2016 Gt350 lag/hesitation between 2700 and 3000 rpm

[Trackaholic]

That dip on the dyno is a different phenomenon IMO.

I have what I believe the OP is talking about, and it definitely happens below 3000 RPM. It also seems more noticeable at light to medium throttle, rather than full throttle as would be shown on a dyno. I notice the effect also when making subtle changes in throttle position, like when going from slightly accelerating to steady state, the car will hesitate slightly in that RPM range, almost as if one lifted heavily off the throttle, instead of very lightly. Finally, I do think it is less noticeable in sport mode.

IMO, what the OP describes has something to do with the throttle mapping or throttle position, and hence the feeling changes depending on drive mode.

I also have the dip @ 3200 shown on dynos, and I agree that it seems to be related to timing programming, or at least something intentional happening at that point, since the transition occurs over a very narrow rev range.

-T

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[Adriano S.]

makes sense .. confirms my initial thoughts ! thx guys for the answers so far!

 

[snaproll]

Just like a Boss 302 - falls flat and stumbles down low. Interesting that they have this feature in common.

 

[FORDSTANGER]

Yep. I have felt same as Trackaholic explained. Can't really reproduce it either. It is not prevalent during medium or harder acceleration events. It is intermittent at best and at part throttle and gradual throttle movement.

 

[firestarter2]

That dip on the dyno is a different phenomenon IMO.

I have what I believe the OP is talking about, and it definitely happens below 3000 RPM. It also seems more noticeable at light to medium throttle, rather than full throttle as would be shown on a dyno. I notice the effect also when making subtle changes in throttle position, like when going from slightly accelerating to steady state, the car will hesitate slightly in that RPM range, almost as if one lifted heavily off the throttle, instead of very lightly. Finally, I do think it is less noticeable in sport mode.

IMO, what the OP describes has something to do with the throttle mapping or throttle position, and hence the feeling changes depending on drive mode.

I also have the dip @ 3200 shown on dynos, and I agree that it seems to be related to timing programming, or at least something intentional happening at that point, since the transition occurs over a very narrow rev range.

-T

It might be the same dip it might just shift when you are at partial throttle. It is probably throttle related but it feels like the Variable timing changing the cam. Or a jump in the amount of timing advance. All guesses.

 

[Zitrosounds]

I spoke to livernous(Spelling) he said it was the nature of the engine. I havent seen a dyno with out it yet.

It is most definitely the nature of this engine due to its uniqueness. It's most likely a combination effect with the FPC layout, firing order and single throttle body. I don't think eliminating just one will ever get rid. Adding headers seems to improve the dip but does not eliminate it completely. I was doing some post track inspections and noticed that the bank 1 header has EUUGE! flat spot as it cross over the steering shaft. That is a must fix I will get to so enough. I keep shaking this tree in my yard but money has yet to fall.

 

[nastang87xx]

I was doing some post track inspections and noticed that the bank 1 header has EUUGE! flat spot as it cross over the steering shaft. That is a must fix I will get to so enough.

That bend has no where near the pinch to affect power. Trust me. I crunched a header on my previous car to clear a starter and wire and I lost exactly zilcho power or torque.

As tacky as it is, also go check out Engine Masters on Motor Trend and the demolish a set of headers with zero change. And it wasn't a dinky no air requirement engine either. It was a big mother.

 

[Zitrosounds]

That bend has no where near the pinch to affect power. Trust me. I crunched a header on my previous car to clear a starter and wire and I lost exactly zilcho power or torque.

As tacky as it is, also go check out Engine Masters on Motor Trend and the demolish a set of headers with zero change. And it wasn't a dinky no air requirement engine either. It was a big mother.

Thats good to know!!! Thanks!

 

[SilverSerpent]

Sorry, thread necro. Having this issue as well.

Happens between 2000-3500 RPM. Under light - medium throttle during acceleration. The car gets a bit of a hesitation and it feels like the power is cutting in and out. My initial thoughts were something like detonation or other combustion issue (as I had a Subaru that exhibited the same behavior prior to breaking ring lands), traction control kicking in (since I first noticed it in wet conditions) but never saw a light, the A/C compressor suddenly cycling on/off/on or ignition timing related. It's more noticeable when engine is cold-ish but still does it at operating temp. I'm wondering if that cam profile switch over guess is correct.

It feels like there is something wrong. Like a subtle bucking. You'll be accelerating from a stop, smooth throttle operation, then in 2nd & 3rd around 3k RPM you'll feel the power fall off and then come back on once or twice like a switch. Like some kinda weird electronic throttle/engine control bs is acting up.

2,800 miles on the car and I bought it a couple months ago with 1,500. Took it to local dealer for post-purchase inspection (I bought it out of state) and I, like an idiot, didn't even think to mention it as I had just got the car and thought it was the A/C or something weird. They didn't find any issues with the car.

 

[Sagittaria]

Same here. It annoyed me so much that I went and spent the $50 and performed TSB 19-2090 for surging throttle myself on it (didn't want to deal with dealer shenanigans). No effect. Judging on this thread and the number of posts on the fb groups this seems to be pretty prevalent and I'd guess inherent to the OEM setup & tune.

I've read that aftermarket tunes can help with this. Guess I'll find out when I get it tuned for e85.

 

[JAJ]

Try this: https://www.mustang6g.com/forums/th...that-reduces-piston-slap.121326/#post-2532893

 

[drkuster]

Try this: https://www.mustang6g.com/forums/th...that-reduces-piston-slap.121326/#post-2532893

Has anyone installed the ECU update mentioned here and noticed a difference? Just picked up a 2016 GT350 with ~ 2000 miles and notice the lag/hesitation in Sport mode periodically around the same RPM range.

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