We have a 2002 Dodge Caravan, 176,000 Kms, 3.3 Litre engine. For a couple years, I have had large leak & small leak engine codes, I had 2 smoke tests, but they could not find anything. I recently noticed radiator fluid low, so I had that checked out, and they said the air intake manifold gasket was gone. Prior to taking it in for that, it started running rough when cold, as if choke was not on. After the air intake manifold gasket was installed, the van now runs rough when warm at a complete stop, at 600-700 RPM, it sometimes runs at 800 RPM and that is smooth, but then it goes to 600-700 RPM again, it feels like it is about to stall, but once you apply gas, it runs great. Below are all the codes that the van is giving me. I also had all new plugs installed when they did the intake gasket. Any thoughts ????

P1294 - TARGET IDLE NOT REACHED
P0135 O2 Sensor Heater Circuit - Bank 1 Sensor 1
P0301 Cylinder 1 Misfire Detected
P0442 Evaporative Emission System Leak Detected (small leak)
P0455 Evaporative Emission System Leak Detected (large leak)

 

Welcome to DF
The target idle not reached code.How does the van run in park? Also put a vacuum gauge on the engine and see if you are loosing engine vacuum.An o2 sensor will give a poor running problem and so will a misfire. If you have ck all your hoses,then replace the vent valve thats near the LDP pump.