2004 H2 running rough???
 

I have a 2004 H2 that has started running rough at higher speeds....it feels like it is missing or something. It hasn't pulled a code, so I don't think it is the O2 sensor...any ideas of what it may be? Spark plug? I am hoping to figure it out before it gets worse....

Re: 2004 H2 running rough???
 

Could be plugs or wires. How many miles? Easy way to check wires is open the hood in the dark with engine running. If they are shorting out anywhere you'll see blue sparks. You should hear it too.

Another thing, how about the fuel filter? That is something that shows up at higher engine speeds. (needs more fuel)

Re: 2004 H2 running rough???
 

Thanks....both easy to check and easy fixes! Appreciate it, will look tonight!