Check engine misfire/fuel pump module

SierraNoob · June 13, 2020

I have a 2020 gmc sierra sle 5.3, I bought it may 13th. Starting at about 800 miles check engine light would flash for a minute or two and then go off, this occured every 300 miles until I got in one day around 1500 or 1600. Check engine light stayed on. Called the dealership and took it in was throwing misfire codes, the diagnosed it as fuel pump module reset the codes and ordered the part and sent me on my way. Come back in and had it replaced when the part arrived, well now fast forward to a tank and a half later and now the check engine light is on for the evap system/gas cap, and fuel pressure at 2200 miles. Right at a week from the time it come out of the shop. I've been extremely happy with the truck but I can't believe I'm going to have to find time to get it in the shop to be looked at and fixed again. I'm at wits end already. Anyone else having these issues?

Edited June 13, 2020 by SierraNoob
Not enough info in topic

SierraNoob · June 22, 2020

Well issue the second time was supposedly the purge solenoid, it was replaced.

Half a tank of gas later at 2900 miles misfire code again and now at 3000 miles the check engine light is on solid.

3 times in 3 weeks, misfire codes every single time and evap system issues.

SierraNoob · July 2, 2020

3rd Time was the filler neck, it had a crack

Less than 200 miles later check engine for misfire again, code not present when taken to dealership, they've opened a case with gm and I have a claim open waiting on response.

4 times in 4 weeks.

SierraNoob · July 24, 2020

Took back to dealership after another misfire. Tried to replicate for a week. They put a 150 miles on my truck. Got it back and over the weekend it happened again. Took it back monday and now they are waiting on lifters and a dfm solenoid at 4100 miles and I've been in a loaner for almost 2 weeks. This has been the worst experience ever. Dealership has been awesome but gmc hasn't been that great.

Shiva · July 24, 2020

That sucks man. Sorry to hear that. I have a 2020 Sierra as well. Nothing but issues every week. My dealer sucks though. They put scratches and keep breaking the plastic parts every time they go in. Most of the time they won't do anything but reset the code tell me it's normal and send me back home.

Curious. What was your build date and assembly location?

Built Feb 2020 in Mexico

x31 · August 29, 2020

I got here searching this issue. Having the same on my issues with my 2020 Sierra 1500. Built in Mexico. Bought early March. Problem just started last week at 5500 miles. Dealer checked for evap leaks then reset it the first time no trouble found. Second time it came on they changed the purge solenoid and said that a spider had made a home in the vicinity of the purge solenoid?? They did not mention misfiring either time but I am feeling what I think are misfire vibrations coming through the steering wheel and the fuel mileage has dropped as well. Set an oppointment for me Monday. Not good. This is my work service truck and I can't have this carry on much longer. Hope they figure it out soon or it is gone.

x31 · August 29, 2020

I have the paperwork now. Just wanted to add the code. My code was p0455 evap leak. We'll see what happens Monday

SierraNoob · September 8, 2020

I've had issues with purge solenoid, fuel pump, filler neck, and I've had dfm solenoid #3 replaced, all my lifters, and after 2400 miles I'm at 6600 and the check engine has been on for 3 days for emissions and I've been having the check engine flashing for misfires during the time period. It was off this morning but I'm taking it to the dealership today. Had it since may 14th and this will make the 9th or 10th time in the shop. It's only been in my possession about a total of 3 or 4 consecutive weeks this last time. Before that it was in the shop every single week since the week after I bought it

Shiva · September 8, 2020

5 hours ago, SierraNoob said:

I've had issues with purge solenoid, fuel pump, filler neck, and I've had dfm solenoid #3 replaced, all my lifters, and after 2400 miles I'm at 6600 and the check engine has been on for 3 days for emissions and I've been having the check engine flashing for misfires during the time period. It was off this morning but I'm taking it to the dealership today. Had it since may 14th and this will make the 9th or 10th time in the shop. It's only been in my possession about a total of 3 or 4 consecutive weeks this last time. Before that it was in the shop every single week since the week after I bought it

Now might be the time to ask GM to do a buyback.

SierraNoob · September 8, 2020

I was literally supposed to come to terms on some kind of reparation for all the stuff that has happened today. That's has now changed. I've been in contact and have had a claim with them since the 2nd week of ownership. Now I'm gonna be asking for a buy back no matter what happens. The truck has been proven to be unreliable time and time again. Something tells me im about to fight with them

YourDailyBeast · September 8, 2020

27 minutes ago, SierraNoob said:

I was literally supposed to come to terms on some kind of reparation for all the stuff that has happened today. That's has now changed. I've been in contact and have had a claim with them since the 2nd week of ownership. Now I'm gonna be asking for a buy back no matter what happens. The truck has been proven to be unreliable time and time again. Something tells me im about to fight with them

That's some sobering news, I hope you resolve your issues and spend your hard earned money on something that actually works.

SierraNoob · September 8, 2020

Dealer has my truck and is getting with gm on instructions on diagnosing and repair, which is what they have done the past few times because it seems to be a technical gremlin.

I also contacted my service advisor at gm and they are gonna start paper work for either a buy back or trade in, from what I can tell gm isn't too great about buy back prices even though I got mine on sale. I'm also concerned I won't be able to get another one like it for the price I bought it.

Shiva · September 8, 2020

1 hour ago, SierraNoob said:

Dealer has my truck and is getting with gm on instructions on diagnosing and repair, which is what they have done the past few times because it seems to be a technical gremlin.

I also contacted my service advisor at gm and they are gonna start paper work for either a buy back or trade in, from what I can tell gm isn't too great about buy back prices even though I got mine on sale. I'm also concerned I won't be able to get another one like it for the price I bought it.

Depending on what they offer you for trade/buyback it might be better to see what another dealer might offer you as trade-in value for a Ford/Ram or another GM.

SierraNoob · September 8, 2020

That's the problem, I've only made 3 payments on it so whatever they offer me is going to put me in the red. I just want a new truck that's exactly the same. I love the sierra other than the engine I've got

Tahoe02 · September 9, 2020

Lemon law. Check your state for lemon law requirements and then Google search for Lemon Law attorneys who will normally do so with no up front money. They get paid from the manufacturer at the end of the case. I tried working with their trade assistance and that was a joke and so is GM customer no service. Documentation on your part is key. I got all my money back plus GM accessories that I had purchased minus a small fee for mileage. Good luck.