Stalling Under Throttle

Checking the fuel pressure would be a great place to start then go from there.

Well, I will give my experience for consideration. My old truck had sat in the dessert for a couple years before I had it shipped to Texas. Luck would have it, I charged the battery (wal-mart) and changed the oil and started driving it. After a couple months under hard acceleration my truck would cut out hard, then kick back on. First I thought trash in the tank and all the stuff I would have to do to fix that. Instead I went the route of plugs/rotor/dist. cap/and wires. Problem solved. She has been running like a champ for the past 2k miles. Acceleration is up to the point of barking the tires, which was not something the truck was doing before the new parts mentioned above. ( can't believe that damn cheap walmart battery could go for so long completely dead, charge it and been running the truck for 2 years with it) LOL! Any how that is my experience for the past couple years. Running good enough for now...but researching a LS swap hopefully to happen in the next 12 months.

Possibly defective fuel pressure regulator.

-lee

I'll add my fuel related story, my was hard starting cold, I would have to use the ether spray to get it to start easy, other wise crank and crank and crank, you get the idea. Warm less than two hours after shutting it down it would start easy. If I kept my foot out of the throttle, under three thousand RPM it was OK, but if I ask for more it would fall on its face.

I finally got around to having the fuel pump replaced, the place I took it to saw me coming and a sucker at the same time. Over $900 dollars parts and labor, they even charged me around a $100 to find out what was wrong and wouldn't roll that into the final cost of them fixing it. I was told later by a different repair shop that I paid about $300 to much to get it fixed, but they did verify that the pump that is needed for my 98 5.7L cost around $400 ish dollars.

The short version is, GM had a stupid idea and for a couple of model years, designed them so they need right at 60 PSI fuel pressure, give or take only about a couple pounds variation to run properly. It now runs fine at any throttle and starts after only a couple turns of the starter.

I had a similar problem that turned out to be a defective spark plug (hairline crack).

Seemed OK at low RPM but when accelerating it would surge.

Hey all I should of come back here earlier. It got so bad to the point I couldn't leave my driveway barely, I could idle around and barely give it throttle. So this weekend I replaced the fuel pump. Did the ghetto way out and cut a hatch, was going to pull the bed but took one look at my rusty/corroded bolts - all of them were terrible. Needed the truck to go pick up a hood for my TA that day and it was Sunday morning so I just made a hatch and took the square piece I cut out and added weather stripping and some hinges and put it back into place with some self tappers. Then gave it a couple small spot welds that could easily be popped apart in the future if needed. Should still be strong enough for anything that might sit on it in the bed.

Runs perfect now, drove it 4 hours total picking up my hood.

Redneck ingenuity saves the day.