What spark plug work best with 8mm wires? The truck has 270k andhad it a year

 

Just get cheap copper plugs, it came with Champions.

270,000 miles or kilometers?

 

Could bad wires be the problem

 

YES!

Bad plugs and wires is where I would start.

The GEMS engine has default settings for everything, so if the cam sensor fails, the engine will still run.
Crank sensor fails...still runs.
TPS...still runs.
It will run like crap, but it will still run.
With that in mind and with the price of those parts and and the difficultly replacing those parts when ever working on a car remember this.

K eep
I t
S imple
S tupid

In other words, start with the simple/cheap stuff first, like plugs and wires.

 

Ok I'll replace the wires and plugs and let you know.

 

the camshaft sensor is located on the timing chain cover below the water pump ant the crank sensor should be on the side of the eng towars the back near trans.

 

One of my spark plug wires broke off right at the plug, they were Lucas, most likely original set from 1997.

 

same here