Runs at half power till warm

[pbr3232]

I have a 1997 chevy 2500 with a 5.0 with 115000 miles. I just put new plugs wires coil ditributor fuel pump and two o2 sensors in it. I was getting codes for o2 sensors and now I am getting p0307 number seven misfire. As I said it has new plugs and wires. What I was wondering is why it would run at half power or barely run and then take off after a couple of minutes. The check engine flashes until it takes off. Any ideas much appreciated.

Thanks

Peter

[MT-2500]

What kind of plugs did you use?

307 is a engine misfire on no 7 cylinder.
Is no 7 plug getting good hot blue spark and is plug wet on end when missing?

Check all sensor readings and fuel pressure for up to par.

[pbr3232]

The plugs were ac double platium. I will check the pressure and spark. I had a mechanic put the plugs in but I will double check it. The rest of the stuff I read the codes and put in.

Thank for reply.

Peter

[MT-2500]

You are welcome and let us know how it goes.

[DFBonnett]

Originally Posted by pbr3232

The plugs were ac double platium. I will check the pressure and spark. I had a mechanic put the plugs in but I will double check it. The rest of the stuff I read the codes and put in.

Thank for reply.

Peter

Don't discount the possibility of a defective plug or wire, new or not.