p1409 p1401 and p0457...EGR delete with diablo tuner
 

So I recently deleted my EGR. I removed the solenoid and the DPFFE sensor and plugged absolutley all vaccum lines and capped off the EGR tube with a 22mm female cap. On the diablosport i turned off the "EGR valve" but i am still throwing these codes along with the "check fuel cap" light (P0457). cleared the codes and they keep coming back. is there a resistor i can use on these sensors and what can i do about this gas cap light? does that have to do with EGR?

It sounds as though the Diablo tuner did not properly turn off the EGR in the tune. There is a single scalar value, EGR Selector Switch, that needs to be set to 2 (from 1) to disable the EGR. If this was not done (I have seen some systems that set this to 0 when attempting to disable the EGR) the monitoring routines will continue to check the EGR components.

The P0457 code is unrelated to the EGR system and is only triggered by either a fuel tank pressure change of less than 0.25 psi has occurred within 30 seconds after refueling, or the EVAP purge is seeing a vapour flow of more than 0.06 pounds of vapor per minute.

In addition to the fuel cap being bad this may be caused by a leaking filler tube or gasket. If you have not yet done so pull the corrugated plastic sleeve from the filler tube (circled in red below) and see what it looks like--it is not uncommon for them to rust out in the Northern climes...

http://www.paladinmicro.com/images/F...erDrain-02.jpg

Ignore the seemingly disconnected hose being held by the fellow that took this photo, it is the overflow drain for the filler cavity and is supposed to be routed out through a hole in the lower fender:

http://www.paladinmicro.com/images/F...erDrain-01.jpg

Here is what is often found after removing the plastic sleeve:

http://www.paladinmicro.com/images/F...lerRust-01.jpg

Thanks for the help Cliff! I removed the sleeve and found the tube had very very little corrosion, so it cant be that. I cleared the code and it hasnt came back in between a 10~ mile drive so I'll see what happens. Hopefully its gas cap. Im going to re-tune the EGR and see if it helps. Is it safe to run resistors on those wires? Being hot in the engine bay and having the resistor hot itself may cause problems?

It would be possible to place a 33 Ω, 10 W resistor across the EGR vacuum regulator solenoid (P1409) wires, however it would be dissipating 7 W or so and get rather hot. The other issue, P1401, would require a regulated voltage source to feed 3.5 V or so to the PCM. Neither of these is a particularly viable solution when just properly turning off the EGR system in the tune would take care of the whole issur.

I hooked up the DS tuner and went and turned off the EGR Switch again. Re-installed tune and the codes are still showing. And when I go to "Trouble Codes, "Read Trouble Codes", it says "No trouble codes found". I hit "Clear trouble codes" and nothing is cleared...?

If I hit "Clear trouble codes" first, then go to "Show trouble codes", it will go to an option that says "OBII system readiness..." and if I select that option it says "P1000, OBII system readiness test not performed" or something along those lines.