ESS S/C Deceleration issue...

[81bear]

Been having some issues with my bypass valve for my ESS 625 kit equipped M3. I've posted a video below and in it you'll see the car cruise along at about 2k rpm and I just let off the throttle a few times. What seems to be off for me is the time it takes for the needle, on the speedometer, to move once I release the gas. It seems like it just stays stationary for a second or so and then slowly starts to descend.

Edit: I just wanted to say that I don't remember it performing link this prior to an incident that occurred a few weeks back where I was accelerating and my rpm gauge seemed to get stuck at 7k rpm then I heard a pop followed by a fluttering sound (I assume the bypass valve). I had my car inspected and my relatively new (a month old) bypass valve was no longer holding boost. It has since been replaced with a stronger blowoff valve but I'm still experiencing the same delay.

I just want feedback from other ESS equipped owners on whether their kits perform similarly?

Another video of an ESS equipped car below. Notice how once he releases the throttle the needle drops rapidly...

[JEllis]

Not really an apples to apples comparison since that dude is letting off at 140 and prior to that he down shifting manually.

I don't have DCT but with my 6MT I noticed off throttle was not exactly the same as my OE 240E software. But then, I would not really expect it to be.

[81bear]

Originally Posted by JEllis

Not really an apples to apples comparison since that dude is letting off at 140 and prior to that he down shifting manually.

I don't have DCT but with my 6MT I noticed off throttle was not exactly the same as my OE 240E software. But then, I would not really expect it to be.

Good point and definitely a bad comparison on my part. But you probably wouldn't be surprised that when search youtube for ess s/c acceleration video's they're all of speeds well beyond what I have in my video so kinda tough to find one to compare. lol!

I guess I'm just wondering if others are experiencing/noticing a similar delay when letting off the gas at normal cruising pace/daily driving situations. i.e. letting off the gas to avoid catching up to the car ahead.

[R_lara]

I don't really see the issue... Does it make u feel unsafe. Remember that charger and weight to the rolling of the engine (more inertia) so i would expect this to be normal, I will pay some attention to this matter tomorrow and see if mine behave like yours.

[81bear]

Originally Posted by R_lara

I don't really see the issue... Does it make u feel unsafe. Remember that charger and weight to the rolling of the engine (more inertia) so i would expect this to be normal, I will pay some attention to this matter tomorrow and see if mine behave like yours.

Any first hand feedback would be greatly appreciated!

No not really unsafe... I've had to change my driving style, using my brake more to slow down rather than just releasing the gas. Other than that there's no real safety issue...

I just want to know if others are experiencing the same thing? Prior to the incident (first post) with the bypass valve I never had this issue with deceleration...

I don't think it's caused by inertia. We think it's caused by having a single bypass valve that can't dump boost fast enough in certain situations. In essence, residual boost after you release the throttle. This reasoning makes sense but again, this is a new experience for me, and I'm look for confirmation from fellow ESS S/C owners that it's normal for a well functioning kit?

[R_lara]

Paid attention to this today it it decelerates just the same as yours did it in seventh gear 2,300 RPM at a leveled street. Will try to make a video on my drive back.

[81bear]

Thanks for reporting back!

[Pro-AM3]

Ive heard about this issue from several people. They claimed it was even worse when WOT and the car continued to accelerate after releasing the pedal.

I vaguely recall one person having the issue and then claiming to resolve it with a new BOV, as thats my theory as well. That the BOV's are not up to task. I dont know anymore about it, but I do know your not the first to complain about it

[81bear]

Originally Posted by BossManE90

Ive heard about this issue from several people. They claimed it was even worse when WOT and the car continued to accelerate after releasing the pedal.

I vaguely recall one person having the issue and then claiming to resolve it with a new BOV, as thats my theory as well. That the BOV's are not up to task. I dont know anymore about it, but I do know your not the first to complain about it

It seems to be better at higher speeds actually... Now I do have a true BOV not a bypass valve which is what comes standard with the kit... Not sure if that makes much of a difference in this respect... One thing the BOV does do is help me gauge when and how much air is being released as you can hear the valve purge...