NO start (starts with 1 injector unplugged)
#1
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NO start (starts with 1 injector unplugged)
Yup as mindblowing as that sounds to anyone that knows anything about cars.
Story, Car is a 49 chevy pickup that I have swapped a 5.3 lm7 off of an 04 avalanche. I scooped up engine, tranny, pcm, and wires off the original car, and it ran perfectly fine.
Now Vats has been removed and I have reworked the harness, I have solid power coming into all the coils, injectors, and all the other pink wires at all times!
If I try to start the car I dont get any spark, the second I unplug any injector, any of the 8 wala i have spark and the car will try and start, it sputters hard but if i open up the throttle i can keep it alive for a bit, then plug in the unplugged injector and she smoothens up nicely! I am completely stumped with this
any insight or ideas would be appreciated greatly!
I am assuming it might be a grounding issue but I have no clue as to what else might need ground, The whole rework section has one ground that came off the c2 block, the engine has 2 ground in the back of the block and the one that goes from the frame to the block.
Thanks!!!
Story, Car is a 49 chevy pickup that I have swapped a 5.3 lm7 off of an 04 avalanche. I scooped up engine, tranny, pcm, and wires off the original car, and it ran perfectly fine.
Now Vats has been removed and I have reworked the harness, I have solid power coming into all the coils, injectors, and all the other pink wires at all times!
If I try to start the car I dont get any spark, the second I unplug any injector, any of the 8 wala i have spark and the car will try and start, it sputters hard but if i open up the throttle i can keep it alive for a bit, then plug in the unplugged injector and she smoothens up nicely! I am completely stumped with this
any insight or ideas would be appreciated greatly!
I am assuming it might be a grounding issue but I have no clue as to what else might need ground, The whole rework section has one ground that came off the c2 block, the engine has 2 ground in the back of the block and the one that goes from the frame to the block.
Thanks!!!
#4
According to this. http://www.justanswer.com/chevy/0sa5...nds-truck.html
There are only 2? Is this wrong? Or am i just confused?
There are only 2? Is this wrong? Or am i just confused?
IDK, all the LS1's I know of have three. Try comparing that schematic w/ an 04 F-body or Vette schematic & see if anything jumps out @ you. Looks like either a short to ground or a missing ground. There is an issue w/ a circuit related to starting the car. I'd look @ all start related circuits.
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Everywhere i read everyone says the engine harness has 3 grounds to the block, i know for sure i only have 2 at the back right now bolted up so i will look for another one, it has to be a ground issue i cant come up with anything else that would cause this
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So i took apart the grounds cleaned them good and i can get it to start, takes a litttle while to start, and i have to give it gas ,and runs a bit rough but that might be due to not having a fuel oressure regulator on, ima go get one, a rad so i can keep her on for a while and then report back as I monitor the live data.
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Yea complete accident lol, but she fires right up now gonna monitor her now and make sure everything is working properly. You guys still run dexcool on swaps right?
#12
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I don't use Dexcool on any of my swaps. I do a complete flush of my systems and use the normal green stuff.
If i can't flush the engine before taking it. I will start it up with water. Flush it a few time and the use tge green stuff. Never had a problem if junk building up due to the Dex being in there before.
If i can't flush the engine before taking it. I will start it up with water. Flush it a few time and the use tge green stuff. Never had a problem if junk building up due to the Dex being in there before.
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I don't use Dexcool on any of my swaps. I do a complete flush of my systems and use the normal green stuff.
If i can't flush the engine before taking it. I will start it up with water. Flush it a few time and the use tge green stuff. Never had a problem if junk building up due to the Dex being in there before.
If i can't flush the engine before taking it. I will start it up with water. Flush it a few time and the use tge green stuff. Never had a problem if junk building up due to the Dex being in there before.
Something interesting is going on, I go to fire her up and i notice that she cranks and runs for a quick second shuts off i crank her a bit more and then unless i throttle her for a bit and wait till she gets used to running she wont stay on..
As far as codes I have 6 codes none of which i think are associated,
Maf code since its not in yet,
engine temp using a different sensor,
fuel level,
engine oil pressure low voltage, no idea why?
Malfunction indicator lamp, no CEL light yet
and engine rpm output, i have no tach yet..
she runs great after a while idle is even with what ecu is asking for no misfires nothing
Thanks again
#14
As far as codes I have 6 codes none of which i think are associated,
Maf code since its not in yet,
engine temp using a different sensor,
fuel level,
engine oil pressure low voltage, no idea why?
Malfunction indicator lamp, no CEL light yet
and engine rpm output, i have no tach yet..
she runs great after a while idle is even with what ecu is asking for no misfires nothing
Thanks again
Maf code since its not in yet,
engine temp using a different sensor,
fuel level,
engine oil pressure low voltage, no idea why?
Malfunction indicator lamp, no CEL light yet
and engine rpm output, i have no tach yet..
she runs great after a while idle is even with what ecu is asking for no misfires nothing
Thanks again
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as far as the temp sensor? would it cause a difference?
after a few more hard starts and replugging in the fuel gauge, it now starts instantly
has me a bit worried! but its hopefully gone
Last edited by mannythechamp; 01-10-2015 at 01:54 PM.
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You guys were absolutely right, I decided to keep the oem sensor the pcm reads actual temps now instead of -38 lol!
Thanks for all the help and insight!