94 Dodge B250 conv van

[R_Lalau]

I recently brought a used conv van, the only problem was the catalytic converter. The van ran fine except for the noise the converter was making. I ordered the converter and a maintenance guy installed it, but he messed up the muffler too, so I ordered the tail pipe and muffler. He installed it.

Now heavy black smoke comes out the tail pipe, which i thought it was ok since the converter was not working properly and now all that gump is coming out.

But when driving at 40 mph or up to 70 mph, the van starts to jerk when I attempt to decelerate (when I take my foot off the gas pedal) . I have to pressed the gas pedal again for the jerking motion to stop. It also happens when I slow down at a stop light, it would jerk again.

Friends of mine said that the maintenance guy did something to van beside working on the exhaust system, is that true?

Could the van be sort of like in shock now that it can breath again due to the replacement of the exhaust system (tail pipe, muffler and converter)? Is there something else I was suppose to do when replacing the whole exhaust system?

Could you help determine what causing the black smoke and the jerking motion?

Thanks in advance...

[bejay]

black smoke is an indiction of the engine getting to much fuel suggest taking to shop to determine what is causing the vehicle to run rich if you continue to drive the vehicle while it is running rich you could ruin the convertor you just had replaced.
there is really no way of knowing if the person you had working on the exhuast system did anything else to the van.
the jerking could be related to the rich condition or could be driveline or transmission related suggest you inform the shop of that problem also when you take the vehicle in to be looked at.