Hey guys!
I tried to start the TPI up on my GMC today, but it won't fire. My timing light tells me that I've got spark, and I've got air, so I can only figure that it isn't pulsing the injectors. I checked the power to them, and they are getting 12 volts, so I can only assume that the ECM has decided not to pulse the injectors for some reason.
Anyone have any ideas?
I tried to start the TPI up on my GMC today, but it won't fire. My timing light tells me that I've got spark, and I've got air, so I can only figure that it isn't pulsing the injectors. I checked the power to them, and they are getting 12 volts, so I can only assume that the ECM has decided not to pulse the injectors for some reason.
Anyone have any ideas?
Senior Member
Check the oil pressure switch. Are you sure you are getting fuel? Have you checked the fuel pressure?
Does it chug at all, or just crank solidly with no start?
Does it chug at all, or just crank solidly with no start?
I figured out why the injectors were not firing -- My injector wiring had a dead short in it, causing both poles of the injectors to be positive. I had to tear the whole intake off to get at the wiring, cause I installed my injectors with the wiring plugs pointing to the inside of the intake, rather than the outside like stock.
So yeah, decided I wanted to check on my wiring fix, and left the injector rail sitting on the tire (no inner fenders) turned the ignition on and off a few times to make sure that it was well primed, then hit the starter and POOF. Big cloud of smoke from the general area that the injector rail, and other sensor plugs that were not currently hooked up were sitting. Lost all power in the truck, so it must have blew the main fusible link, rather than blowing any of the fast burn fuses that protect every single circuit in the truck.
That sucks hardcore, cause I have to pull my passenger side header off to get at the starter to replace that blown fusible link, which means I need a new deadsoft collector gasket, new manifold style exhaust gaskets, and a new fusible link. Along with a whole lotta work.
Its been six months since I started this swap, maybe someday I'll actually hear my truck run again
So yeah, decided I wanted to check on my wiring fix, and left the injector rail sitting on the tire (no inner fenders) turned the ignition on and off a few times to make sure that it was well primed, then hit the starter and POOF. Big cloud of smoke from the general area that the injector rail, and other sensor plugs that were not currently hooked up were sitting. Lost all power in the truck, so it must have blew the main fusible link, rather than blowing any of the fast burn fuses that protect every single circuit in the truck.
That sucks hardcore, cause I have to pull my passenger side header off to get at the starter to replace that blown fusible link, which means I need a new deadsoft collector gasket, new manifold style exhaust gaskets, and a new fusible link. Along with a whole lotta work.
Its been six months since I started this swap, maybe someday I'll actually hear my truck run again
Senior Member
You have to pull the header 
Anyway, I'm planning on doing a TBI -> TPI swap in my Fullsize... don't scare me off
Anyway, I'm planning on doing a TBI -> TPI swap in my Fullsize... don't scare me off
A 2wd would be far easier than an old 4x4 with a solid front axle like mine is. I can just barely sneak my hand up into there, but there is no way I could possibly solder a new fusible link in with the header still in place. So I'll probally wind up pulling off my outer fender to make it easier to solder in there.
If I had just taken a better look at that injector wiring harness like I had done on all the rest of my wiring, it probally would have fired right up first try, but things just never work out like that for me =/ I mean, I had issues getting my front shocks on lol
If I had just taken a better look at that injector wiring harness like I had done on all the rest of my wiring, it probally would have fired right up first try, but things just never work out like that for me =/ I mean, I had issues getting my front shocks on lol
Well, I lucked out this time guys.
It winds up that the marret came off of the wire I have on my positive terminal for my electric fans, and touched the frame. Made a lot of smoke, and a lot of noise. My truck has an odd quirk, if you ever short anything out, the negative terminal immediately looses it's connection until you twist it a bit. I totally forgot about that, and thought that I blew my fusible link. Gave the negative terminal a quick turn, and and suddenly everything came back.
Tommorow I'll go get new gaskets (the old ones got soaked in coolant, won't be any good) and put it back together, see if I can get some fuel to pulse out of the injectors
Maybe the old girl will run yet, lol
It winds up that the marret came off of the wire I have on my positive terminal for my electric fans, and touched the frame. Made a lot of smoke, and a lot of noise. My truck has an odd quirk, if you ever short anything out, the negative terminal immediately looses it's connection until you twist it a bit. I totally forgot about that, and thought that I blew my fusible link. Gave the negative terminal a quick turn, and and suddenly everything came back.
Tommorow I'll go get new gaskets (the old ones got soaked in coolant, won't be any good) and put it back together, see if I can get some fuel to pulse out of the injectors
Maybe the old girl will run yet, lol