JUST CHANGED THE ENGINE IN MY 2001 DODGE CARAVAN 3.3L AND GOT A 2002 3.3L REPLACEMENT FROM A JUNK YARD, HOWEVER SINCE I CHANGED THE ENGINE IT IS REALLY SMOKING A LOT AND THE GAS SMELLS REAL STRONG. I WAS TOLD TO CHANGE THE FUEL PUMP WHICH I DID AND NOW I AM ALSO TOLD TO CHANGE THE COMPUTER. I HAVE HAD THE PROBLEM PREVIOUSLY CHANGED THE OXYGEN SENSORS, CAN CHANGING THE MAIN ENGINE COMPUTER REALLY HELP OR IS THERE ANY DIFFERENCE BETWEEN THE 2002 AND 2001 3.3L ENGINE AND COMPUTER OR THE WAY THEY OPERATE AND COMMUNICATE WITH EACH OTHER MAP SENSORS ETC. I DID HAVE TO REMOVE A PIPE FROM THE OLD ENGINE AND PLACE ON THE NEW ONE WHICH IS 2002 AS THIS ONE HAD THE SECTION BLOCKED THAT RUNS A PIPE FROM THE TOP OF THE ENGINE TO THE SIDE WITH SOME SENSOR OF SOME SORT ON IT
AND ADVISE WOULD BE GREATLY APPRECIATED

 

well humm sence u have changed a few things this will be fun.
The pipe i will be was the EGR tube and stuff. Does the pipe on the old engine go from the top to the side where the belts are above the alt? if yes its the egr system. The 02 u have the engine did not require the egr because the 02 computer software took care of a mechanical egr. SO here is the catch to that u will need to get an o2 engine computer for the lack of egr mechanical system and not 100% if any other stuff changed software wise in 01 to 02. As for the fuel pump hehe u got had. The smoking is it white,black blue?

 

The smoke is black so you are saying that the 02 engine may have an electronic component that takes care of the mechanical egr that the 01 engine computer is possibly not operating. i would think that just by replacing the mechanical egr from the old engine and putting it on the 02 engine that the 01 computer would still work because the wiring for the 01 would then be different from the 02 and i would possibly need the complete loom as well?

 

Sounds to me that it is running very rich. My experience is primarily with GM cars, but I've never seen the EGR system affect the mixture that greatly. I'm assuming your new engine also has a fuel pressure regulator--is it hooked up? Is there a chance that there was a change in fuel injectors and related calibration between 01 and 02? Usually a sensor failure or disconnect will cause the computor to operate in open loop or back up mode which would still not cause such a rich mode.

 

Black smoke is yes fuel, Did u change out the wire harness as well or is it still orginal? There are plates or sealed up egr locations so i dont think u can just install the old egr system.. Yeah if the new engine did not hae the ERG installed then its done via software. I looked up an 01 PCM and an 02 PCM and they are different part numbers an 01 is either 4727401AF OR 4727407AF and 02s are 4748422AD WITH EGR AND 4748422AF With no egr so u need to have the correct pcm for the correct engine u have installed which i would go with the 4748422AF with no EGR.