I don't know what the diverter valve is either. But any way, did you try driving with the pre cat o2 sensor unscrewed from the pipe?

 

The o2 sensor kept stripping so instead of ruining it I just in plugged it. No light came in the truck wasn't backfiring as much as normal. But everyone and awhile the truck will run ok. It did die as I slowed down at stop sign and it only does it once and awhile. Maybe my timing is off too ? It didn't really missfire like before it does shoot the cel light on and off with rpms jumping but doesn't jerk and go crazy. Also noticed if I push throttle no matter how much I can watch the fuel gauge just dump down like it's eating to much gas.

 

Sorry, but you need to get the o2 out. (Needs replace anyway) You need to eliminate certain things from the fray. Otherwise we are all just spitting into the wind.

 

My other thought would be the crankshaft position sensor. It has all if those symptoms. And I'll try and get it out

 

Start the motor and get it up to temp, sometimes that helps with getting the o2 unscrewed. And 9 times out of 10, when the cranks sensor is bad , it just stalls while driving, wait a minute and it starts.

 

It will stall when driving or when slowing down at a stop sometimes it will not stall. It's hit and miss. And I can throw it in neutral and it will start up.

 

Until you remove the O2 from the pipe and do the other things that have been suggested, I'm done here, let us know the results after you do those things .

 

Just did the drive with the o2 out it ran a lot Better one backfire. No missfire or lurch. When 65-70 just fine. An up hill did just fine.could this be the fix

 

Cat is clogged. If you don't have emissions testing where you are, you can just cut it out, weld in a pipe, and call it a day. If you DO have testing, have to replace the cat. Get one from magnaflow. They have high-flow, direct-fit cats, that will bolt right in in the stock location.

Then you need to find out WHY the cat clogged, more than likely burning oil from the blown plenum, need to fix that, and then replace the front O2 sensor as well.

 

Going to see if my buddies uncle can hook me up with a straight pipe system for cheap. And I've bought the new 02 sensor. I've replaced a good amount of stuff so far plenum will be my next one. Thank you guys for all of the help.