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Topic Review (Newest First)
02-11-2012 03:55 PM
EagleMark No hurt feelings or upset just don't want to help if you find my posts inconveinent or going over a subject again. I know this system like back of my hand, converted it to many differant motors and even have a truck with one from factory I have owned 10 years.

But without knowing fuel pressure, having a scan tool or ALDL cable and laptop, or going over every possible sensor/circut with a DVM your running out of tips and tricks?
02-11-2012 03:45 PM
martee373 Sorry if i hurt your feelings EagleMark but I"ve answered and responded to every question and suggestion i've been given...and i really do appreciate everyones help and suggestions but most of what you've suggested has already been suggested to me such as the ground strap going to the fuel pump and the ones for the block...the only thing i haven't replied about yet is what the condition of the ground strap for the fuel pump because i haven't checked it yet, as i stated in a previous post i have a sneaking suspicion that might be as because when i changed the fuel pump a few years back i noticed the ground strap had been cut and splice back together for some reason, it never concerned me becuase i never had an issues until now. So when i lower the tank to inspect it I'm going to go ahead and clean the mounting surfaces and replace the strap with a unspliced one...once again sorry if i upset you, don't get me wrong i appreciate any and all suggestions and i wasn't trying to be rude but the same suggestions over and over aren't necessary To answer your other post the fuel pump is working i can sit in the truck and hear it come on, the truck is an origianl tbi truck and all 3 of the engine grounds have been checked and the mounting surfaces cleaned
02-11-2012 03:17 PM
EagleMark If it's mine I'll delete it for you and stop tring to help?

But you say you don't have a buck to your name and want some help to fix issues, no volt meter tests, no fuel pressure tests, everyone is trying to help you with tips and tricks and your complaining and wanting to delete posts? you haven't even answered any questions on the tips and tricks given you?



EDIT: Sorry, I guess there's no way to edit or delete posts after time. Your stuck with all this free help!
02-11-2012 09:34 AM
martee373 How do I delete posts on this Forum? I seem to be getting the same suggestions over and over now! Makes things more aggravating lol
02-10-2012 02:03 PM
EagleMark
Quote:
Originally Posted by martee373
Thank you EagleMark I already know hot to pull trouble codes with a paperclip or short piece of wire...but I have no trouble codes to read, the check engine light has been on once since this started. I don't have money to rent a gauge either so I have to do whats within my means. I have a sneaking suspicion that the fuel pump ground might be the culpret, I recall years back when I put a fuel pump in it that the ground wire had been spliced back together before I got to it and since the tank is empty its not much trouble to drop it. I want to inspect the tank and sock anyways to make sure everything is clean. I'll keep this post informed once I do that. I just haven't felt like messing with it the last couple of days lol
Quick check to see if fuel pump is running is a volt meter or just put your hand on tank and listen while someone turns key on, no crank and it should run for couple seconds then turn off. If not tap bottom center of tank where pickup is, key on check again. I have seen sock rot and fuel pump pick up fibers and lock pump causing burned/corroded connections in plug in tank on fuel pump.

If you have to replace pump there are chepies, spend and extra couple bucks for AC Delco or Carter replacement. Carter is my favorite and comes with new plugs, wires and usually a good sock.

