I just had a Dipricol fuel pressure gauge installed. It has acted funny since the instal. If you start the truck,<br>and let it idle, it will go to 15psi. If you start the engine and leave immediately it goes to zero then up to 5 then all over the place. At acceleration it either goes up or down. <br>This is a cold start. When the truck has run for a while, then been shut down it goes to 15. Of course when you run down the road it sits<br>at 10 or 11. The other day however I had drove about 100 miles then shut it down for approx. 30 minutes. When I started it up it went to 5<br>then down to zero. It stayed at zero until I stopped for a light and it idled for a bit. Then it went to normal pressure. What is up? I had the lift pump <br>checked. It was fine. Could the gauge be bad, or an air bubble be causing some funny readings? :'(

 

I have a ISSPRO Mechanical and mine does the same, kinda, sorta thing yours is doing. The consensus opinion seems to be the cold weather, warmup time and since we're newly installed, we may be working out some air bubbles. I'll keep an eye on it but I'm not too concerned right now. After you're warmed up and things seem stable, what you getting for WOT? 10-11? Hey, that's lookin' good from what I understand. I'm getting 10-11 so I'm pleased with that. According to Push Rod, these symptoms are not all that uncommon.<br><br>~Dave

 

[quote author=Hired Gun link=board=4;threadid=9258;start=0#88856 date=1041859545]<br>The other day however I had drove about 100 miles then shut it down for approx. 30 minutes. When I started it up it went to 5 then down to zero. It stayed at zero until I stopped for a light and it idled for a bit.[/quote]<br><br>At startup, its normal to see lower pressures by a couple PSI, until things are warmed up. However you shouldn't be seeing 0 or 5 PSI while the truck is running, no matter how cold it is. If you've got an isolator, it sounds to me like when cold, the isolator is binding and not giving you proper readings. I'd give it a couple weeks, and see if things loosen up. If they don't, contact your supplier.<br><br>NWDave - If you're seeing the exact same thing happening (0 or 5 PSI while the truck is running for more than a few seconds) let me know. Thats a faulty gauge.<br><br>Rod

 

Thanks. At WOT on the above post I am seeing 6 and 7. At over the road like 60 through 70 mph I see 10 and 11.<br>Thats with the TST PM 3. I havent installed the injectors yet. I need to get a pusher pump. I think that will help and extend the life of the lift pump.