Read codes; get the following: Two different sets; first set is the
first time; then a reset; second set is what it set the next time.

P1247; P1248; P0236

P0236; P0237; P1248

I had t'd into the MAP line with a boost gauge; didn't read boost at
WOT; but it will build 10psi at part throttle and seems to have a
smooth/linear build rate that is appropriate.

The truck runs fine, shifts fine, you really wouldn't know there was
anything wrong except the light comes on.

The MAP line is clean/unobstructed; no leaks. MAP was replaced
approx. 1k miles ago;(apparently in error). The hose fitting at the manifold is
clear/unobstructed. All boost tubes/connections are tight. The
red/green molded plastic lines that run between the intake
manifold/air inlet/etc; all those hoses are clear/clean unobstructed.

Any suggestions as to what to look for? Seems electrical, not
mechanical at this point.

On code P0236; I have a description of "Turbo boost press Circuit A
circuit performance". What is "circuit A"?

The only other thing is that it takes "X" number of key cycles for it
to set the light. It ONLY sets the light immediately after the gauge
cluster bulb test sequence. It never sets the light running down the
road; only after the key position goes to "run"; bulb test; then the
light stays on and the codes are set.

Any suggestions would be greatly appreciated. I need something beyond the usual "check the lines and hoses". I've searched the code sets; apparently this is not uncommon for the 7.3 to have on occasion; but I've yet to find any resolution to it.

 

40k on your truck!!??!?!?! I am green with envy! I've got 183K.

If your truck seems to run fine, it could be an intermittent electrical fault. Check around moving parts (hood hinge, all of your pedals under the dash) to make sure you aren't chafing any wires. Also, I would disconnect, clean and reseat connectors that are in the lines to make sure that you don't have a spotty connection in there. I'm sure there's a connector under the hood for the boost signal that could be cleaned. I have an intermittent one for the IDM, but no change in performance when the SES is set. When I have the time I'm going to do the same thing and hopefully it will go away.

At the very least it's only an investment of time instead of money to see if that clears your issue. It seems unlikely for a part failure if there is no change when the light is set.

Just my .02

 

Yeah this is my Dad's Excursion; really hasn't done much, never towed and really never given us any trouble at all of any kind until this.

I hit the MAP/Baro sensor connection with some contact cleaner, no change thus far.

Thanks!