My blazer I bought used and drove from Phoenix to Vegas with no problem until I was 50miles outside of Vegas and it started stalling sputtering all the sudden randomly. I made it to Vegas and have replaced the distributor, rotor, coil, plugs, wires, MAP sensor, pressure sensor on intake, the intake sensor on intake, the edge valve, one of vacuums, fuel filter, and fuel pump and none of that has changed the fact that it won’t rev over 1500-1700 rpm without hiccuping and dying, what could be the issue? I am mechanically inclined but this isn’t making sense and I don’t know what else to replace without pulling out my hair. Is there another vacuum I don’t have attached that is essential for engine to correctly run? Any help is awesome thanks?

 

Start with fuel pressure and 10 min leak down key on engine off.

Do you have a scanner that can read live data?

Any codes?


George

 

I know it’s not holding fuel pressure at all even after new fuel pump, it’s immediately gone and getting a P00300, P00101, P00300, and another one but it didn’t change even after new pump and filter the engine idles rough but bogs bad when peddle pushed at all?

 

OK, given your fuel pressure leak, remeasure at the fuel filter so we know if your problem is down stream or upstream of the filter.

George

 

Try dumping a can of SeaFoam in the tank. I had a similar problem a few years back when I was on the road, and after the first five miles or so the problem was gone and hasn't returned. The alternative was to buy a truck and car trailer and tow the Blazer back home. Pretty sure my injectors were partially fouled by a bad tank of gas.

 

It has pressure up to the filter but as soon as I turn truck off I lose pressure immediately. Could the cat be clogged as for why it’s not running right?

 

That means that the problem is in the tank or the lines from the tank to the fuel filter.


George

 

Maybe I don't understand your answer and what you mean by turn the truck off. So what happens after the 2 second key on engine off fuel pump prime when measuring the fuel pressure at the fuel filter? Does it hold 55 psi for 10 min? You need to get your fuel pressure fixed before anything else like diagnosing cat function.


George

 

No it immediately loses all pressure in the rail and it defintely is starving for gas. i found out the return line which is connected to some regulator or sensor was clogged but still no pressure so getting banother pump.

 

I know that they are more expensive but gat a Delphi or AC Delco pump. The failure rate of the off brands are just too high.


George