Engine acted like I shutoff the key and immediately turned on the key
 

The other day, truck started up ok....while idleing letting it warm-up for about a minute.....the engine acted like I shutoff the key and IMMEDIATELY turned on the key. Like a realllly big misfire/stumble. Then driving to work, 14 mile trip on the freeway, it did it again. Since then it has a ever (realllly slight) roughness at idle. Runs good at cruise. Both times the engine didn't die.

My PSD did this, and when it went to heck, it was the CPS, but the 7.3's were known for bad CPS sensors.

I've had 3 injectors replaced, a lift-pump, and a Pressure Limiting valve replaced so far.....

big red psd cc,

Do you happen to have an aftermarket Security System/Remote Start/Turbo Timer, on your truck? If you do, I may have your answer.

Big Bob

Big red, I was going to say it sounds like your CPS but I see that you already have that one figured out.:D And having had a PSD you already know all about that thing. [laugh]

No alarm system or turbo timer.

I get similar behavior occasionally, but it's noticeable only when towing my 10k lb fiver and only at low rpm (nearly idle) while parking or maneuvering. That is, I've never noticed it happening while under power. It is very much as you describe: the engine all but stops running for a second or two, but somehow keeps running.

Neil

Thats just about when it does it.

Re: Engine acted like I shutoff the key and immediately turned on the key
 

Sounds like your truck is recognizing the mods.
Check your line and connections from the lift pump to tank. Might be sucking some air. A vac gauge would confirm. Did you change fuel filter?
You should be able to see code for cps. But your banks may be fooling it( ???).
How did they diagnose the pressure limiting valve? How was it acting before they replaced it?

They replaced the pressure limiting valve 13000 miles ago.

I changed the fuel filter two days ago, it was nasty. 9,000 miles on the filter since the last one.

I am not going to worry to much about it, because the truck runs great, just that it did it once here and there.

That's more or less the conclusion I came to. FWIW, I haven't noticed it since I had the mileage flash done.

Where are you in Simi, East or West side? I'm on the S/W side.

Neil

Yosemite and the 118....

Has it thrown any codes?