Hi;my 2001 dodge grand caravan/sport has a serious problem with speedometer not working,runs for a little while,but then starts running rough,and will stall after i put it in drive.it,s a 3.3 ,3speed automatic.I did disconnect battiery when workong on it to change out the vss output,mybe I need to change input one as well???.need help asp,only vechicle to get to work,can,t use it now.can anyone direct me,or help me to solve this problem without taking it to a shop.also my o2 sensor on the cat is diconnected,because my exhaust is broken at the flex joint.

 

Welcome to DF
The o2 sensor could cause the engine to run rough. On the speedo, 3.3 engines didn't come with a 3speed transmission. I think you mean a 4 speed? I would check the wires at the output sensor connector. A wire maybe broken inside the connector.

 

I had a similar issue a month ago. the engine ran really rough. Died after a few seconds of driving. Would start right back up but did the same thing. It felt like the engine was almost jumping out of the hood. I took the plenum off to clean the carbon off, and thats when I noticed that the fuel injection harness had a wire showing. I took the tape off the harness and it was melted together. I had 8 codes at that point. Bought a used harness from the junkyard for $100.00. Replaced and all is well. The harness is located right over the exhaust. If you can take a look at it. This might be your problem. Hope this helps.