help pls

[vs,n/a,v6maxi]

vs v6,have pro cleaned injectors & throttle body, changed both oxy sens, had chip checked, changed plugs, leads, coil o k,diagnostic pro tested, cant find problem,,,,,car go's hard but on idle runs rough,, blows & spits black smoke,tail pipe black, nearly stalls, fuel eccon good since all above work done.. plenty of work done to motor and box 18 mths ago no probs till about 6-8 weeks ago,could earth wire b prob???????????? help pls

[jas98]

check/clean the IAC valve on the throttle body and/or clean the throttle body...otherwise not to sure but im sure someone else on here may have some ideas

also give teh car a error code check

[moff_man]

and check for vaccume leaks around the throttle body and intake pipes....

[vs,n/a,v6maxi]

sorry checked iac valve ok, no vac leaks, no manifold leaks, thanks 4 replys,have read that chassis & body earth could fix prob,anyone heard about this///

[slipstream001]

maybe get it compression tested, and also get your timing checked if its out could cause it to idle rough. not too sure about the electrical causing a rough idle. just a thought as my mates GTS developed a "lame" cylinder and it had somewhat the same symptoms could also be your injectors sometimes its something so small yet we think its something major lol, maybe some wynns spitfire to clean your injectors