Make and Model: 1994 GMC Vandura G2500, 5.7L V8 Engine, 162k Miles, Automatic, Private Seller. (this is going to be a lil long, I apologize)
Edit: I don't have a code scanner but when you turn it on, there's a Check Engine light, when you start the van, it's gone. No lights at all.
Bought it last August and it ran just fine, the guy drove it to the meet up spot just fine. Started it up just fine. Engine sounded great. A few weeks later, I buy it for 3500.
An important note is that this Van's Electrical had been redone and then redone. It's a rats nest in there. I'm assuming the old Fuse Box malfunctioned and so the guy who had it before the guy I bought it from, rewired another 2 tinier fuse box's, to the old one. He also removed the Key Ignition and now it's Flip Switch to turn it on, and a button to Start the Engine.
My first fix came about a month after I bought it, It wouldn't hold a charge and kept dying. So, replaced the battery and the alternator. It still kept dying and couldn't hold a charge. So, I installed a Kill Switch. The thought process being that if there was a Parasytic Leak, that would prevent it. It ran good for another month then randomly started not Starting. I fixed the wire connecting the Starter to the Ignition and then fixed the Ground Wire(They were both kind of old) same issue, i removed the Kill Switch and it ran good for another 3 weeks to a month. Well, then my dad used my van to jump his big'ol deisel truck and somehow blew the alternator. We tested that with a Multimeter and lo and behold, wasn't putting but 12.1 out to the battery.
Installed a new alternator(this time a 140 instead of a 105) about 2 weeks ago. Still had the problem with it not starting, noticed a wire wasn't connected to the battery and was just dangling. Reconnected that and it starts just fine now, runs great. The day I installed the stronger Alternator, it died in the middle of the road though, so that was fun. Hasn't done it since, I drive it everyday to and from work(It's only like, a mile.). Also, I noticed a bit of damage on the Battery Terminals. My dad says thats probably just corrosion but It looks like Melting to me, can a short even cause the terminals to melt in seemingly random spots?
TLDR: I'm doing my best but have never worked on a car before. I know I need a new fuse box but does it have to be one from the same vehicle? I just watched the video about checking the Fuel Pump and such as well. Any tips are appreciated, I was even tempted to just buy as many new parts as I can, Spark Plugs, new starter ect. Oh, there's also sometimes a very loud sound, almost like smacking a hammer on metal when it starts. It's EXTREMELY rare, I've only heard it twice since I got it.
1994 GMC Vandura G2500
Buying a 32-year-old vehicle with a borked electrical system is probably not the best idea in the world, especially if you are not familiar with doing your own repairs. Hopefully you didn't pay much for it.
I don't have a code scanner
You will ultimately need a code scanner for diagnostic purposes. Since that vehicle is OBD1, this is the most economical scan tool:
but when you turn it on, there's a Check Engine light, when you start the van, it's gone.
Check engine light with ignition on and engine not running is normal behavior.
I know I need a new fuse box but does it have to be one from the same vehicle?
How do you know you need a new fuse box? Custom wiring is always a possibility but the simplest method would be to install the same type. (GM probably used the same fuse box on a wide variety of vehicles.)
I was even tempted to just buy as many new parts as I can, Spark Plugs, new starter ect.
Not a good idea, that is called the "parts cannon", that can be a very expensive approach and it rarely produces a good result. Replace parts only if they test as being bad.
there's also sometimes a very loud sound, almost like smacking a hammer on metal when it starts.
That does not bode well. Hopefully it is not an internal engine noise.
Basically you are going to need to trace out your electrical faults using wiring diagrams. You can find a repair manual for that truck at the link below, which includes sections on electrical diagnosis:
@chucktobias Not too to much 3500 and I was completely prepared to have to put atleast 2000 into it. I wouldn't say it's Borked. It's very poorly rewired and looks like a mess but everything inside does work(Minus the AC Compressor, need a new one of those.). One of those Jerry Rigged kind of things. I'm assuming it needs a new Fuse Box because the original one has about 15 wires running off of it to 2 definitely not stock Fuse Box's that are much smaller. He wouldn't have had to do that if the original worked, I assume. So, gotta get a new one and redo the wiring. Thank you for telling me to check other GM Vehicle's, I wasn't sure where to look honestly and I had a hard time trying to find one that looked similar online. I don't think it's internal engine, and, it is still a very rare sound. I've only heard it twice in the last 8 months since having it. And I can't thank you enough for that link to Lemon-Manuals. I couldn't find any diagrams at all and that was holding me back SO MUCH.
Edit: That video is a godsend as well, thank you so much!
@chucktobias The only thing it was doing when I did that Code trick was giving the 12 Code, which seems to mean that it's running the Diagnostic. Is it okay to assume that if it doesn't give me a code after three sequences of 1 and 2, that it doesn't have a code to give me? So any problems will likely be related to things the computer doesn't have a sensor for? Or, maybe a sensor is broken?
I personally have not used the CEL flash codes because I have a Tech2 scan tool, which is the factory scanner for GM vehicles from around 1990 to 2010. The shop manual at lemon-manuals.la includes a listing of all trouble codes for your vehicle. Note that "12" is not directly listed, however towards the bottom of that page Chart "A2" does discuss what it means when pulling flash codes:
@chucktobias Other google searches and reading through that a bit seem to indicate that there aren't any codes for it to give me. I guess that's good, maybe I should check to make sure the Fuel Pump is good? There's a code for if the Voltage is low on it(54). Maybe that's why it died in the middle of the road afew weeks ago. I guess I should also try and fix the Fuel Pressure Guage as well. That'll be a good start! Thank you so much for the help! My goals now are to get a new Fuse Box so that the wiring will be easier to work on later and do all my regular maintenance.
Depending on accessibility it should be fairly simple to verify the voltage reaching the fuel pump and whether the pump is operating. Also see the troubleshooting section of the site FAQ for dealing with a no-start problem. (A quick, simple test is to spray some starting fluid into your intake and crank the engine. If the engine fires up briefly you have spark. If it doesn't fire up you don't have spark. This assumes the engine is otherwise OK internally,)
Code 12 means end of codes
