so awhile back I posted about check engine issues got a new flex pipe welded in and thats when i got the light. Codes are all 4 o2 heat sensor codes egr valve elertrical malfunction and fuel evap elertrical malfunction. Put new egr valve selonid new rear o2 sensors new egr and still nothing. Was talking to an audi mechanic and said he ran into this once befoe he said it was a fuse or ground wire that all the emission stuffs on,but it was so long ago he dont remember where this is.So if anybody has info or wiring harness diagram i would appreciate help.

 

theres a ground on the firewall near the or connections behind the coolant tank, easy to spot, brown wires diferent pole than all the other firewall posts. Theres one on the back of the throttle body, theres one on the pass side frame rail right at the engine mount. Ive taken the whole harness out and thats all I remember.

 

thanks ill try that out later on today and see how it goes

 

cleaned one behind coolant res and the one on throttle body and replaced the lower ground and still nothing

 

anybody have any thoughts

 

anyone out there?