305 vortec running rough.

[NaturalGasForcedAir]

96 305 vortec. New o2 sensors, plugs, wires, fuel pump.
It misses under load and idles rough. I pulled the egr valve and cleaned. I also tried unplugging the egr valve while idling, It made no difference. The egr tube is cut off and open to the air. The truck has been sitting for 6 months with no battery, it has a new fuel pump and fresh gas.

Any help would be great.

 

[inthechateau]

Take a lok at the rotor button, I've had a lot of problems lately with them arching to the mount screws.

 

[SAATR]

Take a lok at the rotor button, I've had a lot of problems lately with them arching to the mount screws.

I agree that an inspection is in order. Probably should just go ahead and replace them with new quality units, as the crab cap the Vortec uses seem to be especially sensitive to corrosion, and have a tendency to start cross firing with age.

 

[Keepinitoldskool]

Inspect all ignition parts and post back with your findings. Condition of spark plugs will tell alot. Label to plugs with a sharpie as you remove them so you know what cylinder is suspect later on. Last time I went off my "memory" I ended up replaving the wrong fuel injector lol.

Sent from my SAMSUNG-SGH-I537 using Tapatalk

 

[michael hurd]

Check the coolant level. If the level is low you may be leaking coolant into the engine oil. Besides the coolant temperature sensor getting a whacked reading this will cause a myriad of issues. Did it run properly prior? Is this something you recently purchased? If the coolant level is ok and the engine oil is good I would pull a compression test to check for bad cylinders. If good then change the distributor cap and rotor.

 

[michael hurd]

Are you certain that the plug wires are correct?

 

[NaturalGasForcedAir]

plug wires are correct, plugs look good, no coolant in oil, none of the gauges have worked for years so im not sure if the coolant temp sensor is wrong. So are you saying to replace the rotor?

 

[SAATR]

plug wires are correct, plugs look good, no coolant in oil, none of the gauges have worked for years so im not sure if the coolant temp sensor is wrong. So are you saying to replace the rotor?

Inspect first. If there is any doubt, replace both as a pair.

 

[Keepinitoldskool]

If all the plugs looked fine and no discoloration I would be checking the coil, fuel pressure, and compression.