Im stumpped

[Paulscrawler78]

Its not letting me upload the video from my cell phone

 

[Jims86]

Its not letting me upload the video from my cell phone

you may have to e mail it to yourself, then load it into photobucket, and post a link.

 

[Paulscrawler78]

Loading to photo bucket now

 

[Paulscrawler78]

http://static.photobucket.com/playe...lscrawler/photobucket-11360-1351560947452.mp4

 

[towjoe]

I had my 89 V3500 do about the same thing. It would start and rev up without load, but wouldn't run under a load. I replaced everything from the injectors to the computer and about everything else under the hood. Like Jim said it was the fuel line between the pump and sending unit on not one but both of my tanks. I spent over $500 on parts because it never threw a code over a $.49 peace of hose.

Have you tried Jims86 cure yet?

 

[Paulscrawler78]

Not yet

 

[Jims86]

He has the 88 tank and may try to plumb it up to the 87 throttle body, and power the pump with a battery while the tank sits on the ground next to the truck.
The 88 Pump has been recently replaced

 

[Paulscrawler78]

Did the video work???

 

[Jims86]

I think Joe saw it, but my iPad wont play it.

 

[Paulscrawler78]

<a href=http://s1148.photobucket.com/albums/o578/Paulscrawler/?action=view&current=photobucket-11360-1351560947452.mp4 target=_blank><img src=http://static.photobucket.com/player.swf?file=http://vid1148.photobucket.com/albums/o578/Paulscrawler/photobucket-11360-1351560947452.mp4 border=0 alt=></a>

 

[towjoe]

I never got it to load. I'm going by his original post

 

[Paulscrawler78]

I'll figure out how to post a better link for u all tomorrow today has been crazy

 

[Jims86]

Ok, I was able to download it.
I think using the 88 tank as a test feed would be the best bet right now.
This is really just an engine replacement, not a swap to EFI from carb. So before we try to dig too deep, I would at least like to see how the New pump in the 88 tank will run it. If it clears up on that tank, then I say drop the 87 tank, and pop the 88 up in there.
Of course, pull the pump out of the 87 just to see whats up.

 

[Paulscrawler78]

Ok so you was able to hear what happens when I try to full throttle the truck now keep in mind when I took that video the map sensor was unplugged so that I was able to idle the motor and I won't be able to run the test you have explained to me until Wednesday as I have school tomorrow. Also did you get my text message I sent to you Jim?

 

[HotRodPC]

Here is the diagram page on Gearhead.
Enjoy!
http://www.gearhead-efi.com/Fuel-In...ECM-Information-42&p=2205&viewfull=1#post2205

Thanks ******** !!! J/K.. J/K !!! Now just another forum I have to register to so I can see the diagrams? Can you snag'em and bring'em over? I don't care if you put a little, Compliments of TunePro or whatever so they get some recognition.

Is the motor stumbling at all as it's idling up and down? This sounds like one of those things where something is not right, and the computer is compensating making an adjustment, the idle goes up, then the computer realizes, NO don't do that, so it's chasing the problem whatever it is which is confirmed with idling when the MAP is disconnected. Vac Leak would have been my first guess. Reason I ask if motor is stumbling on low idle and it might be, and the ECM is bring the idle up to keep it from stalling, but a stuck open EGR valve will cause a big internal vac leak that you won't find with the normal spraying carb cleaner or starting fluid around the intake, TBI base etc. And for giggles can you swap the IAC off that other truck and see if that makes a difference?