Ruff Idle and or missing/ loss of power

Assuming you know how to test automotive electrical circuit's ,test main power (battery + voltage ) & negative grounds ? Voltage drop test PCM power an grounds . check battery voltage , charging (alternator ) system .
Charging System Problem Voltage Drops
Electric Testing Techniques You Need to Know

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PCM power and ground testing avi

First was it doing that before you changed the timing chain and second I have a 2005 Ford escape that was doing the same.I found some vacuum lines that had some small cracks in them so check all the vacuum lines and see if that helps.Good luck

Change the spark plugs end wires. One bad plug or a wire can cause a miss like you wouldn,t belive. Evan on a vehicle with low miles on it.

check for clogged egr valve.

P0121 The Throttle position sensor is a potentiometer that measures the amount of throttle opening. As the throttle is opened, the reading (measured in volts) goes up. The powertrain control module (PCM) supplies a 5 Volt reference signal to the throttle position sensor (TPS) and usually a ground also. A general measurement is: at idle = .5 Volts; full throttle = 4.5 Volts. If the PCM detects that the throttle angle is greater or less than it should be for a specific RPM, it will set this code.
Potential Symptoms Symptoms of a P0121 trouble code could include:

• Malfunction Indicator Lamp (MIL) illumination (Check Engine Light or Service Engine Soon light)
• Intermittent stumble on acceleration or deceleration
• Blows black smoke on acceleration
• No start

Causes A code P0121 may mean that one or more of the following has happened:

• TPS has intermittent open or short internally
• Harness is rubbing and causing an open or short in the wiring
• Bad connection at the TPS
• Bad PCM (less likely)
• Water or corrosion in connector or sensor

Possible Solutions 1. If you have access to a scan tool, see what the idle and WOT (wide open throttle) readings are for the TPS. Check if they're close to the specifications mentioned above. If not, then replace the TPS and re-check.

2. Check for an intermittent open or short in the TPS signal. To do that, you can't use a scan tool. You'll need an oscilloscope. The reason is because scan tools take samplings of many different readings over just one or two data lines and can miss an intermittent drop out. Hook up your oscilloscope and watch the signal. It should sweep up and down smoothly with no drop outs or spikes.

3. If no problems were noticed, perform a wiggle test. Do this by wiggling the connector and harness while watching the pattern. Does it drop out? If so, replace TPS and re-check.

4. If you have no TPS signal, check for 5 Volt reference at the connector. If it's present, check the ground circuit for open or shorts.

5. Make sure the signal circuit isn't 12V. It should never have battery voltage. If it does, trace circuit for short to voltage and repair.

6. Look for any water in the connector and replace TPS as necessary.
P0068 Symptoms - Engine Light ON (or Service Engine Soon Warning Light)
- Lack/Loss of power
- Engine rough idle Possible causes - Large vacuum leak
- Leaking air duct system
- Mass Air Flow (MAF) poor electrcial connection
- Manifold Absolute Pressure (MAP) poor electrcial connection
- Faulty Mass Air Flow (MAF) sensor
- Faulty Manifold Absolute Pressure (MAP) sensor
- TP sensor not seated properly.
- Faulty Throttle Position (TP) sensor.
- Dirty throttle body
When is the code detected? The Powertrain Control Module (PCM) monitors operation rationality check by comparing sensed throttle position to mass air flow readings
P0068 DODGE Description The Powertrain Control Module (PCM) monitors a vehicle operation rationality check by comparing Throttle Position (TP) to Mass Air Flow (MAF) readings. If, during a self-test, the comparison of the TP sensor and MAF sensor readings are not consistent with the calibrated load values, the test fails and a diagnostic trouble code is stored in continuous memory.

Hi, basically that means that there is an interal fault in the Powertrain Control Module (PCM). There have been many reported PCM failures on Chrysler/Dodge products although it is possible for this to happen on any vehicle. In Dodge/Chrysler products, a P0601 trouble code means that a serial communication failed inside the computer at least 6 times. In most cases means the PCM has gone bad. This is possibly due to a short-circuit inside the PCM. Or, if you disconnect the wires/connector from the PCM while the battery is still connected, that may also cause this code. The most common fix is to replace and reprogram the PCM. In a few cases the dealer may be able to reflash the PCM and get it working. But more than likely the PCM will need to be replaced and reprogrammed (we recommend you take it to a dealership for this). The good news is it *may* be covered under your emmissions warranty. So even if you're out of bumper-to-bumper warranty or powertrain warranty, check your warranty guide or dealer to see if this is covered.

fuel filter?

Loss of Power, too?

Burnt Valve! My guess - cylinder 3.

p0300 tells you the engine is missing .. the p0108 is the MAP sensor circuit .. MAP is "Manifold Absolute Pressure" or in simple terms it measures the vacuum in the intake manifold .. you could have a broken vacuum hose, bad power brake assist diaphram or other vacuum leak .. or you could just have a bad MAP sensor .. other less likely causes can be a timing belt slipped a cog ... listen for the hissing caused by a vacuum leak .. you can test the MAP sensor .. it should put out less than 2 volts idle and over 4 volts key on but engine not running (same for wide open throttle) .. if there is a vacuum leak then it will read high at idle .. if the sensor is bad the voltage may not change ..

Before changing you pcm try cleaning your egr valve. remove the valve and see if its stuck in the open position if so use a small pick to clean around the spring.