Most do not have this issue. Also, TPS will spike up to around 90% when the SC clutch engages from what I have logged.

 

Glad this thread got figured out

 

I don't think this actually has been figured out other than we know it's the throttle body opening just about max for a split second before returning to nml that cause this, which seems to be fixed with a "new tune" but whats in the tune to be causing this?

 

I keep it in comfort mode 90% of the time, No issues. It only hiccups once in awhile in sport mode and only at very slow speeds.

 

same here... ive had my 06 e55 for 2 years now exactly..and it always did this.... my car had an EC tune and a crank pully when I bought it.... after 6 months i called Ec and was told this was "normal" because of the tune....but 2 yrs now and im getting tired of it as well..and like another posted, try to avoid spirited driving with others in car since they think somethings amiss..would love to at least ilmit the issue

 

Me too. When I was running a stock pulley, tune, and TB I would get a *slight* hiccup that went along with the "chirp" when the SC engaged.

Now that I have a Lawshee tune, 77mm pulley, and 82mm TB I get the severe "buck" or "hiccup" right around 1900 RPM when driving under partial throttle.

 

I have been able to trigger the hiccup at ~80 mph in 5th, 4th, and 3rd gear. It used to happen like clockwork at a certain point in my commute (highway, going from flat to uphill), so I tried to figure out a way around it. As my testing confirmed, it was not dependent on RPM.

I used my data logger to try to figure it out and all I could manage to find is that it would trigger when calculated load increased while TPS remained constant.

I've had the hiccup happen with multiple tunes from FOUR different tuners, three different throttle bodies (two 82mm and the 90mm), three different versions of the MAP sensor, two different intakes, two superchargers, and even two different engines. I've been through the engine bay with a metaphorical microscope to eradicate leaks and everything looks good.

Switching from the 82mm to the 90mm changed nothing about how and when it is triggered. The only thing that may have affected when it happens is temperature and elevation. Doing A/B comparisons is kinda hard, though. I used to live at/near sea level, now I'm closer to 4,000 ft.

I can "drive around" the hiccup by slightly and constantly varying the throttle while cruising (especially up an incline), but this is such a pain in the b-hole and prevents the use of cruise control if you don't want the hiccup.

I am 99.9% convinced that this is a software-related issue. There is probably some obscure table in the code that triggers a soft limp mode when the Torque:TPS ratio reaches some arbitrary amount, or something like that. I lack the ability to read the ECU, so I can't even begin to test this theory out. The first person to figure out the fix is getting a case of beer from me, though.

 

You hit the nail on the head Denroll. Especially the part about it happening up slight inclines and learning to "drive around" it.

 

Can you go back to stock tuning? It shouldn't happen then, unless your car is modified beyond what the stock ECU settings can operate.

 

I find it amazing that the people that design and sell the tunes have not joined the thread to provide some insight. My car was tuned by Renntech in 2006 and has always had the slight hiccup problem. It seems nothing much has been improved or changed since then. Kind of sad really.

 

Exactly. Everyone (tuners) seems to be regurgitating the same **** over and over. Why else would the same stuff be happen in between tunes for our caped crusader Denroll? He has proven, Imperically that it's somewhere in the ecu and it's not touched by a tune.

Has anyone stayed with 80mm or below and still had the hiccup?

 

I went to a 80mm TB and my hiccup went away.
I personally think it's a correlation between the bypass valve and the TB not being in sync. its a airflow timing thing between the two. Think about it the bypass is try to bleed off or maintain vacuum and can not compensate for the increased volume of air. In stock trim if the TB tune or aggressive tune isn't correct you will have the same effect if there is a slight leak leak on a stock TB the same thing will happen as well.
I think the closing of the TB is it trying to recalibrate like at start up because values are off so it closes and reopens to check values.
I might be wrong but from what i have tested that seems to be the case.

 

Interesting theory. I wonder if something as simple as a stiffer or weaker spring in the bypass valve could be the difference.

 

It is something within some ecus because some cars will take the tune and be fine while the same tune on a diff ecu will have the lean hiccup issue.

A tuner would basically have to decipher every table to find the issue, and yes going back to a smaller tb will solve the issue

 

If it helps, I have a Kleemann tune and no issues here.. Very smooth.

