Fuel Pump? Help!

blackout881 · January 29

Hey all,

Been a while since I've been on this forum, probably a good thing! But today I went out to start my 2019 5.3 Sierra with 55k and it just spun and spun to the point I was panicking to push the button to get it to stop. Ironically enough, the last time it was driven was one week ago to the dealer for routine maintenance. Also stopped and filled up the tank on the way home...So truck has been sitting one week in below freezing temps.

I put a charger on the battery and confirmed voltage was good. Also beat on the starter for the hell of it.

The main symptom I can immediately notice is when you open the door, there isn't that "jet engine" like sound of the fuel pump priming. So I am thinking its fuel pump related, or I got bad gas and it froze up in the temps here in NY right now.

Has this happened to anyone else? I do have a second car (Bolt EUV) although my commuter its not what I want during the winter snow, I need to get to work no matter what.

Any way you guys could help me in my driveway without having it towed to the dealership would be great, I don't mind getting my hands dirty.

Thanks!

Edited January 29 by blackout881

Niklasbraun · January 30

Considering the recent maintenance and fuel fill-up, your suspicion about the fuel pump or the possibility of bad gas freezing up seems plausible. If you're up for it, give the fuel pump relay and fuse a quick check. Sometimes, the cold can affect these components. Since you're hands-on, you could also try adding a bit of heat around the fuel pump area (be cautious, though) to see if it changes anything. If these don't yield results, it might be worth hooking up a diagnostic tool to see if any fault codes pop up. That could give you some extra clues.

Edited January 30 by Niklasbraun

blackout881 · January 30

There doesn't seem to be a single fuse or relay for the fuel pump. If there is, can someone tell me which it is because its not in the manual or on any of the 3 fuse panel diagrams. I have a spot for "second fuel pump" which takes a relay and is empty, but nothing says fuel pump. I find it hard to believe myself, id like to hope I'm stupid but it seems it does not exist in my 2019.

blackout881 · January 30

Just got to scan it and its throwing 16 codes. p1682, p16a7, p16bc, u2084, u0146 u0100, u0101, p0689, p1682, p16a7, p16af, p16bc, p16bd, u0284, u1345.

So now I am thinking something in the battery is going haywire. Might just attempt a new battery and checking the ground cable connection.

Has anyone had this issue???

silveradosid · January 31

sounds like the fuel pump module has failed, it was a problem in 2019. it is above the spare tire. dealer might not have one but you can usually get one on ebay.

2020 fuel pump module update.pdf

blackout881 · February 1

Very hard part to find. Any list of inventory at dealers within 2 hours from my house every one I called it is spoken for. Ordered one on eBay and the seller wrote me a message and said it will take a month or so to get to me, so I had him cancel the order. I do not know what I’d be doing if I didn’t have a second car.

can anyone answer me if this is “plug and play” or if it needs to be programmed to the truck? I’m reading mixed things. Seems like older models need to be programmed, but I read some people with newer models say it’s plug and play.

Anything else anyone can recommend I try while it’s sitting in my driveway? If it were not the module… I tried shifting around through the gears incase it was somehow not fully in park, disconnecting the battery, charging the battery, cleaning terminals. It’s just very upsetting that my first truck I bought new and meticulously maintained and serviced is dead in my driveway at 55k miles. I was in love with GM until this, in 25 years of driving this is the first time I am stranded with semi-quick solution and honestly it’s making me want to sell it and just buy a old diesel with 150k miles for towing. At least when that breaks I wouldn’t be mad lol

blackout881 · February 1

example… my neighbor has the same truck as me.. before I bring over a 12 pack and ask him if I can test his part to ensure it’s what’s wrong with mine, I’d like to know if it’s plug and play. Also do not want to mess up anything with his truck, so don’t even want to ask lol.

silveradosid · February 2

read this post, it is related to your problems

blackout881 · February 5

Here is the outcome.. I would have never found this. Has anyone else had corrosion in this area?

https://app.truvideo.com/v/jPhaCKRS?s=qc2fUg+2+dCFXPz4zRYWefJHv50JVRO0

asilverblazer · February 5

How did you trouble shoot?

blackout881 · February 6

Started with fuses and relays, just basic if they are blown or operating. I wanted to replace the FPCM blind just to throw parts at it but Everything else in the truck was ok electronically. I had a friend that is a tech scan it in my driveway (after I scanned and got 16 codes). He said it’s something to do with the power going into the fuse box after multiple TSB’s showing up. That’s when I brought it to the dealer. They did a great job and documented it in video. I do have to say even though it’s a steep price they did take my entire harness apart and repair multiple wires, and had a 30 year GM vet do it. He promised he sealed it better than factory in that area. I hope so, I really like my GM vehicles now. Recently switched over from ford and dodge. Looks like every brand has their issues.

blackout881 · February 6

My last dodge truck before this, heater core went at 65k miles. I tried flushing it at the dealer, then flushing the core myself with CLR. They wanted about $2800 to replace with taking the dash out. I couldn’t accept that and got rid of it. I guess I can accept a grand for a bad wire I could never find myself. Still sucks.