Adnimation ATF

Collapse

MECF_728x90_top

Collapse

Announcement

Collapse
1 of 2 < >

Corvette Today Podcast: TONS OF NEWS THIS WEEK

We've been doing Corvette news & headlines podcasts on CORVETTE TODAY since September 2020. I don't remember ever doing a news & headlines podcast with this much critical information packed into one podcast! https://podcasts.adorilabs.com/show/...ppfrkBCyZstwdl. This is a "must listen" to podcast. Here are a few of the topics covered in this episode....

1. Chevrolet confirms the introduction this Fall of the 2023 C8 Z06 with a new video release-and it sounds like a Ferrari
2. Corvette dominates sales in Q2 2021
3. Chevy dealerships have received their first 2022 C8 allocations
4. Callaway looks ahead to 2022 and the Callaway C8 Corvette
5. Right-hand drive C8 is revealed at the Goodwood Festival of Speed in the UK
6. New GT-3 spec C8.R expected in 2024
7. California will start failing cars with tuned ECU’s during smog checks
8. The National Corvette Museum delivers their 14,000th Corvette
9. A couple exchanges wedding vows before taking delivery of their C8 at the NCM
10. "Life in the Fast Lane" by The Eagles is a story of cocaine and a fast Corvette
11. Sigala Designs shows off a completed widebody kit for the C8
See more
See less

First Driveability Issue Surging Engine Stumbling

Collapse
X
 
  • Filter
  • Time
  • Show
Clear All
new posts

  • First Driveability Issue Surging Engine Stumbling

    First very noticeable driveability issue. Vin #3815 - 3000 miles - Never used Launch - Haven't driven hard into high RPM . No engine lights.
    Leaving my garage today 75 degrees outside , after warming engine up for 2 minutes at idle. Driving 25MPH down my street engine surging(like I was varying the throttle). Thought it was strange as it has never done that. Went to local store and picked up a few things and when I came back out after 5 minutes started the car. Windows up and AC on there was an Extreme Gasoline Smell after starting the car for a couple minutes. Then in traffic doing 30-50MPH car started surging again with my foot steady on the throttle. Then stopped at a light the engine was stumbling and stuttering and did this at several lights but not at all lights. Stopped at another store and when leaving the lot again that Extreme Gasoline smell again with windows up and AC on.
    NOTE - I had changed my oil at 2500 miles and there was a EXTREME HEAVY Gasoline Odor. I have always changed oil on my vehicles myself and have never smelled oil with such a strong gasoline smell.
    I have a feeling there is a weak, cracked or broken intake valve spring allowing too much fuel into the engine at the wrong time. My engine also has a very heavy ticking noise till it hits 5th gear just casually cruising around town. ( which I believed was just injector noise ) Now I am thinking a weak, broken or bent intake valve spring. My Vin falls into the category with the valve spring issues.
    Rocket City Florida- 2001 ZO6 - 2013 427 Vert - 2020 Stingray

  • #2
    Definitely getting Extended ...................................Warranty
    [Current Corvette 1999 C5 Z51 Magnetic Red Coupe]
    Depost 6/17/20, Allocation 4/20/21 RedMist 2LT HTC Z51 - TPW-8/2

    Comment


    • #3
      Very, very sorry Frenzy36 to hear of your issue. Going to the dealership very soon?
      GBA Black; HTO Twilight/Tension interior; Z51 & Mag Ride; E60 lift; 5VM visible carbon fiber package; 5ZZ high wing; FA5 interior vis CF; ZZ3 engine appearance; 3LT; Q8T Spectra Gray Tridents; J6N Edge Red Calipers; SNG Edge Red Hashmarks; VQK Splash Guards; RCC Edge Red engine cover; VJR illuminated sill plates. Lifetime, annual contributors, and 23 year members of National Corvette Museum. Home is the beautiful Pacific Northwest.

