Mike_the_fireman

Just recently returned from overseas and getting my Z71 back in running condition. Wife was suppose to start it weekly and that turned out to be an epic fail. Replaced all fluids, battery, brake booster and charged the AC. Went to the gas station to fill the tank and then topped off the tires at the air pump. Then the problem started...when I put the truck in gear to pull away the engine stalled. Engine will crank over but not fire. Quick burst of starter fluid and engine will start. Will idle but when the gas pedal is pressed the engine will stall. I was able to get back to the house at idle but still have the issue. Will not fire unless a burst of starter fluid is used. Will either idle or run at high rpm's when the gas pedal is pressed. Back to idle and then will stall when pedal is pressed again. Fuel pump is running and replaced the fuel filter. Truck will idle all day long if gas pedal is not pressed. Will also die if I engage the AC putting a load on the engine with the compressor.

Any other thoughts as to the issue? Plugs, sensors, etc? Was running fine prior to filling the tank (with the proper fuel). Also added Gum Out Fuel Injector cleaner when I filled the tank. I had added fuel from a 5 gallon gas can to drive around town and get me to the gas station the few days prior to the issue.

Any and all suggestions and information would be greatly appreciated.

Vehicle info: 1998 K1500 w/250K miles. 350 Engine replaced by dealer at 170K when it seized.

wmiller1337

My money is on the fuel injection spider.

shamrock246

how long was it sitting?bad fuel could be clogging your new filter,whats the fuel pressure? E10 phase seperation is causing some major problems in the marine industry unless its jacked up on stabil,if you have the old style injection sider and find a problem with it i would toss the whole thing and get the upgrade i found mine on amazon forabout $215


Sean

97 4x4 burb

Mike_the_fireman

I was thinking injectors also and had added the injector cleaner during the fresh fuel fill-up. Changing the fuel filter revealed little results with some small particles in the filter when tapped on the ground. A little more research and looking at a fuel pump at the parts store reveals a small particle filter on the bottom of the pump. Going to guess that with filling the tank from the gas station, I stirred up any sludge on the bottom of the tank and clogged the filter. Going to pull the tank, clean and check the pump filter. Unfortunately the pump filter is all one piece with the pump and has to be purchased as a unit.

Truck was sitting for 8 months with only the ocasssional starting of the engine.

stew160

Sounds like you are on the right track. Ethanol in gas is causing many problems. Regular stabil does not help. Must be specifically for ethanol fuels.
On a possitive note, the filter is doing it's job. Otherwise all your injectors would be plugged. Good luck!

macintosh894

Check the Fuel pressure regulator under the upper intake manifold . It regulates the flow of fuel to the injectors . Its a 60 to 70 dollar item and requires the upper intake to be removed . its a small device that hooks up to the side of the injector housing .For the 1998 they put the injectors in the upper intake which is an odd place to put them they get oil on them and get gummed up and sometimes need an injector cleaner or need to be replaced . Very bad place to put an injector and hard place to get at under the upper intake .

macintosh894

The injectors are now out in the open on the side rails near the plugs on newer models

macintosh894

They tend to bury stuff in hard to get at places like the Injectors and the fuel pump

macintosh894

Should check you fuel line pressure from the pump to the fuel regulator which is under the upper intake manifold On the motor up on top on ECM side there is a fuel line with a port on it to check fuel line pressure . Fuel pump has to have 40 to 60 pounds aprox. to operate the injectors . It verys with the model of vehicle . The chevy fuel line requires a GM fuel line pressure tester . or can get a kit from Harbor Freight to work on it . I have changed the Fuel filter on mine ,Fuel pump and Fuel regulator . But not the injectors yet . The Fuel tank has to be lowered and fuel pump replaced and its a major job doing this . Us a a OBD II tester which plugs in under the steering wheel and will give you a read out of the ECM problems like Left bank lean and will give you an idea what may be the problem . OBD II is a sacnner like device and reads the on board computer . When Check Engine or Service Engine light comes on Plug the OBD II in and check for problems . I have had lean fuel code on right bank and then used a injector cleaner to fix the problem .

Mike_the_fireman

Pulled the fuel tank and replaced the fuel pump. The inside of the tank was pretty clean with some small particles but nothing that I would be concerned about. Fuel pump filter did have some sediment. Long story short, replacing the fuel pump was the fix. Guessing the small amount of fuel that was still in hte tank was agitated by the tank fill up and clogged the fuel pump filter. Ran around town with fresh fuel and then replaced the in-line filter with the second I had purchased.

Thanks everyone with the information and advice.