TheTruckOfTheseus
Newbie
i’ve seen a lot of posts that have given me good ideas of where to start, but i have not seen anything exactly like what i’m dealing with. i hope i’m not typing too much, just want to give y’all every relevant detail
so i have a ‘98 ecsb k2500 5.7 farm truck that i bought with ~202k miles and drove it ~2 hours back to my house. the next day when i went to drive it, it was sputtering and stalling but only at lower rpms. it was driving fine when i test drove it, and during the drive down, but i think the drive home was the straw that broke the camels back. long story short, by the advice of a couple of my more mechanically inclined “friends” i replaced the IAC, TPS, MAF, IAT, spark plugs, etc, all to find out using a $2 bottle of C&C cleaner that it was just the o-ring around the spider injector assembly.
we replaced the upper gaskets and cleaned the throttle body while we were in there, and the truck was running great until recently, when it just suddenly died on my way to work. the rpms went from ~2k, down to zero, back up to 2k, then back down to zero and it coasted to a stop all in the span of about 4 seconds. luckily i had just passed my girlfriend’s uncle, who is an actual mechanic (and the one who helped me discover and fix the aforementioned o-ring problem). he told me to try to start it again and said he couldn’t hear the fuel pump, which i thought was odd because i had a new fuel pump installed in march (this happened in mid august). we towed it to a nearby parking lot, he gave me a ride to work, and when i got off we went back to tow it. when we got it home, i turned the key to show them what it was doing and it fired right up, and ran fine for about five minutes until i cut it off. super weird, but i didn’t think too much of it, just chalked it up to bad gas as moved on.
then about a month or so later, i drove from work to the store (like a 3 minute drive), went in for about 5 minutes, then when i came out, it wouldn’t start. thought it might be the relay, so i had a friend that was nearby pick one up for me, to no avail. i noticed the ground on the frame right next to the tank was looking pretty rusty so i cleaned it up, and nothing. i did notice that the wiring harness was pinched between the tank and the frame of my flatbed, so i finally knew what the problem was. about that time, a buddy of mine who i hadn’t thought to call (the “friends” from earlier didn’t bother to pick up) pulled up and offered to tow me home. he said to put it and neutral so we could roll it back, and i said here, let me just start it and we laughed. then it actually started (after sitting for ~1 hour) and i drove home without a problem. i replaced the harness and all was well again, up until a couple weeks ago, when it crank, no started at work, and the fuel pump would not prime no matter what i tried. then after sitting for a couple hours, it worked just fine again.
finally, a few days ago when my dad and i were headed into town, it died (this time was just a slow decline to 0 rpms) and no finagling with the wires or fuses or relays would get it to start. then after waiting about 30 minutes it started fine.
as i sit in the truck right now, it’s priming and starting great, and i tested something i read on another post about removing the fuel pump relay while it’s running and how it should continue to run due to the oil pressure switch i think. when i unplugged the relay, the truck immediately lost power and turned off after about 2 seconds. so i’m wondering if that is a surefire way of knowing that switch is bad and then knowing if that could be why the truck is having this problem
Update: thank you all for the advice and insight, some of this stuff i never would have thought of. found information regarding the underhood fuse box here, so i’m about to dig into that now, and will post pictures. also i’m going to start the truck and let it build up oil pressure for longer to get a better “test” of the OPS
Update #2: Texas decided to storm all day so between that and other errands I didn’t get to do much besides watch some Youtube videos and read more posts here. I’ll get with my mechanic tomorrow and see what he thinks regarding everything; the relay and all connections relating to it, the crank position sensor, and the oil pressure switch
so i have a ‘98 ecsb k2500 5.7 farm truck that i bought with ~202k miles and drove it ~2 hours back to my house. the next day when i went to drive it, it was sputtering and stalling but only at lower rpms. it was driving fine when i test drove it, and during the drive down, but i think the drive home was the straw that broke the camels back. long story short, by the advice of a couple of my more mechanically inclined “friends” i replaced the IAC, TPS, MAF, IAT, spark plugs, etc, all to find out using a $2 bottle of C&C cleaner that it was just the o-ring around the spider injector assembly.
we replaced the upper gaskets and cleaned the throttle body while we were in there, and the truck was running great until recently, when it just suddenly died on my way to work. the rpms went from ~2k, down to zero, back up to 2k, then back down to zero and it coasted to a stop all in the span of about 4 seconds. luckily i had just passed my girlfriend’s uncle, who is an actual mechanic (and the one who helped me discover and fix the aforementioned o-ring problem). he told me to try to start it again and said he couldn’t hear the fuel pump, which i thought was odd because i had a new fuel pump installed in march (this happened in mid august). we towed it to a nearby parking lot, he gave me a ride to work, and when i got off we went back to tow it. when we got it home, i turned the key to show them what it was doing and it fired right up, and ran fine for about five minutes until i cut it off. super weird, but i didn’t think too much of it, just chalked it up to bad gas as moved on.
then about a month or so later, i drove from work to the store (like a 3 minute drive), went in for about 5 minutes, then when i came out, it wouldn’t start. thought it might be the relay, so i had a friend that was nearby pick one up for me, to no avail. i noticed the ground on the frame right next to the tank was looking pretty rusty so i cleaned it up, and nothing. i did notice that the wiring harness was pinched between the tank and the frame of my flatbed, so i finally knew what the problem was. about that time, a buddy of mine who i hadn’t thought to call (the “friends” from earlier didn’t bother to pick up) pulled up and offered to tow me home. he said to put it and neutral so we could roll it back, and i said here, let me just start it and we laughed. then it actually started (after sitting for ~1 hour) and i drove home without a problem. i replaced the harness and all was well again, up until a couple weeks ago, when it crank, no started at work, and the fuel pump would not prime no matter what i tried. then after sitting for a couple hours, it worked just fine again.
finally, a few days ago when my dad and i were headed into town, it died (this time was just a slow decline to 0 rpms) and no finagling with the wires or fuses or relays would get it to start. then after waiting about 30 minutes it started fine.
as i sit in the truck right now, it’s priming and starting great, and i tested something i read on another post about removing the fuel pump relay while it’s running and how it should continue to run due to the oil pressure switch i think. when i unplugged the relay, the truck immediately lost power and turned off after about 2 seconds. so i’m wondering if that is a surefire way of knowing that switch is bad and then knowing if that could be why the truck is having this problem
Update: thank you all for the advice and insight, some of this stuff i never would have thought of. found information regarding the underhood fuse box here, so i’m about to dig into that now, and will post pictures. also i’m going to start the truck and let it build up oil pressure for longer to get a better “test” of the OPS
Update #2: Texas decided to storm all day so between that and other errands I didn’t get to do much besides watch some Youtube videos and read more posts here. I’ll get with my mechanic tomorrow and see what he thinks regarding everything; the relay and all connections relating to it, the crank position sensor, and the oil pressure switch
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