Engine cranks but no start, put back the old MAF sensor?

2003 GMC SIERRA
111,000 MILES • 6.0L • V8 • 4WD • AUTOMATIC
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LOUD PELLETIER
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  • 39 POSTS
I recently swapped the engine and it worked great after its first week on the road. So I decided to do a check-up to see if everything was connected and I saw that it had a code p0174. I tried to adjust it by changing the MAF sensor and immediately after I started them, I did a wrinkle with and when I turned them off I checked again if the code was gone and not then and put back the old MAF sensor and I tried again then it did not start anymore. it cranks but it did not start but the fuel pump, knock sensor, cam sensor, coils spark plugs, and spark plug wire are changed. Yet I have a good fuel pressure 55-60lbs. The injectors work but despite the new coils and everything else it no longer makes a spark and all the fuse and relays have been checked and they are all Okay. Please help me
Jun 19, 2022 at 10:09 AM
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STRAILER
  • Experienced Mechanic
  • 55,273 POSTS
If the MAF sensor is bad it tells the computer, the engine has no air intake occurring, so it shuts the injectors off. Try to unplug the MAF sensor and see if it starts, if so, get a new MAF sensor. Here are the instructions below on how to change it out. I would get an ACDelco unit from Amazon. Check out the diagrams (below). Let us know what happens and please upload pictures or videos of the problem.

Jun 20, 2022 at 5:45 AM
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LOUD PELLETIER
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But with the old it started perfectly.
Jun 20, 2022 at 7:12 AM
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LOUD PELLETIER
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  • 39 POSTS
I don't have the security light i do not include. I changed cam crank knock sensor it has 12v to injectors pulse and to coils I have no spark and I checked the ground I sand and reinstall, and nothing changed.
Jun 20, 2022 at 7:18 AM
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