So apparently that bad injector was the issue? If you are really curious, could always swap injectors into your old TBI. I suspect you are just happy with it working again. 
CK5
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TBI noinjector spray, failed noid test
- Thread starter Josue
- Start date
4xcrazy
3/4 ton status
I've been watching this, interesting. My burb back in Indiana it only there because of this similar issue. Randomly shuts down, no injector pulse, no noid lighting. I've done a few different modules, removed the harness twice, changed out the computer. Still left me stranded in St.Louis on my drive back here after I thought I fixed it.
I really didn't suspect my injectors because they are really fairly new, being less than 2 years, if I find this to be the issue, I'm going to be pissed, especially at aftermarket parts companies for not being able to build quality parts but still charge out the ass for them. I even bought NEW ones, from Napa, not rebuilds.
I was leaning more towards my distributor because it always seemed like whenever I messed with anything in that area, wiring or the dizzy itself, the injectors would start spraying.
I really didn't suspect my injectors because they are really fairly new, being less than 2 years, if I find this to be the issue, I'm going to be pissed, especially at aftermarket parts companies for not being able to build quality parts but still charge out the ass for them. I even bought NEW ones, from Napa, not rebuilds.
I was leaning more towards my distributor because it always seemed like whenever I messed with anything in that area, wiring or the dizzy itself, the injectors would start spraying.
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I think what happens (no electrical wizard) is that the bad injectors overload the ECM's injector drivers, and however that all is supposed to work, stops.
Not necessarily your problem, but it's something to look out for. I had my pickup coil die, and from the looks of it, sitting is really bad for those things...the windings were in horrible condition from corrosion.
Not necessarily your problem, but it's something to look out for. I had my pickup coil die, and from the looks of it, sitting is really bad for those things...the windings were in horrible condition from corrosion.
txfiremank5
1/2 ton status
I just had an issue much like this on my 89 k5. Except I was getting a pulse with the connections with the tester. Put a screw driver to the injectors while cranking, and no clicking noise coming from them. A little tapping on the injectors and it fired right up. Had me stumped for a bit, but it seems the injectors just got stuck after the last trip until the next. Gas was probably getting a little stale. Sure made for some head scratching.
Josue
Registered Member
I think sitting is also horrible for the trucks
Truck sat 3 years until I bought it and finished the swap and everything, first time around when i first made the wiring harness truck ran and everything. Broke the crate engine in as per intructions, then nothing, truck never turned on after that :/
Started to look at my grounds,
tested all PCM grounds, all good
Tested power going to PCM, all correct, both ign and constant
Checked with noid light, no flashing meaning no ground pulse activation
Replaced icm with new from napa, still nothing
Tested wires from ECM to icm, all ohmed good
Tested the wires to ground, none were grounding out
Hooked everything up and tested the injector harness ECM side and checked with voltage to see if maybe it was cross with a hot wire, still nothing :/
Checked fuel pressure and had pressure, added 7 gallons of gas, new fuel filter
I was still getting spark, would start with fuild in the intake
So what was left that I could think before lighting the truck on fire? Injectors... Ohmed the injectors and were at 1.4 and 0.3, minimum at 1.3, and when the PCM detects one of those faults it won't start or operate until the problem is fixed, it couldn't be a ect, it would just over or under fuel.
Replaced the entire TB hooked up some jumper cables, and BAM.. Truck started right up
I'm gonna guess the injector shorted it self out and was sending voltage to the ECM going into a limp mode to protect, because there was no resistance to take up the voltage because the injector failed and was going straight to the PCM
TRUCK RUNS... Finally
Truck sat 3 years until I bought it and finished the swap and everything, first time around when i first made the wiring harness truck ran and everything. Broke the crate engine in as per intructions, then nothing, truck never turned on after that :/
Started to look at my grounds,
tested all PCM grounds, all good
Tested power going to PCM, all correct, both ign and constant
Checked with noid light, no flashing meaning no ground pulse activation
Replaced icm with new from napa, still nothing
Tested wires from ECM to icm, all ohmed good
Tested the wires to ground, none were grounding out
Hooked everything up and tested the injector harness ECM side and checked with voltage to see if maybe it was cross with a hot wire, still nothing :/
Checked fuel pressure and had pressure, added 7 gallons of gas, new fuel filter
I was still getting spark, would start with fuild in the intake
So what was left that I could think before lighting the truck on fire? Injectors... Ohmed the injectors and were at 1.4 and 0.3, minimum at 1.3, and when the PCM detects one of those faults it won't start or operate until the problem is fixed, it couldn't be a ect, it would just over or under fuel.
Replaced the entire TB hooked up some jumper cables, and BAM.. Truck started right up
I'm gonna guess the injector shorted it self out and was sending voltage to the ECM going into a limp mode to protect, because there was no resistance to take up the voltage because the injector failed and was going straight to the PCM
TRUCK RUNS... Finally
