EGR/DPFE/ Problems in general.
Ok so in the last week or two I've been diagnosing my car's SES light that has been on forever and a half. I do have an Off-Road H-pipe and yes this is when the car's light has gone on, however the code was the typical 400001 indicating that there is insufficient flow to the engine from the EGR system. After doing my research it seemed that the sensor was the primary culprit, but I replaced the sensor and two days later the SES light reappeared. I decided to swap the EGR valve out and again 2 days later and the light appeared. I understand that it may be due to carbon build up in the pipe connecting my header to the EGR valve, however I have no idea how to reach the bottom nut as it is in a ridiculous position on the passenger size. I also know that this nut must be greater than a inch because I could only fit my adjustable wrench around it as my largest open-end wrench is a 1". Other than cleaning out the pipe what could this problem be due to? The car isn't suffering gas mileage or stalling etc, but it's really pissing me off. Also how in the hell do I reach the lower nut connecting the EGR pipe to the header? I raised the car up on jack stands and it looks to be more difficult to reach from the bottom of the car than from the top. I know this subject is beat up a lot and i tried to do my research first and resolve it, but now I turn to you guys for advice.
2002 True Blue V6 to GT Vert
16.1@86 as an auto 3.8
2.15 60', 9.3@77, 14.4@96 as a 5spd SOHC 4.6