5.3 Swap crank but no start, Urgent

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Jackslaw64

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First time posting here, sorry if its not formatted perfectly or anything. I just swapped a 05 5.3, with an NV3500 into my 1990 Sierra, followed LT1 website to make custom harness, and fuse block. The problem is that my engine will crank, and will easily start with starter fluid, but dies soon after, (possibly due to the fact that i have to disconnect the MAF to use the starter fluid). Ive checked all the continuity and powers I can think of, injectors and coil packs especially. I wouldn’t normally post this kind of thing, but I have to head back to college in two days, and I’m really on my own here, not a pity story at all, just really need any help I can get.
 

Komet

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Put a noid light on it and see if you're getting fuel injector pulse. Get a datalog and see what the sensors are telling you.

edit: Check fuel pressure as well.
 

0xDEADBEEF

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It will still run with the MAF unplugged. At some point it will set a diagnostic code for that.

It does sound like VATS. Who did the PCM?
 

Jackslaw64

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Put a noid light on it and see if you're getting fuel injector pulse. Get a datalog and see what the sensors are telling you.

edit: Check fuel pressure as well.
Fuel pressure is solid, I don’t have a noid light but I can try and bum a ride to go and get one, I live real far from town or Id just walk.
 

0xDEADBEEF

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You might give him a call and see if he'll overnight you a new PCM. I'm assuming you don't have anyone close by with HP Tuners, if you have to DIY, check out PCM Hammer and Tuner Pro. Maybe you can get Amazon to deliver you an OBDLinkLX by tomorrow. (And hopefully you have a laptop.)

You can check the injectors with a pipe or something, they make a faint clicking sound. I don't recommend this, but with a stock fuel rail you can pull them out of the intake and spray highly flammable mist around.
 

Jackslaw64

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You might give him a call and see if he'll overnight you a new PCM. I'm assuming you don't have anyone close by with HP Tuners, if you have to DIY, check out PCM Hammer and Tuner Pro. Maybe you can get Amazon to deliver you an OBDLinkLX by tomorrow. (And hopefully you have a laptop.)

You can check the injectors with a pipe or something, they make a faint clicking sound. I don't recommend this, but with a stock fuel rail you can pull them out of the intake and spray highly flammable mist around.
Yeah Im stuck in a very rural part of Arkansas, so no one that I can find has access to HP Tuners, amazon can get the OBDLinkX here by next week, I’m going to check these injectors and pray its them, thank you very much.
 

0xDEADBEEF

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If the injectors were sitting for a while they can get stuck. I've been able to save some by using a 9v battery and carb/injector cleaner.
 
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