speedfreak78
Newbie
New guy here. I have this 1993 GMC C1500 305/4l60E and I think 3.08s..haven't actually checked the RPO code yet, but it's a dog. I've been reading this forum for years, finally had to sign up cause i got a head scratcher here i can't figure out and I can't find any post like it.
A little back story...
It was supposed to be my fathers truck, he bought it off the original owner about 15 years ago, who kept the truck cherry. It only had 100K on it. The guy had washed the truck, religiously, weekly... until a trash truck backed into it and took out the drivers fender, door, pillar/cab corner and half the bed. It sat for a couple months after that before my father bought it. I found a matching color, mint condition, door and fender we put on it. I pulled out the door pillar, welded in a new cab corner straightened the bed side out as best i could. Went through the whole truck and replaced anything that was suspect..exhaust, steering stuff, manifold gaskets, brakes and a bunch more I'm forgetting..I had a "friend" who was starting a body shop, and my father got sick, so we decided to help my "friend" out and let him finish the mud work and spray the whole truck in the original 2 tone blue/silver. He knew my father wasn't doing well and there was a time frame to get the truck done. Well..like happens alot.. 3 weeks in the body shop turned into months. At one point the truck was 75% sanded down to bare metal and left outside which pissed me right off. My father passed away during this time which both infuriated me with my "friend" and made dealing with him, legally, a real P'I'T'A. But eventually it got painted and I got it back and parted ways with my "friend"..then it sat for almost 10 years, being randomly started and driven around my property or worked on. I registered it last September and have been driving it since. Dealt with some basic issues on a truck that sat so long. Had electrical issues cause of a bad cell in the battery so it got a new battery. Cleaned up the grounds and some of the wiring connections that had corrosion. New Alternator. New fuel pump/filter. New plug/wires and verified timing.
Ok now the weird issue..or TL;DR...lol..
Occasionally, it drives like something is.... bound up? is the best i can describe it. Step on the gas and the engine sounds like it's trying to rev, but the truck has no acceleration. All sound, no fury. It never throws any codes. The weird thing is I can shut the truck off when it happens, immediately restart it and it's fine for anywhere from a few minutes to maybe 10 minutes, before it happens again. Then shut it off, restart..repeat. Seems like the hotter it gets, the quicker it happens again. I drove it to work most of the winter..about 20 min round trip and it only did it a couple times. Come spring time it started happening more frequently. When it's not happening the truck runs awesome. I'm guessing it's an electrical/ECU issue but without codes..I'm at a loss where to start. Since it runs really good sometimes, I don't wanna just start throwing parts at it. I've already gone over most of the wiring/grounds and had the tranny pan off to check the VB/wiring and it all seems ok? I just downloaded Tunerpro and ordered a cable so I can do live data streaming to watch what's going on when it happens. My W.A.G is restarting it put's it back into open loop where it runs fine until it goes back to closed loop and then a faulty sensor, or maybe ecu programming, is screwing things up.
Any ideas where i should start?
A little back story...
It was supposed to be my fathers truck, he bought it off the original owner about 15 years ago, who kept the truck cherry. It only had 100K on it. The guy had washed the truck, religiously, weekly... until a trash truck backed into it and took out the drivers fender, door, pillar/cab corner and half the bed. It sat for a couple months after that before my father bought it. I found a matching color, mint condition, door and fender we put on it. I pulled out the door pillar, welded in a new cab corner straightened the bed side out as best i could. Went through the whole truck and replaced anything that was suspect..exhaust, steering stuff, manifold gaskets, brakes and a bunch more I'm forgetting..I had a "friend" who was starting a body shop, and my father got sick, so we decided to help my "friend" out and let him finish the mud work and spray the whole truck in the original 2 tone blue/silver. He knew my father wasn't doing well and there was a time frame to get the truck done. Well..like happens alot.. 3 weeks in the body shop turned into months. At one point the truck was 75% sanded down to bare metal and left outside which pissed me right off. My father passed away during this time which both infuriated me with my "friend" and made dealing with him, legally, a real P'I'T'A. But eventually it got painted and I got it back and parted ways with my "friend"..then it sat for almost 10 years, being randomly started and driven around my property or worked on. I registered it last September and have been driving it since. Dealt with some basic issues on a truck that sat so long. Had electrical issues cause of a bad cell in the battery so it got a new battery. Cleaned up the grounds and some of the wiring connections that had corrosion. New Alternator. New fuel pump/filter. New plug/wires and verified timing.
Ok now the weird issue..or TL;DR...lol..
Occasionally, it drives like something is.... bound up? is the best i can describe it. Step on the gas and the engine sounds like it's trying to rev, but the truck has no acceleration. All sound, no fury. It never throws any codes. The weird thing is I can shut the truck off when it happens, immediately restart it and it's fine for anywhere from a few minutes to maybe 10 minutes, before it happens again. Then shut it off, restart..repeat. Seems like the hotter it gets, the quicker it happens again. I drove it to work most of the winter..about 20 min round trip and it only did it a couple times. Come spring time it started happening more frequently. When it's not happening the truck runs awesome. I'm guessing it's an electrical/ECU issue but without codes..I'm at a loss where to start. Since it runs really good sometimes, I don't wanna just start throwing parts at it. I've already gone over most of the wiring/grounds and had the tranny pan off to check the VB/wiring and it all seems ok? I just downloaded Tunerpro and ordered a cable so I can do live data streaming to watch what's going on when it happens. My W.A.G is restarting it put's it back into open loop where it runs fine until it goes back to closed loop and then a faulty sensor, or maybe ecu programming, is screwing things up.
Any ideas where i should start?
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