My 98 has been having power problems for quite some time now. After a compression test and finding very low readings I pulled the engine for rebuild. Found the reason for low readings to be broken comp rings on 2 cylinders. Bored block .030, had crank turned, head shaved, and had valve job done. Put it all back together with new injectors, TPS, IAC motor, and Mass Air Sensor. It runs far better than before. the problem is that it shill has no top end power. Hooked it up to scan tool and at idle it shows the ign timing to be at -3 deg even though a timing light shows +8 - 10 deg at balancer. Checked another 2.5L Ranger with same scan tool and it showed +12 deg ign timing while at idle (did not check this one with timing light). I am old school (don't know much about computer controled engines) but I know that if timing is retarded you get loss of power due to it. I think this is the problem I am having here but don't know how to change the ign timing or why scan tool and timing light would show different values. I can give more detail about problem but didn't want to muddy the waters too much at first. I am really stuck and need some help please.