Sorry keep missing this ...need to check fuel pressure regulator ..if not it ..fuel pump time.
Pressure same on 4.8 . here is a link ..and a pic of location of regulator. If you smell fuel..or see ..regulator bad. click on red link
1500 series: 2000 silverado..4.8 V-8 engine..starts fine..hard start - JustAnswer
Gm had two diff types of fuel delivery ..if you do not see the regulator ..it will be under the plenum that covers system will not have a vacuum hose to it.
Sealed system reg. get vac this way. Will be on the end of the spyder injector .. if you have this be best to upgrade to newer system .Pretty sure 4.8....5.3..6.0 had the rail system ..5...5.7 had spyder in 00
Should be about 60 psi on the fuel pressure but need to check on the 4.8 dunno if its the same but should be.
Originally Posted by dirtrider73068
sorry didnt pay attention to the year...not a tb....use silicone spray intseat of starter fluid
Originally Posted by leolkfrm
We installed a new fuel pump an now gets up to and holds 60 psi at the test valve still does not want to continue to run although its running longer then it has before
You had tps codes would check or replace it.
- Malfunction Indicator Lamp (MIL) illumination (Check Engine Light or Service Engine Soon light)
- Intermittent stumble on accelerationhttp://images.intellitxt.com/ast/adTypes/icon1.png or deceleration
- Blows black smoke on acceleration
- No start.........What it does: The TPS provides the computer with information of the position of the throttle blades. The sensor is a 3-wire design. A 5-volt reference, a ground and a computer signal are contained in the system. The TPS acts as a potentiometer to send the computer the resisted signal. The sensor is mounted to the Throttle body and usually attaches to the throttle blades via an arm, which rotates the center of the sensor.
The voltage sent to the computer will give the system the information needed top allow for correct operation. TPS voltage is used for establishing "clear flood mode", engine load and throttle angle for use of the computer systems as well and transmition operation
A faulty TPS could result in a no start, start and stall, erratic performance or transmition shifting problem depending on the type of faulty. Generally a faulty TPS will see the following codes:
21 Throttle Position (TP) sensor circuit (signal voltage high)
22 Throttle Position (TP) sensor circuit (signal voltage low)
P0121 Throttle Position (TP) sensor circuit insufficient signal activity
P0122 Throttle Position (TP) sensor circuit low voltage
P0123 Throttle Position (TP) sensor circuit high voltage
A faulty TPS will not always set a code. Sometimes a glitch in the sensor will allow it to function correctly except for at certain spots in the resistance bored. In this case it will usually not cause a code to set. For this reason a "sweep test" is best for finding a faulty TPS sensor.
Most GM TPS sensors use this system of wiring.
Grey: shared 5 volt reference from the computer
Black: shared sensor ground from the computer
Dark blue: input signal to the computer.
Testing and diagnostics
In order to test the TPS you will need: a multimeter for circuit testing and a multimeter or scanner for sweep testing.
Turn the key to the on position. With your multimeter on volts scale probe the black wire. Do you have full system ground?
If yes . next step
If no, check condition of black wire back to PCM and repair as needed
Next test for 5 volts at the grey wire. Do you have full 5 volts?
if yes continue to sweep test.
if no, check condition of wire back to PCM and repair as needed
Probe the dark blue signal wire with your multimeter with the key on. you should see anywhere between 0.20V and 0.80V . that is an acceptable range however 0.60-0.80 is considered the best range.
if you are not in that range then you have to do 1 of 2 things.
if your TPS is adjustable (bolt holes slotted for movement) then you need to adjust the reading to above before continuing the test.
If you have a non adjustable (auto zeroing) TPS then you are in need of a new sensor.
Sweep test: Now you need to probe the signal wire with the key on while very very slowly opening the throttle. AS you give more throttle the voltage will start to increase. You need to watch carefully for a smooth, glitch free raise in voltage. If at anytime the voltage make a large jump, a large dip, drops to zero or jumps to above 4 volts the sensor is bad. Continue the sweep test until you have reached wide-open throttle at which time the voltage should read over 4 volts.
Look and read this on your p1637 ww2.justanswer.com/uploads/mcvgreg/2008-12-26_204058_2000-Silverado-P1637-Chart.pdf
But after you truck is running clear code see if it comes back. I would check or change the tps..located on side offthrottle body.