Repost: power loss issue

[topp]

Did you clean out the bottom of the tank when you replaced the pump?
Have you blown out the fuel lines?

[Irish_Alley]

almost sounds like your old filter was dirty and when you changed it it allowed more dirt and grime to clog the new one

[Irish_Alley]

also get a fuel pressure tester and see what it says

[big bear]

yup, id surely check that filter again.

[nativetexan]

I replaced filters three times, thinking that it was the fix, until I shut the truck off. I put a pressure guage on it, when I rev'd it up and it did what it does, the pressure went down almost close to zero. When I took the filter out I blew out the line going to the engin and the tank from the filter location. I don't know if three filters could have been clogged up. And yes, I cleaned out the tank when I took it down. There wasn't really any junk in there, but did it anyway...

[big bear]

i had a fuel problem with my truck few years back, before the motor swap. and  i thought i had tank cleaned out, i went through 5 fuel filters.

[Irish_Alley]

crank the engine with the fuel line unhooked and have it in a glass jar see what you pick up

[nativetexan]

http://www.youtube.com/watch?v=IREmS_b1k5s


Here is a video of what the truck is doing.

[nativetexan]

crank the engine with the fuel line unhooked and have it in a glass jar see what you pick up

Uh huh? How do I crank the engine with the fuel line out? I unhooked the filter and turned the ignition to activate the pump and it pumped. It has the right PSI until I put a demand on it via the gas pedal...

[Irish_Alley]

lmao i forgot about the tbi thought it was a carb but key the ignition and see what happens. what’s it look like? any grud

[nativetexan]

I did it a while back, didnt see any crud in it.. nice and clean..

[jaredts]

After you verify your fuel pressure you might rebuild the throttle body.  Could be the pressure regulator.  Fairly easy job.

[nativetexan]

Ok, not to repeat myself ;Dbut, I did check the pressure. It is fine until it gets demand. If you open the throttle on it it will drop to zero until you let off. What would cause a sudden drop in pressure when accelerating ?

[VileZambonie]

You are being so vague here with the details. What is the pressure? What year is it? Is it stock? You already had a thread on this? Why didn't you pick up there? All I got out of your video was that it's idling way too high and you're running out of fuel or have a plugged exhaust. Any vacuum leaks or kincked fuel lines?

[nativetexan]

You are being so vague here with the details. What is the pressure? What year is it? Is it stock? You already had a thread on this? Why didn't you pick up there? All I got out of your video was that it's idling way too high and you're running out of fuel or have a plugged exhaust. Any vacuum leaks or kincked fuel lines?

Sorry guys.
I reposted cuz I couldn't find it and I thought it got closed. But I found it. Here is the link:
http://forum.73-87chevytrucks.com/smforum/index.php?topic=18147.msg150980#msg150980

Its a 87 350 with a stock TBI and intake. I cant remember what the pressure was exactly, but I know it was around 14lbs. but When I stepped on the gas to simulate the issue, it dropped down to <5lbs. And sometimes under 1lb. The idle might be high in the video because I didn't let it warm up. IDK. I took the filter out after installing the new motor and blew out the supply line from where the filter was. But not the other lines. What are the other two lines for by the way?