I have a 98 grand caravan with the 3.3 flex engine. Recently while trying to change the water pump I had 2 of the bolts break off flush. Had it towed to a shop, they attemped to extract the broken bolts, even removed motor mount and slightly lowered the motor to try and get a better angle. Couldn't get it. They had to remove the timing chain cover to get full access for repair. Picked up van and next day noticed a vibration / rattle--from engine all the way through the exhaust line (maybe). Any help on what they could have done to cause this, or what could be causing this. It happens only between 1200 and 1400 (approx.) rpms. And a lot more noticeable when moving than in park. Van has 160,000 miles on it. I plan on taking it back to them on Thursday, but wanted to be armed with a little information, before they try to tell me something off the wall.

 

Welcome to DF
It maybe a motor mount. If it wasn't before, its a good chance it was something the shop did or didn't do.

 

Thank you sir, that is one of my thoughts. Could it have anything to do with the crankshaft damper??

 

It could, But i would ck to see if the exhaust is the sub frame or a bad CV joint.

 

Took it to the shop today, mechanic says he found the bottom bolt on the alternator bracket loose....admitted most likely his negligence, running okay now.