Should i fix the TBI or go to carb? And what's this wire?

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AuroraGirl

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Yes, i did. All are fine
if its on the thermostat housing or next to it, then false
And if its onl the original grounds, almost certainly false. GM was shy with grounding and any corrosion and resistance puts them in the not-enough category. lol
 

Bextreme04

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This sounds exactly like poor/corroded connections. Do you have new power and ground cables on it from the battery? Have you been running continuity checks on the wires? Voltage drop checks? Continuity check will tell you if you have a good connection, voltage drop will tell you whether you have ENOUGH of a good connection. If you don't have enough of a good connection, you could be dumping voltage spikes through the system and back feeding through into other systems
 

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This sounds exactly like poor/corroded connections. Do you have new power and ground cables on it from the battery? Have you been running continuity checks on the wires? Voltage drop checks? Continuity check will tell you if you have a good connection, voltage drop will tell you whether you have ENOUGH of a good connection. If you don't have enough of a good connection, you could be dumping voltage spikes through the system and back feeding through into other systems
Reading this reply says a lot. Not related the OP's issue, but it probably explains why my speedometer on my jeep acts wonky. It's been hit and miss for a couple years now, and new VSS usually works normal for a few weeks at best. Right before T-Day I cleaned a bunch of connections, took it for a test drive and it worked perfectly. The next morning fired it up and the speedometer went to 85 mph while we sat there in the driveway! I will be checking connections now, instead of just cleaning them.
 

AyWoSch Motors

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Before anyone gets upset or says 'that was stupid', id like to say, i have no personal issues with TBI. I respect it. I have many GMT400s that have TBI and they run very well. No complaints.
I also have alot of patience with solving problems. Will usually spend alot of time to do things "the right way".
This truck has used that up.

I thank you to everyone who has attempted to help repair the old system, and i may very well use that info on something else down the road.

today I decided im am no longer going to attempt to fix this nightmare fuel injection, and instead have solved my issue another way....
 

AyWoSch Motors

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I bit the bullet and said "Bye bye TBI, hello carburetor!"
Problem solved. A least that part of it.
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AyWoSch Motors

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After a good cleaning, and a dry fit of the intake.
Looks like its going to go well.
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Redfish

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While I was really hoping you would get this fixed...I know exactly where the original air filter housing, the plastic snorkel and any vacuum hoses associated with the EGR valve need to go.

;)
 

AyWoSch Motors

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While I was really hoping you would get this fixed...I know exactly where the original air filter housing, the plastic snorkel and any vacuum hoses associated with the EGR valve need to go.

;)
You want any of that or just the entire setup, let me know..
 

JoeFox

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When you think you've checked everything, take the computer out and have it checked or just replace it.
I have an '87 r3500, when I got it the fuel system was completely torn apart. I put it back together and it turned out all that was wrong with it was the computer.
 

AyWoSch Motors

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Well the install went well, no issues.
Got everything hooked up and on. Figired up all my fuel lines, vacuum lines, as pcv hookups. Filled the bowl on the carb and stated it up.
It runs!! Ran for about 30-40 seconds, sounded great. Nice and smooth. Happy i went with carb.
No i just have to figure out the electric pump and put it back together.
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Here are some homemade wedge washers i made for the bolt pattern angle difference, and how they worked out...
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Well the install went well, no issues.
Got everything hooked up and on. Figired up all my fuel lines, vacuum lines, as pcv hookups. Filled the bowl on the carb and stated it up.
It runs!! Ran for about 30-40 seconds, sounded great. Nice and smooth. Happy i went with carb.
No i just have to figure out the electric pump and put it back together.
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Here are some homemade wedge washers i made for the bolt pattern angle difference, and how they worked out...
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Very nice work on the wedge spacers!
 

Hunter79764

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You have a reliable pump and return system with the factory TBI stuff, use it. Put a bypass regulator up front for 4 psi or whatever is needed on your carb, return through the stock return line, and you're set. Worst case when you remove the computer etc, you may need to run a new ignition wire to the fuel pump relay. I can't remember on this setup, but if the fuel pump relay circuit goes through an oil pressure switch, I'd keep it there, good safety margin.
 

AyWoSch Motors

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You have a reliable pump and return system with the factory TBI stuff, use it. Put a bypass regulator up front for 4 psi or whatever is needed on your carb, return through the stock return line, and you're set. Worst case when you remove the computer etc, you may need to run a new ignition wire to the fuel pump relay. I can't remember on this setup, but if the fuel pump relay circuit goes through an oil pressure switch, I'd keep it there, good safety margin.
Pump that was in it crapped the bed.
 

Ricko1966

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But a good factory intank pump and a holley 12-881 regulator is better than just about any other pump you can buy. I've tried almost all of them. Mr gasket 12s on a burb, life expectancy here to stuck 100 miles from here. Unknown pump 85 c10 DOA. replacement airtex lasted 2 weeks. Facet pump worked longest but still died way before my intank pumps have died. Best thing about the facet was it didn't leave me stuck,I could smack it with a wrench and it would start working again. In fairness to the airtex pump,when I called Airtex they told me Rockauto is not an airtex distributor so if they sold me the pump it was overstock from who knows where. The older pumps won't tolerate the ethanol in the fuel. The airtex I replaced it with is working fine,but I did get crazy creative on the install to make sure it could never start dry.
 
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Ricko1966

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I'm sure the next question is going to be how did I install it. I installed it on a bracket by the tank but lower. pump inlet side I used the biggest metal filter I could find mounted vertically so it acts as a reservoir. Pump outlet I put a hot wheels style loop in the fuel hose so the pump is always full of fuel. Pump is angled outlet side slightly up like 10 degrees. A loop in the fuel hose just like a hot wheel track but only about 6" in diameter.
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