Hi folks. I posted an introduction so I'll cut to the chase. 2002 civic Ex tripping 3 codes. P1259, P0401, and P1457. I just got this car and I do have the maintenance records. Last time the PO took it to the shop the dealer replaced the VTEC solenoid and cleaned the EGR ports. Light came back on and I do not know how long after the service. So can you offer some advice on were I should start. I'm a field service engineer on gas turbines so I do know my way around a tool box

 

Cleared the codes and the P0401 came back first so EGR valves it is. Searched for any vacume leaks but didn't come up with any. Anything I should look at first before I change the valve?

 

EGR valve is new so I removed the intake manifold and the passages were solid with carbon. Car had been at the dealer not long ago and they billed the PO for cleaning the passages. The must have just sprayed some carb cleaner down the EGR hole and called it good. No way that light was going to stay off. So that issue is solved for now. I'm getting a surge during light acceleration, which was there before I R&Red the intake. I'm thinking air leak in the induction system so I'll look into that. Anyone have any other ideas?

 

Found a loose connection on the throttle body to air cleaned box joint. Secured that. Car has tripped the Aft O2 overvoltage code. The connection to the sensor was loose and dirty so I corrected that and cleared the code. I'll drive it for a while and see if it comes back. If so we will R&R the sensor.

 

Ok some progress. The 02 code has not come back. The car hesitates during acceleration. It's worse during a accel in 3rd. I changed the plugs which were pretty worn and it dose have more power but the hesitation is still there. Looking for any suggestions.