Disconnect the pre-cat O2 sensor, and drive it that way for a bit. (it will set a code....) if the problem goes away, replace the sensor.

 

Oh yeah, you're talking oxygen sensor now.

It's the one closest to the engine. The one behind the cat is used only to keep an eye on the cat to make sure it's working, but the one in front of the cat is used to monitor the exhaust for setting the fuel mixture. When these sensors get old they'll read too rich until they're a bit hotter, so the PCM leans up the mixture to compensate -- not good at all. When you revved the engine you threw more hot exhaust gas at the sensor, warmed it further, and it came into more or less normal operation.

Don't fool around with it, just replace it. The risk of cracked heads (due to excessive combustion chamber temperature as a result of a too-lean mixture) just isn't worth it.

 

Did you replace the plugs? How old are the plugs that are in the block?

 

Plugs are fairly new, now even a year. Yupp, it was the O2 sensor. Put a new one in and its fine now. Thanks all!

I also swapped in an extra set of wires I had (had to buy the whole set after I melted my coil wire on the block a while back) so I threw them on when I put the new cap and rotor on.

I read that 8 to 8.5 wire are the best. The ones I took off were 8mm and these new ones I put on are a bit smaller in diamater then the 8mm ones I took off. Will this really effect the performance at all?

 

Glad you got it fixed!

If you're not getting cross-fire or arcing, you're good. Plug wire routing is more important than insulation diameter, but with a greater insulation diameter you can get away with sloppier routing.

 

Oh, damn. Well, I didn't get any spacer/holder pieces with these wire or if I did I lost them.

But I just bundled them all together and zip tied them up away from the manifolds. Is that bad. You don't want them to be touching eachother?

I wasn't useing my head. I suppose.

Any symptoms of arching or crossfire? (poor acceleration) Anyone have a wire routing diagram? Is it even possible based on the F.O. of our trucks?

 

Not good/very bad!

Cross-firing will often result in backfiring or preignition, missing, stumbling, that kind of thing. Arcing will cause missing/stumbling.

Here ya go.


Inductive cross-fire? Oh yeah, it certainly is, especially between cylinders 5 and 7.

 

Spacer clips are easy to come by at any parts store. Routing seems to be very important per the link that was provided ( I have a copy taped under my hood so I don't have to look for it when I install modified intake, plugs, rotor, and wires as well as other work I'm getting ready to do on engine).

I would fix that before you start having problems.

 

............

 

Well, I made some spacer pieces out of hand fulls of zipties last night. Thanks for the wiring diagram thou. I'll have to wire it all up properly this weekend.