Truck is 4 speed automatic. Truck acclerates rough through first and into second before smoothing out. Have replaced plugs, rotor, cap, fuel filter, pcv, exhaust system and transmission. What else can it be?
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wow a 99 an oldie but a goodie , one that old id be looking at all the vac lines , for pin holes,worn spots and cracks , a vac leak will make engne run rough at idle and as you acclerate the vac goes away so hole in hose does not matter
Check your vacuum lines and be sure your throttle body is tightened down. Carb cleaner spray can be used to find the leak. Spray it around the lines and gaskets (while the engine is running). If the idle speeds up, you found the area of the vacuum leak and the solution to your problem, possibly.
The age of your vehicle also guarantee's a vacuum leak. It may sound silly but the truth is rubber grommets, and hose's shrink and dry out over time and the harsh environment under the hood makes it worse. Check all vacuum lines and fittings attached to the intake manifold, valve covers (pcv valve), and be sure to check for a vacuum fitting on top of the intake just behind the throttle body. Does it fit tight in the hole? You can seal loose fittings with a high-temp RTV (Red) silicone sealant/adhesive. Several small leaks add up and your engine, heat/AC, and transmission will be all to glad to tell you about it.
You stated the engine smooths out when you let off the acclerator. That closes the throttle and increases vacuum in the intake manifold. The leak could be anywhere. On the engine, under the hood, in the dash, along the frame towards the rear, or at the vapor canister.
P0059 .02 sensor heater control circuit draw. 02 heater resistance What this means is the 02 is shorted or open or ECM . 2nd bank sensor one. What concern me is rough accleration,either the ECM subsituted a value to protect the catalytic or you do have a engine miss and P0059 under rationality ,logic appeared.I have to say your solution is to replace 02 sensor on the second bank.To find the second bank stand in front of the vehicle the valve cover closest to the front is bank one the valve cover fartherst from the front is bank two.
The codes you provided indicate separate issues. Code 1167 is indicative of either a stuck fuel injector of the O2 sensors. Code 0340 indicates the CMP position sensor. Replacing the O2 sensors will likely clear the 1167 code assuming the fuel injectors are okay. It would be the first course of action. If there's no noticeable change in performance (i.e. stalling problem continues) then the CMP position sensor is likely your overall problem. Best of luck. Greg