I have a 98 ranger that has been having issues that can't seem to find the problem. It's the 4 cyl 5 speed manual has 194,000. Truck has very little power and check engine keeps reading EGR. I have replaced egr valve, egr vacuum pump, egr line from manifold, all plugs and wires, both o2 sensors, both ignition coils, I have vacuum tested it, new exhaust from manifold back I have no idea what it could be. I've taken the throttle body off and cleaned. Truck just doesn't have any power. I've also replaced fuel filter. Timing was done about 3 years ago when my dad owned it. Last week started to get arching from one of the coils to air filter hose. Put the old coil back in and seems to have fixed the arching problem.
And ideas or thoughts would be greatly appreciated.

 

Welcome to FTE.

You've been busy on this one & with the mileage on it you may have more than one problem. Good find on the arcing coil, that is a common problem on those parts.
With the hood raised, you could idle the warmed up engine after dark & with a spray bottle of water & one at a time spritz the coil packs, wires, & plug boots, while looking for a arcs & sparks light show, to find weak or faulty insulation. If you still suspect electrical breakdown, the coil packs are known to crack underneath & arc unseen, so raise each coil pack & give it a spritz underneath too.

Were all the other items you replaced testing bad, or were you tossing them at a problem & hoping for joy?

With the mileage on this puppy a number of important scheduled maintenance items are due for replacement & the timing belt you said was replaced a couple of years ago is one of them.
Other maintenance things that come to mind that'll cause wimpy power at throttle up are air & fuel filters, worn out PCV valve that can let blow by foul worn plugs, faulty plug wire insulation yielding wimpy spark, a clogged cat converter, or restricted exhaust, worn out O2 sensor, all of which can make it wimpy on power at throttle up.
SO, tell us if the vehicle is up to date on it's scheduled maintenance replacement parts.

On the EGR question, post up the trouble code Number, as it could offer a clue of where best to look next at that systems components. Of that vintage, the DPFE sensor & it's connecting hoses & the exhaust feedback port below the EGR valve, that connects to the high temp hose that runs up to the firewall mounted DPFE sensor, are also common problem parts. If the engine is burning oil, the exhaust orifice below the EGR valve that the DPFE hose connects to, can become restricted, or clogged with carbon & that'll un-calibrate the works & cause the DPFE sensor to send the computer corrupt EGR control data. Same thing if those hoses are loose fitting, dry rotted & leaking vacuum, or exhaust.

A bunch of thoughts for pondering, post up All trouble code Numbers & fill the forum in on where the vehicle is on All of it's past & present due scheduled maintenance replacement items.

Post up All trouble code Numbers, as they can help focus a trouble shoot.