Originally p1381 check engine light on limp mode wont go past 3000 RPMs up and down up and down like clockwork..... Then I increase idle at throttle wheels from 7500 to 1000 RPM..... Idle screw out one and a half turns... now limp mode from 1000 rpms to 2000 RPMs only after warm up no check engine light I can live with this but I don't want to it runs like this consistently now I'm thinking about trying to run it without the heat sensor on or trying to mess with the idle screw or both thanks

 

p1381 - When that fault is present rpms are limited to 3000.
Poss causes:
-Corroded electrical terminals leading to the distributer
-Defective or weak Ignition coil
-missing or incorrectly installed ignition coil shield
-alternator diodes or regulator failing causing irregular line noise
-damaged sensor wire (usually yellow with a purple jacket where shielding begins.
-Defective ECM or PCM
-Faulty Cylinder Position Sensor.




I noted a couple cases via google where the alternator was the culprit. You can pull alt off and have it checked for free at Autozone.
(buy from The Zone or RockAuto)
After that I would inspect wiring, clean contacts and grounds.
Then replace CPS if issue still present.
ECU as last resort