figure out that was the problem? Any test you can do without specialty tools?

 

Well, I got it fixed. All the symptoms were pointing to the check valve in the pump like oldchevy said, but I first replaced the pressure regulator just in case. I figured even if that wasn't it, I'd probably replace it anyways with a new pump. Turns out that made no difference, so I ended up dropping the tank and putting in a new ACDelco pump. Problem solved.