 

A good friend had the issue and an old RT tuner fixed it or it never came back lol
He is retired for the most part but his initials are J.K for those who know him

 

Ok guys im confused... About which kind of "hiccup" is the OP complaining about? Is it "Super-Lean mode" hiccup, mostly happening with 82mm or 90mm TB, that you have to cycle your ke to get rid of it and that could kill your engine as it runs super-lean as soon as it occures?
Or is it another kind of "hesitation" that sometimes comes with mild acceleration?

 

I'm talking about the super lean mode and so is denroll

 

Denroll,

It is the altitude compensator along with many of of the other posts in here.

Does everyone with this issue give the ECU a cold reset and give the car a strong workout after the reset.
Adaptive strategy in these systems automatically rethinks fuel mileage.
Hence if you are not in performance mode The ECU saves MPG. When you wish to surf the white lines in the road. The ECU map is sleeping.

Eurocharged is tuning around this with fixed pulley configuration and most are reporting success. There are some firmware sticky ECU but if you know how to drive and re-create the problem, chances are we need to drive differently.
Most of the hiccup I believe is coming from adaptive strategy confronting the Boost bypass valve.
Driving attributes and an ECU that makes decisions for MPG have nothing but bad results in a high performance E55.

My 2 Cents, Gator

 

This might be a dumb question.. Can the entire ecu programming be copied from a car that doesn't have the issue, to overwrite one that does?

 

I do not believe the OP means the same...:

 

I agree don't think it's the lean one.. This is different.

 

I know that this thread is dreadfully old. The problem is even older, but I'm still having it. In my case, I have an M113K in a Crossfire. Being a much lighter car than a W211, the hiccup (which is so much more than a hiccup!) is downright violent. The Crossfire has had this issue for a few years, now, and in that time many things have been tried. Lots of parts thrown at the problem, tunes, and time. The car itself is constantly evolving, and in the time since the hiccup arrived, it has had an engine replaced, a different supercharger (new bearings, different snout, silencer slots welded, etc), different pulley setup (83mm upper to 180mm lower/stock upper), each and every sensor replaced, wiring checked many times over, two sets of injectors, several different throttle bodies (stock and 82mm), brand new bypass valve, alternator (to rule out electrical noise), and quite a bit more. Later I designed a brand new set of CAN data logging tools, and was able to capture the moment a hiccup happens in the attached graphic (see the almost square dropout in the 4 torque graphs?).


Here's what I know for sure:
1. It's not a mechanical issue
2. There are no air leaks (checked with a pressurized smoke machine)
3. No wiring faults or voltage supply drop outs
4. Fuel pressure is steady
5. Throttle body independent (stock and 82mm both do it)
6. Not boost dependent (happens in vacuum, not boost)
7. Is not supercharger clutch engagement (more on this below)
8. Is not temperature dependent
9. Is repeatable, and coincident with the timing of supercharger clutch engagement
10. Tunes that keep the supercharger engaged 100% of the time do not exhibit the hiccup

So many think it is supercharger clutch engagement, as did I, until I ran this simple test. Using a spare clutch magnet, I unplugged the clutch, and plugged it into the spare magnet. Securing the magnet under the hood, I went for a ride, and sure enough, the hiccup is there, and just as bad as ever! Some have suggested that it is the throttle body or bypass valve doing something, and it sure could be. The onboard data reporting is far too slow to show it, though.

Before I try more, I wanted to reach out here to the ones who have been in these cars the longest. What is the no-kidding solution? Yes, I see go to this tuner or that tuner, but I am wanting technical details. What in the tune is actually causing the issue? Is it a torque limit being exceeded? Is it a diagnostic failure? Someone here knows, and I am hoping that these cars are now old enough that someone can share a practical solution or information on how to achieve one, without fear of loss of profit. Thanks!

 

I may have missed this but have you discussed just removing the clutch and running clutch-less?

 

I have not, but I have run tunes where the clutch is 100% engaged. This is OK, except that this SC sounds like a cement mixer full of gravel at idle, and it is generally not too efficient to be spinning it while running down the highway with the cruise on. In other words, would like the clutch portion to operate as intended, sans hiccup.