Pinkston

I have a 01 3500 with a edge programer, mach 4 ingectors, and hx40/ht3b twins. The truck has been set up this way for about 4 years. I daily drive the truck and am pretty easy on it.

Recently I have noticed some surging and have narrowed it down to anytime the truck builds over 20 psi of boost. What would cause something like that? Are the turbos not working well together?

DIESELWRKS

can you explain more when you say surging? do you see anything on your fuel pressure reading when this happens? do you feel the surge anywhere?
is it breaking up? like on off on off with the power? your fuel filter is it old?
codes? I would look at all electrical connections , batteries, grounds pos/neg.
your connections with your aftermarket tuners. check your connection to the pump tap.

does this surge go away above 20psi. have you noticed your boost is slower to build? are you getting the surge at approx the same RPM? engine cold? warm?

P0122 Throttle Position Sensor/Switch A Circuit Low Input . this code will cause surge.

if you haven't checked for codes, Check them. assuming you know how to pull them using your ignition key (cycle trick).

Pinkston

Breaking up like a on off switch is a good way to describe the surging. I only let my truck see 20 psi of boost once it warms up so I cant say if it does it cold. I feel the surging in the whole truck. I can build more than 20 psi and it still surges, just does not seem as bad as right at 20 psi.

I put a new airdog 150 on 2 months ago and have changed the filter once since then. I am not too happy with the airdog, even with their stiffer spring my fuel pressure reads between 10 and 13 when running. My old FASS sat at 13 no matter what.

I can tell that RPM makes a difference. I was towing this past weekend so I saw 20 pounds of boost more often and it would surge at all rpms. The only codes I have are P0230 and P1693. The 230 is because of how my fuel pump is hooked up, the plug in my harness is damaged so the fuel pump relay is triggered by another fuse when my key is on.

I will look over all of my connections and see if anything is loose.

Pinkston

Playing around with it a little today I found that it does not seem to surge when the edge is turned down to 0. Guess I need to check all the connections on it. What changes in the fueling on a edge above 20 psi of boost?

Lary Ellis (Top)

A very common issue with the Edge programmers causing surging when they go bad, seen it many many times on the old 24 valves.

DIESELWRKS

I personally think your 10-13psi fuel reading is really low. is that normal for an airdog replacement. my FASS/150 is 19-20psi cruising. low fuel psi with a timing box like your edge can create a lack of fuel or to low and that can cause surging.

10-13 is assuming at idle and cruise. what is the reading of your fuel pressure when the 20psi/boost surging happens.

your signature also says you have a quad/adren.. do you have both of these timing/boxes at the same time??? or just the edge now