      Comment


      • #4
        Sorry to hear Frenzy. I just turned 3,500 miles. VIN 5278. I was hoping I had made it past any spring issues (and may have) but seeing your post will now make me have that small doubt in the back of my mind. Please keep us posted on what is determined.
        Torch Red; 2LT; Z51; Two Tone Adrenaline Red GT2 seats TU7/AH2; Mag Ride FE4; Front Lift E60; Engine Appearance ZZ3; Pewter Rims 5DG; Silver Center Caps RXH; Battery Protection ERI; Yellow Calipers J6E; Yellow Seat Belts 3M9

        Comment


        • #5
          Originally posted by John View Post
          Very, very sorry Frenzy36 to hear of your issue. Going to the dealership very soon?
          I will have to call around on Tuesday as the local dealers are not C8 Certified. Would like them to check it out. Possibly it threw a code or two. I was hoping it would be a one and done, but just went for another 20 mile ride and no surging this time , but stumbling is very obvious at red lights, but not consistent. I'm am going to give it the benefit of the doubt and run the fuel out of it and fill up with a higher octane fuel from a different station. I am crossing my fingers that it is hopefully just a fuel issue. I would probably be over the car if it turns out to be a valve spring issue. ( I know me) . I might also open it up a bit on a deserted road as I have been doing most of the last 1000 miles city driving in some pretty heavy traffic at times. Will post back to this thread as to the outcome.

          I was remembering a post where there were some kind of maxi-pad looking gizmo's inside the air intake that were coming lose. Tried to find it but don't know what to search for. Does anyone remember that?
          Last edited by Frenzy36; 04-04-2021, 12:27 AM.
          Rocket City Florida- 2001 ZO6 - 2013 427 Vert - 2020 Stingray

          Comment


          • #6
            This is disappointing, you would think GM would put better valves springs in Corvette?
            Last edited by pageda; 04-04-2021, 07:00 AM.

            Comment


            • #7
              Sorry to hear about your issue. Since you have been smelling gasoline since your oil change, I'm thinking your issue may be a fuel line leak and not a broken valve spring. You have put 500 miles on the car since then. More likely a fuel leak than a broken valve spring. They all tick a bit.
              Hopefully you find a qualified tech to sort it out.

              Comment


              • #8
                Frenzy36 I agree with capevettes.

                If it was a mechanical issue such as a valve spring, it would be a constant problem, not an intermittent one.

                And you wouldn't have the gasoline smell.

                Did anyone service the top of the engine cover/assembly, such as installing the extra DCT fluid?

                If it were a fuel line or fitting leak, that is also a mechanical issue of course. But that could be an intermittent issue, because jostling a fuel line fitting from bumps could cause it to leak, and the next bump might cause it to align correctly and not leak and not surge.

                Just educated guessing here, of course.
                Last edited by Shepherd777; 04-04-2021, 06:54 AM.
                Bob Sliwa
                "I was cruising in my Stingray, late one night, when a Tesla Model S, pulled up on the right......."
                Currently Building an All-Electric,1963 Split-Window Coupe Ludicrous Speed Restomod.
                Ludicrous Speed - https://youtu.be/ygE01sOhzz0

                2020 C8 ELB - Event Status 666 - Completely destroyed at the race track due to year 2020! Insured!!!
                2022-2023? E-Ray - Number 4 on the List at MacMulkin!

                Comment


                • #9
                  This does not sound at all like valve springs but rather something related to fuel delivery such as the injectors etc. Perhaps a faulty injector staying open to long. The gasoline smell may be related to unburned fuel from incorrect injector timing. Hopefully its nothing more than that

                  Comment


                  • #10

                    Nov. 2020:
                    Just limped home in VIN 3688, check engine light, rough running, "Service ESC" and "Service Traction Control" showing. After turning off engine smelled "burnt" and passenger side intake fan ran for a long time. 895 miles showing.

                    Update:
                    Dealership says it's not a broken valve spring and they can't replicate the problem. They're talking to GM about the codes being displayed. I'll go to the dealership on Monday to get a better understanding of what is/is not happening. I seriously felt the symptoms I was having matched what others were getting with a broken valve spring.
                    .

                    Update: 12.2.2020, the dealership apologized for bungled communication, GM has authorized replacing all valve springs.
                    .

                    Final Update: 12-5-2020: the dealership and GM Tech diagnosed my problem as a "faulty fuel injector," TAC suggested a compression test and a leak down test. Results within normal specs. All valve springs were inspected with no issues found. #5 injector was replaced and GM authorized all sixteen valve springs be replaced for "customer satisfaction." Car number 3688 did not have a broken valve spring...but, the customer (me) is satisfied. Thank you Integrity Chevrolet and GM.



                    March 26, 2021
                    Car #3688 back in the shop with same symptoms, check engine light, "stumbling" rough running, "Service ESC" and "Service Traction Control" showing. After turning off engine smelled "burnt" and side intake fans ran for a long time. (my dealer Tech did mention that Service ESC and Service Traction Control codes display for many different engine issues).

