Detonation and Injector Size?

[2L8ULUZ2]

I have recently started having detonation problems with my 94 sport and replaced the pressure regulator, o2's, and cleaned the MAF. I was also looking for any obvious signs of anything loose around the motor. I noticed that the injectors in it were definately red in color on the tops. Now assuming that all ford injectors are the same color this tells me that they are 30#'s since that is what I run in my mustang. They look identical being red on top and black bottom. I assume that the supposedly stock 19's are grey bottom and yellow/orange tops. We have had this thing since it was new and never replaced the injectors. So are these the standard color of all them in the 94 4.0 or do I need to pull the upper and stick the stock 19's from the mustang in it? About the detonation the above mentioned did nothing for it but I found that they stock fuel filter is still there and that is gonna be my next thing to replace. With 130K I am also thinking that there is some carbon build up on the pistons causing this. What is the most effective method of clearing this out of the motor? Most of my experience is with the 5.0L in the mustang but I know my way around motors and just need a starting point. Thanks in advance!

 

[Jason_25]

Your explorer has 19# injectors.

1.Clean the MAF with electrical contact cleaner.
2.Re-tighten the lower intake manifold bolts
3.Run a bottle of seafoam through the engine while it's running. Be careful not to hydrolock it. After doing this, drive on the highway at 3500 rpm for 5-10 minutes. That should get all the carbon out.l