Another cause may be your programmer or module if you have one. "We see this code sometimes because of the programming,"_ Layton said. "To add the power that a programmer does, there are certain lies we have to tell the computer in order to get the power we want. This sometimes causes the P2290 code to pop up."_
One of the most popular modifications people perform is to block off the exhaust gasses from the intake. Whether it is unplugging the EGR valve or blocking off the up-pipe, the exhaust gasses are not flowing into the intake. The computer expects to see a reduction in air flow through the intake when it calls for the EGR valve to open. So with that not happening, codes P0401 and P0402 can be triggered.
- P0401: EGR Exhaust gas recirculation flow insufficient: detected EGR valve, sensor failure.
- P0402: EGR Exhaust gas recirculation flow excessive: detected EGR valve, sensor failure.