Sorry not sure if I am putting this in the correct place.
New at posting so bare with me. I did the Check regulated fuel pressure, pump max output, & leakdown per Captain hook thread. I found my fuel pump to be bad, It would drop to 0 at the test port and at the filter. I replaced it and the filter, tried it and found a leak on the fuel hose coming out of the pump. Replaced the clip and leak is fixed. Tried to start and it sputtered a little and finally started but ran a little rough but it was before this also. Re started 3 or 4 times added the rest of my fuel and was going to take it for a ride and it would not start. Checked fuel pressure at filter and it pegged my gauge(over 100)turned it off for 10 minutes and held at 95. checked at the test port and it hit 61 then drops to 55 but doesn't hold there it drops to about 50 after 10 minutes. So I took off the plenum and it's all nice and clean(not good). So I hooked the fuel lines back up and ran the pump manually in fuse box and didn't see any leaks. I pulled out the popits and none are leaking. Do I need to fire the solenoids or whatever they are to see if I have leaks? I did replace the pressure regulator to try something and it still drops to 50psi. 2002 4dr 2wd. Thanks. I do have spark.

 

Any help would be appreciated. I am trying to find out why my intake plenum is all clean when it shouldn't be and need to know if I have to somehow fire the spider to see where it's leaking? Thanks!

 

Do I need to plug the spider back in and disconnect the coil and crank it to check for leaks?

 

If the spider was leaking maybe it needs to be in the installed position to leak. Are you sure that it is not also dropping that last 5 pounds at the fuel filter as well? If you want to fire the injectors:


George

 

The test at the fuel filter went over 100psi and held at 95. I have the plenum off right now so I was trying to find the leak.Is it possible the pressure regulator was leaking under vacuum and not leaking just under pressure? Can I plug the spider back in and crank it with the coil disconnected to check for leaks? Thanks for the reply.

 

Try this:

https://troubleshootmyvehicle.com/gm...uel-injector-1

George

 

So I thought I would just put it back together and try it. Still no start. I did notice the check engine light on when cranking it over. So I checked for codes. P0118 and P0122. Would the P0122 cause a no start? Is it there just because I had it unplugged? I didn't turn it on when it was unplugged. I will check the connections tomorrow to make sure it's plugged in. Not sure why the 118 is there. Will check that also.

 

What year is your truck? Those codes are ECT sensor and TPS. Sounds like you have a connector or wiring problem in the area that you are working. Open, short, loose connector, etc

If not then its probably faulty sensors, PCM failure, ground problem or you may have lost your 5V reference

George

 

Same as yours 2002 LS 195,000.

 

Are you wanting to fire the injectors to look for leaks in the spider/plenum or are you wanting to know if the injectors leak down into the cylinders after they are fired?

i don’t know how likely it is that a regulator can leak under a vacuum and not leak at atmospheric pressure but didn’t you replace the regulator? If so and the pressure behavior is exactly the same then it would seem that two regulators having the exact same behavior would be a low probability.

George