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Old 05-20-2019, 02:14 PM   #1
HTX86chevy
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starts but dies immediately

5.3 DBW and 4l60e into 72 c10 with Factory tank.

This is my 1st time doing an LS swap.
reworked harness myself using guide from (Brenden/Lt1swap.com)
had PCM done by Brenden also.

walbro 255 inline fuel pump

I have added grounds like crazy including 1 to PCM case

I have swapped fuel regulator 3 times and seem to be getting only 52psi on gauge

when I engage the key, I can hear the fuel pump run and stop after a few seconds. I turn the key to on and the engine cranks, starts and dies after 2-3 seconds. no sputtering or anything, just cuts off.

I don't have the OBD port wired up yet.

Any Ideas? what should be my next step?
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Old 05-20-2019, 03:05 PM   #2
mongocanfly
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Re: starts but dies immediately

Is the maf hooked up?
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Old 05-20-2019, 03:37 PM   #3
HTX86chevy
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Re: starts but dies immediately

Maf is NOT hooked up. Does it need that to run? I don't have a MAF sensor to hook up to. do I need to go get an air box and MAF sensor and hook that up?

Update: Ran out and Pulled MAF from my sons truck. hooked it up and she fired right up and ran perfectly.
I owe you a beer, sir. Thank you so much for taking the time to reply!
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Old 05-20-2019, 09:10 PM   #4
lutronjim
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Re: starts but dies immediately

On my 'connect and cruise' the MAF had to mounted in the middle of at least a 12" straight tube. If I remember it wanted 4" diameter.

I initially bought a pretty chrome pipe from ebay - about 3" diameter. It ran but had a weird throttle response and continually set codes.

Might want to check when you mount yours.
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Old 05-20-2019, 09:32 PM   #5
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Re: starts but dies immediately

Haha...I might take you up on a rootbeer!..
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RIP Dad
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1981 C30 LQ9 NV4500..http://67-72chevytrucks.com/vboard/s...d.php?t=753598
Mongos AD- LS3 TR6060...http://67-72chevytrucks.com/vboard/s...34#post8522334
Columbus..the 1957 IH 4x4...http://67-72chevytrucks.com/vboard/s...63#post8082563
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Old 05-21-2019, 11:02 AM   #6
JJ1972
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Re: starts but dies immediately

Check to see if you have oil pressure sending unit wired to PCM. It will start and then die. I know from experience.
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Old 05-21-2019, 04:19 PM   #7
bigdaddy4x4
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Re: starts but dies immediately

Quote:
Originally Posted by HTX86chevy View Post
5.3 DBW and 4l60e into 72 c10 with Factory tank.

This is my 1st time doing an LS swap.
reworked harness myself using guide from (Brenden/Lt1swap.com)
had PCM done by Brenden also.

walbro 255 inline fuel pump

I have added grounds like crazy including 1 to PCM case

I have swapped fuel regulator 3 times and seem to be getting only 52psi on gauge

when I engage the key, I can hear the fuel pump run and stop after a few seconds. I turn the key to on and the engine cranks, starts and dies after 2-3 seconds. no sputtering or anything, just cuts off.

I don't have the OBD port wired up yet.

Any Ideas? what should be my next step?
was the vats removed ? and check the grounds again
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