I have 1997 Chevy 2500 van with a 5.0 and the will on run at half power until it warms up and then it takes off. It has 115000 miles. I put new plugs wires coil distributor 2 o2 sensors and fuel filter. The code coming up now is po307 number seven misfire. Checked wire on tight and new. Any ideas why runs half power then go real strong after it warms up.


Thanks

Peter

TxGreaseMonkey

Thoughts:

. Check/replace the Engine Coolant Temperature (ECT) Sensor:

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ECTs affect fuel injector pulse width. The ECT Sensor is a temperature dependant resistor (thermistor), whose resistance decreases as the engine coolant temperature increases. It provides a richer mixture when cold, leaner mixture when hot. They become corroded, due to not changing the coolant frequently enough, flood the engine, and waste a tremendous amount of fuel.


. Have you ever replaced the Ignition Control Module (ICM)? Here's what it looks like and costs:

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