Was Driving my 16 S on a rally today when halfway into the drive on the highway as I go to pass someone and downshift and step on it the car barely moves, like 1mph every second, Could barely get to 80, So I pulled over on the shoulder, turned it off and an on, As I try to merge onto the freeway I floored it from a dead stop, and I **** you not the car took a good 10-12 seconds to get to 60mph. I know something is very wrong but It threw 0 codes, shifts fine, runs fine, just feels like it has a 100hp, and when in manual mode sounds very week at 6k, like it is dying out,or out of breath so to speak, Don't think its fuel as Its the same station I always use, 93 ofc, and I had already ran through half a tank with no issue.

The only thing that really stands out is that I can not hear any supercharger whine, it was never very loud but at full throttle or revving with the hood open you could always hear it pretty cleary, and now nothing. That leads me to think that the car is not making any boost, and just running N/A, but I do not understand how it is not throwing any codes at all, dropped if off at the local dealer and will hopefully hear back soon. Just wondering if anyone has any thoughts on what it may be. My only other guess is fuel related, but the fuel pump was replaced less than a year ago, car has 34k miles on it. Bone stock as well. Thanks and hope everyone had a good thanksgiving! stay safe and healthy.

this is full throttle in dynamic mode-

 

just chiming in that driving looks very similar to the time I shredded my supercharger belt after I got my VAP stuff done. Pretty much was running without the supercharger while I slowly made it into a preschool Parking lot which seemed like it took forever also same thing whine went away.

 

When I had something similar it turned out to be the electrical connector on the fuel pump not being fully seated and had worked loose, resulting in intermittent connectivity. Mine threw a CEL for fuel pressure errors, though. Good luck finding the cause!

 

did it throw a check engine light when that happened? the one exposed Belt I can see from the engine bay with the cover removed looked in perfect shape, but I could have been looking at the wrong belt. the car ran perfect, besides the lack of power, I mean slowly but surely I was able to accelerate into high numbers, just took me prob a minute of full throttle to get there. Was it a quick fix?

 

Sounds like limp mode. If you don't see anything obvious when looking into the engine bay, pull the ECU codes and see what's stored.

 

The thing is the car has no codes, and with limp mode it normally doesn't let you in dynamic or rev above a certain RPM, this lets me do everything like normal, just feels like its down 200 horsepower.

 

You pulled the codes or you don't have a CEL on?

 

His first post did say "but I do not understand how it is not throwing any codes at all".

 

No cel, and i used my code reader and it did not show any stored codes.

 

A lot people believe when a CEL isn't on, the car isn't throwing codes. They don't understand that not every code triggers a CEL. I never "assume" someone knows this.

Typically if there is no cell, then in my experience it's a mechanical issue. I haven't had a similar problem with the F-Type, but in my other FI cars it's been something with the FI system (whether it's a failed sc or turbo, or belt slipping, damaged coupler, etc). It would also help to have a video without the music banging to see if there are any unusual sounds coming from the engine area when trying to accelerate.

 

Floor mat stuck under the accelerator? Crushed exhaust pipe?

 

that was the only video I had but it sounded normal, besides maybe a little out of breath sounding at the top. I'm guessings its mechanical as well, but should hopefully know soon if the dealer ever returns my calls.

 

I wish lol, that would be an easy fix haha, but no even when you use the kick down pedal, it kicks down like normal just barely moves lol. is this how p300 owners feel everytime they get in the car? lol Jk jk jk, but ya very odd.

 

You were pretty much right, the pulley froze and somehow the belt slipped and damaged the tensioner, some bs they told me, they had to replace 2 belts and pulley/tensioner they told me

 

I guess you now know what a naturally aspirated version would feel like ;^)

 

Yes, awful. I mean I had a 2014 nissan sentra with a CVT and that felt quicker

 

Without the supercharger, the car probably went in to a sort of safe mode which had enough power to drive at highway speeds but not much more. I'm sure there's no on the fly N/A tune, lol.

 

I thought that it would have gone into limp mode, it was letting me rev all the way up to 6800, so idk, but i agree with the no on the fly N/A tune. thats why it was so slow with no boost, my guess is the blower adds 80-100 horsepower, and it def didn't feel like a 280-300 horse car.

 

My suspicion is that while the blower adds power when it's working, it actually subtracts power from the N/A level when the belt breaks. It's not just not helping, but is in the way.

 

I'm not suggesting this was happening with your car, but it depends on the car and what they do for their own limp mode. Some cars it does reduce rpms. Some, it reduces how quickly the car can accelerate but doesn't limit the rpms (like reducing the timing). One my my wife's previous Audi's, it was the latter. The rpms were not limited in limp mode but it took 20x as long to accelerate to a pace that wouldn't get you crashed into from behind (and it was a similar, a FI car with a mechanical problem issue to the FI system so no CEL).