I was driving the other day and all of a sudden my CEL came on and i look at my speedometer and see that it is at 0 even though i was going like 60 or so. IVe known that my speed sensor is messed up but i never had the chance to replace it, so what usually happened was that my speedometer would start going crazy when i drive, but no CEL. So then on sunday i was going to work and i hit WOT in 3rd and at about 5k rpms i get fuel cut. When i stop at a light i noticed my idle was lower than usual, at about 300-400rpms.

I got the code read today and came up with:
P0500 Speed Sensor malfunction
P1507 Veh Idle air Control valve malfunction fail safe

I know i got fuel cut and stutterring because of the failsafe feature

These 2 codes have come up together in the past, but i cleared them and never got them again until this weekend.

I am going to replace my speed sensor tomorrow, and i hope that is the cause for both issues.

Does anyone know if these two problems can be related to each other or why they are? Did my idle drop because of the fail safe?

Thanks for any info.