HPOP Surge

[rayrayray01]

I've got a late 99 7.3L F350 Dually with 327,000 miles. I'm trying to diagnose a strange issue that I really need help on. The injectors are the original factory injectors that came in the truck.

All the items listed below are new:

stock turbo
turbo pedestal with EBPV
glow plugs
glow plug relay
air heater relay
fuel bowl heating element
valve covers
valve cover wiring harness
cam position sensor(CPS)
fuel filter
oil filter
fuel pump
fuel sending unit

The truck also has the aftermarket add-ons:

Strictly Diesel regulated return (set at 65 psi)
Strictly Diesel high pressure crossover(HPX)
HPOP gauge (isspro)
turbo gauge (isspro)
fuel pressure gauge (isspro)
modified and rebuild transmission

Alright this is what's going on I'm going to explain this as if they are three separate issue but as far as I know it could all be due to the same thing and actually be just one issue causing multiple symptoms.

1. This is only on the first start the rest of the day she runs like a top. I can get in the truck on a warm day or cold day (40-90 degrees) and cold start it without letting the glow plugs warm up. The engine will kick right off. The engine lopes or acts like iis not firing on all injectors but its more like a lope to be honest. Give her about 15-30 sec and she will smooth out and idle just fine. Now if I let the glow plugs warm up before I start her; she will start just fine with no loping.


2. This is in correlation to the first one. This only happens when I first get in the truck. It doesn't do this if the truck has warmed up to full operating temperature. Start the truck, start driving and the truck is missing power. If I baby it at low RPM in 2nd and 3rd the truck will do a shake and shimmy kind of thing; it feels like it is coming from the engine. It doesn't do it in 1st I've never tried babying it up into 4th to see if it does it either. However if I stomp on it, it will crawl along and once the RPM get somewhere around 2500 in 1st it acts like something either gets thrown open (I'm thinking exhaust back pressure valve, EBPV, but I haven't tied the thing open yet) or a shot of nitro is dumped into it, your head is thrown back in the seat and you're up and gone. From that point on it runs fine for the rest of the day.

Both of the ones above I'm accounting to either a stuck EBPV or really old injectors. The one below is the main on that I'm curious about.

3. I can stomp on the truck and it will hold 2700-2900 psi up through the gears on the HPOP gauge, not bad for a 200,000 mile HPOP. I'm going to have the IPR check in a couple of days to see what its saying. With the cruse on running at highway steep 60-75 mph heading up hill were the HPOP has to work just a little harder to keep from dropping speed the HPOP will surge. At my main driving speed 75 mph my HPOP gauge will read 2000 psi. Crawl up a hill it might go to 22-2400 psi but there are times it will surge between 22-2900 psi. You can hear the surging in the engine and feel it, so that knocks out a gauge problem.

I'm looking for any thoughts and opinions on possible resolutions to the problems above.

Thank you for everything, Ray

[rayrayray01]

Well I figured out what was causing my issue. Took the truck in today and got the shop to hook it up to the scan tool and the IPR was reading 7% at idle and 40% at full throttle. The HPOP didn't loose any pressure through the entire test run according the scan tool nor did the IPR reading change surge any. I drove and the teck read off the scan tool. So he started looking at the ICP reading every time my HPOP gauge would start surging the ICP voltage would jump all over the place. It didn't do it at full throttle or being easy on the throttle but at 50-75% roughly it would surge every where.

So I've got to get a new ICP.

[rayrayray01]

Well I got the new ICP installed Monday and it seems to have fixed every single problem that I described up above. For the past two days the truck has hit off with no warm ups nor was it missing any power when I first started it. But we are also in 100+ degree temps now so that could have a lot to play in it. I'll continue to keep updates going.