My 2000 5.3L V-8 has begun to start with difficulty. Takes several attempts before engine "catches". Starts cold ok, but think there's a problem with the injection system during the start cycle. 91K miles. Ideas? Thanks

 

Might be some fuel injector cleaner might help your issue.

 

Had just run Techron thru it several weeks prior to the problem, Thanks

 

What was the cure for this issue? I have the same issue with new fuel pump and regulator already installed.

 

I changed out the right side check valve. Helped a little, the problem isn't gone altogether.

 

A check valve in the fuel rail or where?

 

I'm pretty sure they're called "exhaust check valves". There are one on each side, they come from the exhaust manifold on both sides via a metallic tube, then each valve goes to a tee, then to a canister on the right rear of the engine compartment. On RockAuto.com it's called "Air/smog pump check valve".

 

I would recommend checking the fuel pressure. I had an issue very similar to this in one of our vehicles and it turned out to be a weak fuel pump. It would start great when cold, but after it had run for a little while, the fuel pump would get weak. I had a very difficult time diagnosing the problem because the fuel pump was not that old and reckon I changed out every sensor I could think of trying to chase it down.

Just something to consider.

 

I agree with Mark. My truck would start easily when cold, but after 20 min of running then shutting down..it would take 2 to 3 attempts to crank before the engine would finally start. Sometimes just turning the key on (Not starting) and hold for 10 seconds then crank would work. Turns out, it was my fuel pump. Although running fine and strong pressure when tested, it was after letting it sit warm after 15 min the pump/pressure would be very weak resulting in tough to start. So replacing the fuel pump was the fix for my starting issues.