To start, I am extremely grateful for advice on this. I have a 2007 Hyundai Accent Hatchback, 2 door. The check engine light was on and the codes were for P0451 and P0453. I was told I could drive it for a bit before needing to fix those codes. A couple weeks later, it went from 60 to 0 on the interstate while driving. There seemed to be a hiccup right before it happened. Lights on dash remained on and still had battery power but it would not start back up. When cranking, the RMP needle jumps once just a tiny bit on the initial crank. Here are the steps I have taken so far: 1. Pulled the Fuel Pump Relay out and swapped with Horn Relay, no change. 2. Checked the fuel pump fuses are good. 3. Checked that the timing belt is not broken. 4. Since I could not hear the fuel pump hum when turning key to the "on" position - And since the pump only hummed if I cranked the engine and tapped the top of the pump with a screwdriver-- I replaced the complete fuel pump assembly thinking that was the issue. I primed the pump by turning the key to "on" waiting a few seconds and then off again- I tried that multiple times. Now with the new fuel pump assembly, it hums when I turn the key to the "on" position but still only crank, no start. I also noticed once I replaced the fuel pump that it does not hum every time when turning the key to the "on" position. I read that it may not hum every time if enough pressure is built? I also noticed when cranking, every 4th crank attempt it seems to hiccup a little but never starts. (Shown in Video) Any advice is appreciated!! I guess my questions are: -Does it sound like the fuel pump assembly was even the issue, if still not starting? -Would the codes for the fuel tank pressure sensor that were showing before it died, cause this issue? -I read about the crankshaft sensor causing issues with starting, but would it cause it to lose power while driving like that?
EDIT: Also- While replacing the fuel pump assembly, one of the bolts holding the retainer ring down snapped. The head snapped off and the rest is stuck in the threaded portion of the "bottom ring" that the retainer ring sits on and is bolted to. The "bottom ring" sits on top of the gas tank- around the outer part of the entry into the gas tank-so there is no chance of the broken part to falling into the tank. But, I am not able to put in a replacement bolt to create a solid seal around the retainer ring. I have read both, that it could create a compression issue and that the other 7 bolts should be enough to create a good enough seal to start the engine.....please help
EDIT: Also- While replacing the fuel pump assembly, one of the bolts holding the retainer ring down snapped. The head snapped off and the rest is stuck in the threaded portion of the "bottom ring" that the retainer ring sits on and is bolted to. The "bottom ring" sits on top of the gas tank- around the outer part of the entry into the gas tank-so there is no chance of the broken part to falling into the tank. But, I am not able to put in a replacement bolt to create a solid seal around the retainer ring. I have read both, that it could create a compression issue and that the other 7 bolts should be enough to create a good enough seal to start the engine.....please help
Video (Click to enlarge)
May 24, 2026 at 10:08 PM
