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5.3 swap help!

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Old Feb 6, 2023 | 05:34 PM
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jnew07's Avatar
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Default 5.3 swap help!

I’m doing a 5.3 swap but can’t get the thing to start.

1999 z28 ls1 PCM
swap harness, has all the grounds converted to 2 grounds (both checked and they are good.)

Has new fuel.
Fuel lines are ran correct.
Has fuel pressure to the rails.
Has spark at the plugs (in correct firing order).
Timing is correct on the cam.
New cam sensor
New crank sensor
New MAF sensor
New map sensor

VATs have been deleted with HP tuners.

I get an initial pop and a flame and after that’s it’s all cranking no more ignition. Keep trying to crank and then I’m just washing out the cylinders I’ll pull the plugs turn it over dry everything out and repeat the process. Showing no codes… x24 reluctor. Got the correct sensors for the x24 reluctor…… just looking for any kinda help? Thanks!
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Old Feb 6, 2023 | 08:28 PM
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Project GatTagO's Avatar
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From: Little Austin
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Originally Posted by jnew07
I’m doing a 5.3 swap but can’t get the thing to start.

1999 z28 ls1 PCM
swap harness, has all the grounds converted to 2 grounds (both checked and they are good.)

Has new fuel.
Fuel lines are ran correct.
Has fuel pressure to the rails.
Has spark at the plugs (in correct firing order).
Timing is correct on the cam.
New cam sensor
New crank sensor
New MAF sensor
New map sensor

VATs have been deleted with HP tuners.

I get an initial pop and a flame and after that’s it’s all cranking no more ignition. Keep trying to crank and then I’m just washing out the cylinders I’ll pull the plugs turn it over dry everything out and repeat the process. Showing no codes… x24 reluctor. Got the correct sensors for the x24 reluctor…… just looking for any kinda help? Thanks!
A pop and a flame tells me that you may have the coil sub harness installed incorrectly...

Andrew
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Old Feb 6, 2023 | 08:38 PM
  #3  
jetech's Avatar
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From: Dade City, Fl.
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Double check the harness and connections at the crank position sensor. What is the cranking compression?
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