You have at least two problems:

61psi is the maximum pressure that your pump can produce, and that's too low, needs to be 70psi to 100psi. Needs a new pump. When you tested at the service port, the 61psi is what the pump is producing, so at this point, we don't know what regulated pressure actually is because it is indicating maximum pump output pressure. Your regulated pressure might be higher, but not lower than 61psi. Basically the regulator is not opening to regulate the pressure. Regulated pressure must be 55psi to 61psi.

The leakdown to zero at the service port is a problem inside the plenum. Could be a leaky pressure or return line, leaky injector, leaky spider line, leaky poppet valve, internal or external regulator leak.

 

Well I have all the stuff to replace everything in the plenium.im also replacing the intake manifold gasket while im that far into it

Rick

 

Next question, when it fires its running very rich..I can smell it it of the exhaust.sometimes its almost like thee is raw fuel coming out of the exhaust..if the regulator isn't opening how is this thing even starting.

Rick

 

The pump pressurizes the fuel line from the pump, the service port, the injector, the spider lines up to the poppet valves, and up to the valve plate in the regulator. The green line indicates fuel flow. The arrow on the left comes from the injector. The arrow at the top goes back to the tank through the fuel return line.



The spring in the regulator keeps the valve plate closed allowing fuel pressure to build. When fuel pressure overcomes the spring pressure, the valve opens. This causes the pressure to drop, and the valve closes. This is how the regulator keeps pressure constant. If the pump can't build enough pressure to overcome the spring pressure, all you get is what the pump can produce. The regulator keeps pressure from getting too high, if pressure is insufficient, the valve plate stays closed.

Edit: The injector assembly comes with a new regulator. You'll also need this part: http://www.dormanproducts.com/itemde...1&SEName=55163 It connects the pressure line to the injector and the regulator to the return line.

 

Thanks so much for your advise everyone..it is much appericiated
Rick

 

I got my fuel delivery problems fixed. I replaced the pump, the CPI unit, the hoses going from regulator to the fuel lines. When I opened the plenum up I could see where the fuel had washed and there was still fuel inside. Being I knew I had a rich running condition I also replaced the O2 sensor. New plenum gasket. Fuel pressure at the pump is 91 psi and holds for 10 minutes. Snap throttle test at plenum is 62 psi. Key on engine off pressure is 55 psi and holds for over 10 minutes. The truck runs much better but still has rough idle on start up and smokes out the exhaust. 2 minutes after startup smoke goes away. Should I be looking at ignition system next. Also the people before me cut the cat out of the vehicle..could this cause problems. I know it will cause the check engine light to come on..
Thanks for your help..

Rick

 

What color smoke? White, blue, or black? There might be a problem with the ECT, (Engine Coolant Temperature) sensor. When the engine is first started, it operates in open loop and the ECM ignores data from the oxygen sensors. It uses data from the other sensors to determine the proper fuel mixture. If the ECT sensor is not reporting correctly, it can cause the fuel mixture to be incorrect. When the oxygen sensors warm up, the ECM switches to closed loop operation and uses oxygen sensor data for determining fuel mixture, which is far more accurate. It will require a scan tool that can view live streaming data to determine if the ECT sensor is accurate. When the engine is stone cold, before you start it, compare ECT and ambient temperature, should be within a couple of degrees of each other.

 

That sounds sensible..I forgot to say I replaced the ect but that doesn't mean I didn't get a bad one.. I also replaced the sensor that goes to the gauge..I just went and started the truck and noticed the temp gauge went up to almost the red line.. then went down to 210. The smoke is white
Thanks Captain

Rick

Rick.

 

You could replace sensors all day long, but if the wiring has a problem, you'd never know it. That's where a scan tool comes in handy, it will tell you what the ECM is seeing for an input.

White smoke for a couple of minutes is normal when ambient temperature is ~40F or less. It takes a bit for the condensation in the exhaust system to vaporize.

 

I will try and get my hands on a scan tool...if not I will pay to have it scanned..this truck runs really good now once it gets up to operating temp again thanks for your help.

Rick