There's usaully a ground wire from tank to frame, this too can be an issue, just take it off, clean it up and rebolt. Forget if this was stock TBI truck or conversion but conversion vehicles ususally lack good ground strap from frame to engine block, engine block to body. So on conversions it's always good to ground pump back to block or at least get good ground strap from frame to block...
02-09-2012 11:25 AM
martee373 yup...this forum is helpful to an extent but people really don't read the previous posts to see whats been tried do they?
02-09-2012 08:07 AM
T-bucket23
Quote:
Originally Posted by martee373
I'm working on my 89 gmc sierra its got a throttle body 350...i'm having problems with its idling and acceleration...both issues are not a steady issue, it comes and goes but sometimes it idles real rough and when you put it in gear and give it gas to take off it sputters and acts like it doesn't want to take fuel push the gas down a little further and it clears up and takes off most of the time, every once in a while it will kill the engine. like i said though it doesn't do this all the time. as far as what i've done to it so far, its gotton new plugs, wires, cap, rotor button and fuel filter pretty much all of the sensors and electrical components are new or less than a year old so i'm a little stumped as to what the problem might be. Also as of yet the computer has not given any trouble codes.
Have you checked the EGR to see if it is sticking open sometimes. An EGR valve that is hung open will effect idle quality and low end acceleration.
02-08-2012 07:03 PM
martee373 Thank you EagleMark I already know hot to pull trouble codes with a paperclip or short piece of wire...but I have no trouble codes to read, the check engine light has been on once since this started. I don't have money to rent a gauge either so I have to do whats within my means. I have a sneaking suspicion that the fuel pump ground might be the culpret, I recall years back when I put a fuel pump in it that the ground wire had been spliced back together before I got to it and since the tank is empty its not much trouble to drop it. I want to inspect the tank and sock anyways to make sure everything is clean. I'll keep this post informed once I do that. I just haven't felt like messing with it the last couple of days lol
02-08-2012 03:56 PM
EagleMark
Quote:
Originally Posted by martee373
Thanks for the suggestions Chevytruckguy...I don't have any money to go out and buy a scanner or a manual, i have the basic Chilton manual which is pretty much useless in this situation. I put a motor in it last week so the 3 ground straps that go to the motor are clean as well as the body ground, i'm sure of that much. I'm going to checkout the fuel pump ground and the fuel pump itself and if that doesn't help I'm either gonna sell the truck or send it to the scrapyard, which will likely bring me more than I can sell it for.
here's the free procedure for checking trouble codes stored with a paperclip. Then at bottom of page can download free GM Service manaul in pdf with diagnostics for all codes. You'll need the one for TBI, there is also TPI and V6 available.
http://www.gearhead-efi.com/Fuel-Inj...-CEL-SES-Light

Hope that helps you get going.

You can usually borrow or rent a fuel pressure gauge from parts stores nowadays before you pull tank and don't even know if you have a fuel pressure issue. On your truck it will go in by the fuel filter in middle of truck. No shrader valves on these TBI engines like MPFI...
02-06-2012 04:17 PM
martee373 thanks ssmonty, i'll be inspecting the fuel tank in a couple days when i get around to working on it again, kinda fed up with it so i'm taking a little break and its electronically advanced timing but yes it advances correctly, or i assume its correct, no way to be sure without tapping into the computer
02-06-2012 03:43 PM
ssmonty Could be trash or partially clogged fuel pickup in the tank. I've seen the socks get pretty clogged where they will collapse intermittently.
Have you used a timing light on the balancer to see if the ignition advance is moving freely as you rev it up and down, both mechanical and vacuum, not sticking? Might pull the cap off the dizzy and draw on vacuum hose to see if the vacuum advance moves smoothly.FWIW
ssmonty
02-06-2012 11:18 AM
martee373 northstar T I just took the throttle body off a couple of days ago and did all of that...thanks for the suggestion though
02-06-2012 11:03 AM
Northstar T remove the TB, remove the IAC valve, and clean the gunk from those passages and the tip of the IAC valve with spray carb cleaner and a rag. I think you'll be happy with the results.

Russ
02-06-2012 10:42 AM
martee373 66gmc yes i believe i stated that earlier...new fuel filter plugs wires cap button

dklong i just put the throttle body back on it from cleaning those ports and i have rechecked to make sure i didn't have any leaks, the timing i just set when i put the motor in and i'm pretty sure the distributor is fine as the truck was running great before it sat for a little while in the garage.

chevytruckguy all i want for this truck is for it to run and drive, without i'm never gonna be able to get back on my feet, i have work i can do but i need the truck to get there and i don't have so much as $1 to my name so reguardless of what tools would help, i can't run out and buy a fuel pressure gauge or a computer scanner, its just not an option. I realize its going to be hard to figure out without being able to access the computer but I simply don't have a choice
02-05-2012 09:14 PM
66GMC
You HAVE replaced the fuel filter, right?
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