Pump prime loop and starter clunk (video)
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Pump prime loop and starter clunk (video) 280z, Gen 3 LS1, 4L80e, FiTech EFI
Video shows symptoms. Drove the car to a friend's house, camped out in it overnight, used the battery to run a fan. Battery wept and humidity made a lot of corrosion underneath, but the wires are good.
Bought a new battery and swapped it out, same symptoms.
Also tried jumping it with another V8 before swapping battery, to no avail.
Tried starting in P and N.
As you can see from the video, it builds fuel pressure in-between 20 and 40 PSI, but then just keeps looping that. It never stops priming and never reaches the desired number. The engine never turns over and the starter always clunks. It feels like it's being stopped by something that isn't the starter or motor though. Very violent clunk.
Absolutely no symptoms from starter or fuel pump. Prior to this, car was running well. FiTech is showing no codes but I have a battery disconnect switch that I use every time I park so it probably won't be showing codes.
Has anyone come across anything like what the video shows? The ticking sound or the looping fuel priming?
TECH Fanatic
Joined: Jul 2022
Posts: 1,032
Likes: 389
From: Alaska
Injector(s)stuck OPEN, you've filled a cylinder with fuel, hydrolocked engine.
Pull all 8 spark plugs immediately, turn engine manually one full revolution.
Replace spark plugs, install FULLY CHARGED battery, and hope for the best.
Pull all 8 spark plugs immediately, turn engine manually one full revolution.
Replace spark plugs, install FULLY CHARGED battery, and hope for the best.
If you are correct, you forgot to tell him that an immediate oil change will also be necessary, as the oil pan will be full of fuel/oil mix.
