If a 2000 GMC Safari stopped running and now will turn over but not start what is wrong?

Additional

I had the same problem and it was fuel pressure. GM products are very sensitive when it comes to fuel pressure. You can be only a few pounds of pressure low and it will not start. I would check it first. There is a testing port on the aft top part of the the engine. Remove the interior engine cover/hood and check it. If the van was running and now just won't start, this is agood place to start.

Note: The sympton with my van was it started but started to require a few trys to get it started....then it required 4-5 trys. Eventually I could not get it started. If I was able to get it started it stayed running and ran fine.

At the risk of sounding like my dad, any internal combustion engine requires three things to run: -Fuel -'Fire' -Compression

Sounds as though you're looking at the most likely problem areas.

Some additional input:

-Fuel: Just because you replaced the fuel filter, that doesn't mean you're getting fuel. If you've replaced all that other stuff without blowing anything up, try disconnecting the fuel line at the point where it enters the carb/injector system, stick a can or fuel-proof container under the end and try cranking the engine a couple times. If nothing comes out, you've got a bad fuel pump. (As previously mentioned in some of my GM related rants, the fuel pump is in the gas tank. Good luck.) -'Fire': Using a thick glove or rag, disconnect one of the plug wires and hold it close to the engine block while someone cranks the engine a couple times. If no electrical flash between the plug wire and ground, you're still missing something in the ignition system. -Compression: Probably not an issue, unless you've already confirmed you've got fuel and 'fire'. Even with a blown head gasket, the thing should try to fire and maybe even run-roughly.

First thing DONT EVER hold the spark plug wire with any part of YOU when cranking over the van or any car .if it there is a very high voltage that can kill you before that the easyest way to test the fuel pump is to have somone turn the ignition to on not to start just till the radio wiper work but of couse have them turned off so you can hear . listen right at the gas refill door if your FUEL PUMP is working you will here it prime for startup.. If you dont here anything then start cheking fuses if all fuses are ok then your pump is fubar Iv had to replace mine. Just remember its either gas or electrical that will stop your vehical from starting .After rereading your Q if it starts and runs and stops and will not start again that sounds like the FUEL FILTER had that happen to me too. The fuel filter when cold at first start it allows fuel threw butt after fuel passing threw the filter heats up by friction and swells up making it inpassable IE no start but engine crancks but wont start that is the first thing to check from what you discribed good luck