New 2019 Z06 - Surging at highway speeds
 

Hi all,

New 2019 Z06 owner here. Purchased new LBR Z06 a few weeks ago and so far have about 400 miles on the clock. I thoroughly enjoy driving and cruising in the car and I am certain it will be even better after I hit the 1500 mile mark when I can open it up.

I am new to the Corvette scene, so hopefully I am not asking redundant questions. I did try the search feature but the "surging" keyword did not result in anything helpful

So here it is; was cruising last weekend at 75-80mph on the interstate and noticed the car was surging or felt almost like a studder or misfire while maintaining speed. I did not obtain any CEL lights, but was wondering if anyone else has experienced this behavior? I assumed that it could be a MAF issue or perhaps a bad tank of 93 gas I dumped in? On a car this new I cannot imagine what could be causing such behavior.

Thanks in advance.

A8? Feels like rumble strips?

Correct, A8. It feels like you're slightly on/off throttle or a misfire/stumbling feeling. No rumble strips thankfully. :)

Need a little more information and a little more accurate info. Surging is the engine speeding up....studder or misfire would slow engine down, but studder and misfire would set codes. Where did you buy your gas....you should only be using top tier fuel. There are some things that feel different until you are broken in, I noticed a big delay in shifts during break in but that went away after 500 miles. You can also set you display so you can see if it is going into V4 mode....that may be what you are feeling. I always drive in manual mode so the car does not go into V4 in manual mode, but wait until you are broken in before driving in manual mode all the time. Next time you feel what you feel put it in manual mode and see if it feels better, if you can do it while watching the V8/V4 mode light that would tell you what is happening.

Good way to break down the difference between surging and misfire / studder.

The car felt as though it was being held back or a studder/misfire with no apparent CEL's. I could also hear the motor sound as though it misfired like a hiccup. This condition occurred 4-5 times while cruising at 75-80mph over the course of a minute or two on the interstate, but ceased when I gave the car more throttle to change lanes and got off at the next exit.
At the very least, I will have to keep an eye on things to see if 1) if it was a condition where the car was going between V4/V8 mode and 2) if it continues and at what RPM/speed I am encountering the behavior.
I only run 93 Octane in the car, with the latest gas coming from BP.

Thanks for the input.

I think you were going into V4 mode....it comes right out of it when you hit the gas. It comes on under light constant throttle on flat ground or going down hill. I don't think you are having anything out of the ordinary. If you were not in manual mode, at 75-80 MPH you were in 8th gear...that is also when the Torque converter locks up. Both V4 and TCLU are for better gas mileage. Manual mode gets rid of V4 altogether, so that will not be an issue and when in manual mode I rarely go into 8th gear so the eliminates TCLU. Try it for yourself and see if that is what you felt.

Thanks for the reply. This is very helpful with helping me get used to the car and it's nuances.

i sat outside the dealers showroom before departing on Jun 1 and plugged the RANGE AFM into the port. 710 miles later I can admit I felt some whoosh!, like from 77-100 miles/hour when my foot depressed the pedal to pass weekend rubbernecker traffic on the interstate. but even during the acceleration, the supercharged V8 engine runs like a Rolls-Royce, smooth as silk, none of that turbo rubber-band-tuwang business when the turbo finally spools up and get gone. MB et al have to use 2 turbo's on a motor to eliminate that turbo lag, which seems to me to be an unnecessarily complicated solution when a supercharger solves with just one. I do secretly wish it had the Mel Gibson on/off switch supercharger with visible housing and pulley.) Which is why the V8 is the greatest engine design ever created, shorter than a straight 8 but just as well balanced. it's blasphemy (and bad engineering) to ask it to go out of balance to save a buck on gasoline. 710 miles at interstate speed in a full time V8-on mode with ac on full time netted exactly 22mpg from my gas gals pumped divided by odo miles. The instruments are optimistically reporting avg 25mpg, guess thats to fool the epa guy. city/suburban driving full time v8 now at 1200 miles: 18 mpg. its just a damn shame to pay a $1300 guzzler tax on that when both of my Tundras, 2012 and 2015, only got 15mpg, guzzler tax-free.

My bet is on the V4 mode transition to V8 mode and back. I got use to it and it was much less noticeable after the 500 mile break-in was over and the redline on the tachometer jumped up to 6500. It doesn’t take much of a slight hill to drop it out of V4 mode into V8 mode. It is much more obvious if you ever run in eco mode (which I never do anymore). Stick with that top tier gas and enjoy your ride !!

Put the car into manual mode with the paddles the next time you feel this and see if it goes away. The car will stay out of V4 mode when in manual shift mode. Also, you can change the speedo display are to display the V4/V8 icon which will show when it goes in and out of V4 mode. If the feeling you feel happens with the icon moving in and out of V4 mode then you have your answer as well.