                    This has happened at 25mph, 43mph and 55mph. I usually drive in Sport mode, but tried all modes on way back home. Seemed to occur in all drive modes. I may have been mistaken, but, I felt that when I held the shift paddles in neutral mode and revved the engine it didn't miss...not 100% sure of this. I've never done a hard launch...but, have "floored" it a few times on long stretches.

                    Been in for a week with no progress, the one mechanic I really trust has two Corvettes (not C8s) ahead of me. I'll update with status when fixed.

                    April 12, 2021
                    Leaking fuel injector on cylinder #3, fouled spark plug, #3. Replaced both.
                    This was my second fuel injector problem.
                    Last edited by DanVette; 04-14-2021, 08:22 AM.
                    U.S. Navy(Ret); past associate editor of Vette Vues Magazine; Founder-Corvette Chattanooga; Founder-National El Camino Owner's Assn., NCM(L).
                    2020 Coupe, ELB, 2LT, performance exhausts

                    Comment


                    • #11
                      Originally posted by Frenzy36 View Post

                      I was remembering a post where there were some kind of maxi-pad looking gizmo's inside the air intake that were coming lose. Tried to find it but don't know what to search for. Does anyone remember that?
                      C8 - HydroCarbon Pads still falling off causing LT2 engine problems - MidEngineCorvetteForum.com
                      1LT |Torch Red/Black | MSRP $59,995 | DOB=8/31 | Home on 9/24.
                      Splash Guards, Cargo Nets, All weather Jake Floor Mats and Cargo Area Liner, and Front Grille Screens behind grilles.

                      Comment


                      • #12
                        Originally posted by Frenzy36 View Post
                        First very noticeable driveability issue. Vin #3815 - 3000 miles - Never used Launch - Haven't driven hard into high RPM . No engine lights.
                        Leaving my garage today 75 degrees outside , after warming engine up for 2 minutes at idle. Driving 25MPH down my street engine surging(like I was varying the throttle).
                        When I take my car out, I'll take the "long way" through my subdivision and an adjacent subdivision to let my fluids get up to temp before opening-up the engine on my favorite roads.

                        During this warm-up, I'm typically in tour mode, and the engine switches between V4 and V8. I can feel some surging as the V4 to V8 transition occurs, at speeds around 25MPH. I don't consider this abnormal. This is the only time I notice the V4 to V8 transition, when the car is cold. I drive in Track Mode 95% of the time (V8 always on) so V4 transition doesn't occur.

                        I wonder if this is part of what you're experiencing?

                        As for the gasoline smell, the only time I've ever noticed that is after a fill-up, where the pump might not shut-off quickly enough, causing a small amount of gasoline to be captured in the overfill area of the filler neck.

                        I also change my own oil, and didn't notice any gasoline smell when I changed the oil at 500 miles.

                        It does sound like you have some kind of a fuel-delivery issue, and it is odd that the engine is not producing a CEL.
                        Last edited by Mobius; 04-04-2021, 08:49 AM.
                        My C8:
                        '20 Elkhart Lake Blue 2LT Coupe, Natural Interior, GT2 Two-Tone Seats, Performance Exhaust, Front Lift, Carbon Flash Wheels, Engine Appearance Package 2000 Status December 27, 2019; 3000 Status January 2, 2020; 3400 Status March 10, 2020;TPW March 16, 2020; Built June 4th, 2020 (COVID-19); Delivery July 1, 2020

                        Current Vettes:
                        '68 Lemans Blue 327/350 Convertible
                        '91 Turquoise Convertible with Hardtop
                        '14 Lime Rock Green 2LT Convertible, Black Top, Kalahari, 7-Speed, Performance Exhaust

                        Comment


                        • #13
                          Originally posted by DGinLZ View Post
                          This does not sound at all like valve springs but rather something related to fuel delivery such as the injectors etc. Perhaps a faulty injector staying open to long. The gasoline smell may be related to unburned fuel from incorrect injector timing. Hopefully its nothing more than that
                          Injectors could very well be the issue as intermittent also stumbling while at a light sometimes and sometimes not.
                          Rocket City Florida- 2001 ZO6 - 2013 427 Vert - 2020 Stingray

                          Comment


                          • #14
                            https://www.thecorvettemechanic.com/...4596#post24596




                            Might want to post up description of symptoms?

                            Comment


                            • #15
                              injectors bro

                              Comment

                              MECF_728x90_bottom

                              Collapse
                              Working...
                              X