Ok so my girlfriends 2010 grand caravan with 3.8l started having issues, the check engine light came on as well as the ETC, ESP light so we had it scanned. The result were the P0507 code, P2173 code, C121C code. Since then I replaced the front right wheel beading as it was bad, but the vans issues got worse, now it occasionally smokes like a chimney, smells sort of like burning oil but with a hint of hot elecrdonics smell.

The van starts fine, when driving the cruise doesn't work, the transmission doesn't downshift into passing gear and it surges going down the road. I replaced the sensor on the top of the intake, going to,pull the electric throttle body off my stranger that has the 3.8l and see what that does. As far as the smoking can anyone help me there? It has me truly stumped.