code possible problem?

[maverick_935]

I had my codes read and found these:
p0401 Is this caused by my modifications?
p0404
p0676 is there an issue with glow plug wiring on 6 & 8?
p0678
p0700 replaced tranny neutral switch!
p0735

Thanks

[More Power]

P0401- EGR Flow Insufficient
P0404- EGR Open Position Performance
P0676- Glow Plug #6
P0678- Glow Plug #8
P0700- TCM is requesting MIL illumination
P0735- Cannot shift to 5th

The EGR codes could be due to any programming or aftermarket modifications. The aftermarket vendor would be the best source of info for any conflict that might exist.

The glow system codes are not likely related to the EGR system codes. Check out the glow plugs and their individual circuits.

The NSBU (Neutral Safety Back-Up) switch replacement could help with the P07xx codes.

Jim

[Kennedy]

The EGR would be due to teh 4" exhaust with no cat.

The glow plugs could just be bad.

Teh P0735 is a 5th gear slip code caused by the power adder. There is just something about the "harness box" type mods that tends to slip teh Allison. I believe it is teh delayed "kick in" of power followed by a rush of added fuel that gets them. With ECM programming we can actually make the truck run stronger, cleaner, cooler, and more responsive (smooth, relatively flat TQ curve) while not limping the trans if you can believe that.

[maverick_935]

# 6 and 8 glow plugs replaces because they were not working and installed blocker plate and finger stick for the egr codes.

so far everyting is working well.

Thanks.