I have a 97 blazer with the 4.3. My blazer runs fine for about 5 miles and then it will not take fuel. It will idle fine but you cant give it gas. If you turn the engine off for about 10 seconds and then start it back it will be fine for a few miles then it will do it again. Ive replaced the plugs, wires distributor cap, crank sensor, rotor button, module, coil, spider, fuel regulator, throttle position sensor and cam sensor in the distributor. Could this thing be a little out of time? Im not getting any codes. Any help will be appreciated.

 

Sounds Like the Fuel Pump or a Clogged fuel Filter? When you turn it off it (pump) repressurizes good again for a little while. Have you checked the Fuel Pressure ?

 

I changed the filter and the pressure is 54 hot at idle and 60 when you give it gas. The fuel pressure is the same when its acting up as it is when its running good.

 

Damn thats alot of parts!!! the only thing else i can think of is the ICM (Ignition control module)

 

Are there any codes present? This sounds like there is a sensor problem that causes drivability concerns once the PCM goes into closed loop.

 

Engine light came on today. Gonna read the codes and Ill post them later today. Is there a way to make this thing stay in open loop to see if it makes any difference?

OK, the only code it gave was PO131 O2 sensor circuit low volts. Will this cause this kind of drivability issue?

 

Yes, it can. Please read P0131 Explained.

 

O2 sensor low voltage means the O2 sensor is consistently reading a high concentration of oxygen in the exhaust meaning that the bank is running lean. In this case, it is the driver side bank that is running lean.

Here is the code description:
P0131 - HO2S Circuit Low Voltage Bank 1 Sensor 1
That code is P0131 (zero after the P, not 'O').

Yes, it can cause driveability issues.

Do you hear any exhaust leaks?

How about vacuum leaks that would be near the passenger side of the intake plenum (runners that feed the driver side of the engine pull air from the passenger side of the intake plenum)?

Have you pulled the plugs on the driver side to see if they look like they are running lean or rich? A lean condition at the plugs would mean that there may actually be a problem with fuel supply to that side or a vacuum leak allowing more air in than the PCM can account for. A rich condition at the plugs would mean that there could possibly be an exhaust leak between the O2 sensor and the engine causing a false lean condition that is actually causing an overly rich mixture in the cylinder.

 

Replaced the o2 sensor and still didnt fix it. Has anyone ever tried to put a carb on one of these things? Im getting tired of fooling with this thing. It belongs to my parents and they need it to go to the dr and its been down for a month. Ive replaced just about everything. It just keeps running lean. I even put new intake gaskets on. Summit racing has carb intakes for these has anyone tried it?

 

Anyone??????