I just replaced the fuel pump on my 99 S10 Blazer with a new Delphi fuel pump. It started right up after that,and ran fine. I started it two or three times after that (I was doing the rear brakes at the same time,since I had it up on jackstands). I noticed the 'check engine' light came on,and it was code P0452. I turned the car off,and when I came out to start it again,It will only crank-no start at all. A fuel pressure gauge shows 60psi,and it holds close to there after the key is turned off. Where should I start looking for problems?

 

General no start diagnosis. If you have some starting fluid, spray that into the throttle body and see if it will start. Having pressure is only one side of the equation for fuel. If the injectors are not opening, that pressure means nothing.

If it still does not start with starting fluid, then it may be a spark issue.

The intake duct work is still connected properly right? The engine will not run with the MAF sensor plugged in, but the intake duct disconnected at the throttle body.

 

Well, hmmm... It's running out in the driveway now. I sprayed starting fluid in the "carb",put the intake ducts all back together,and after cranking for maybe 15 sec, it caught and started. Now it's idling just as sweetly as ever. I shut it off and it restarted immediately.

 

Did you change the fuel filter when you did the pump? Maybe a piece of debris made its way through the system and momentarily clogged something?

 

yes, I changed the fuel filter when I had the gas tank off. I was almost surgical in my obsession to keep anything from falling in the gas tank-especially when I was hooking up the filler neck again. I cleaned the frame ground point up with a sander,too. I've started it several times again with no problems,so I just don't know what got into it-I was so disgusted,thinking I might have to pull the tank again,so let's hope it was just a momentary thing. I'm going to stick close to home until I'm sure,though.

 

Still having problems, I guess. I went out to start it this morning,and it would only crank. I sprayed more starting fluid in it, and it caught, ran rough for a few seconds,and then settled down into a good ,smooth idle. Any thoughts on what might still be wrong?

 

Well, I hope this is a final update to the problems I've been having with this truck. I've had it since it was new in '99,and it has almost 100,000 miles on it. (I have other cars, so it doesn't get used all the time-that's why I have been taking my time working on it)
I was still having problems with it cranking a long time before starting,and the other day, it just wouldn't start at all. I kept thinking the fuel pump I just put in wasn't installed right, but the pressure checks came up good. I was searching through all the "fuel pump" threads here to get some clues as to what to do next, and came across one that sounded just like my problems-it turned out to be the rotor and distributor cap-just like that person found out-I took mine off, and the contacts were badly loaded up with deposits,and the rotor tip was burned, and coated with a green deposit. I changed them for new Delco parts,and replaced the coil while I was at it-the truck started right up! I sure hope this is it-this is the first problem I've ever had with it. I probably changed the fuel pump when I didn't need to-I just guessed at the symptoms,and I didn't have a pressure tester at the time. After 10 years, it was probably due for a change anyway. This forum has been very useful to me-I hope this thread can be of use to someone else with the same problem.

 

Those seem like the most overlooked items on our vehicles. Mainly because they are in an awkward place and a pain to change. I know mine probably needs it too.