so my uncle has an 02 4.0 edge and he came over telling me he had some problems with his truck so i took it for a drive.


takes off blogging way down. and when it finally decides to pick up speed around 45mph when the rpms hit 3200 theres a mean misfire. kinda makes the truck lunge a bit forward.

i dont know very much about these 4.0.....anyone got any ideas?

 

Check the plugs and wires? How old is the fuel filter? Will the truck rev past 3200 when driving?

 

missfires generally pop a trouble code. Are you getting a light?

 

I suspect spark plugs or spark plug wires. I had something similar to this after installing new spark plug wires. It ended up being a spark plug wire that had not snapped all the way in place on the plug and came partially loose. It did not misfire until it got to higher rpm under load. I suspect bad spark plugs of wires would react similar.

 

X2 a missfire condition will flash the CEL while its happening as well