LandCruzer94

For those who don't have a wideband, I was curious and set a threshold alarm in Torque on both short term fuel trims at 22.5% to let me know if I'm ever in hiccup mode. Normally I never see trims above +/-15% so it's an easy and quick way to identity if something is wrong. Sure enough this morning, after a week of running perfectly, the alarm tripped after a few minutes of leaving the house and I had a pending 0106 code. No codes last night when I parked it.

210lvr

Here is something that I've been thinking about. There are guys with this issue and guys without.

Since ive had my EC tune I've always had this weird delay in boost feeling when I'm cruising on the highway and give the car just enough gas to downshift. The car revs up makes nose and starts to pull forward but not much, about a half second later there is a surge of power and the car takes off as it should. If I got WOT it will not happen it has to be a light cruise.

Some posters have mentioned that they believe this is an issue with the bypass valve timing. I have not checked yet to confirm that my delay in power is slow actuation of the bypass flap but need to do so. I know of another person that has my same issue.

a lot of people say this issue happens to them when they just barley feed throttle which seems to correlate with my possible bypass flap closing timing issue. I wonder if the ME says "ok close bypass flap, actuate sc clutch, confirm boost parameters....oh I'm expecting X boost but I'm seeing much less and I know the bypass flap is ok because I have no electrical fault, limp home" and this is exasperated by the 82mm tb.

Just fishing here but can anyone that has an 82mm tb also tell me if they have this weird delayed boost feeling when lightly cruising and accelerating JUST enough to get the car to downshift like when you're going to pass a slower driver?

people are suspecting the bypass flap timing and some of the symptoms sure match up. Does anyone know if EC will attempt to correct this? Or is there a tuner that would be willing to give this a shot for diagnosing this finally?

StarvingArtist

The hiccup poll thread seems to have an explanation of the problem. It kinda killed the discussion for some reason.

sexyxe

I have a similar feeling, but more from a stand still. Once moving and about 20mph with the pedal stationary watching the timing it stays around idle values of -10, then they will drop to -20ish with no other changes, then the car really picks up as though it is making boost, but I will still be in vacuum.

LandCruzer94

I'm starting to notice a pattern with my specific hiccup mode that may loop back to the original hypothesis of this thread. Since I've been monitoring fuel trims daily, I can identify within seconds when my car hits hiccup mode and it's practically as I'm leaving my driveway in the morning for work. Drives no different than normal, so I imagine the other guys who have commented that they notice issues about 20 mins into driving are in the same situation and the car only starts showing obvious symptoms at that point.

So what would cause it to happen literally overnight after driving perfect? After driving my car for over a week with zero issues on a new MAP sensor the day it happens is on a very rainy/moist day. The next time it happens 4-5 days later, another rainy/moist day. I'm starting to believe it could be some sort of link to what the pressure sensor on the ECU reads and what information gets passed along (relating to the wild atmospheric pressure differences between when I last drove it and when I went to start it next). Sure, I'm onboard with the fact that it's also related to the tune and potentially backup maps that are untouched, but what would make the ECU start referencing a backup map in the first place?

If an ECU is measuring atmospheric pressure (Ambient, not manifold pressure) on its own too to make adjustments, then that could be related.

LandCruzer94

Just coming in to rant...This s h i t is driving me bananas.
Happened twice in a row yesterday in the same trip after a restart and another time a little later in the day. It didn't happen the way I was previously describing it, it was on the freeway and the feel was a "bump" exactly like a torque converter unlocking but very harsh. Had my parents in the car and it was a pain trying to explain it to them.

Im just frustrated that it went from fine to this so quickly. Today is a new day I guess...

trabots

My E55 with just an 83mm pulley and EC tune has a hiccup on light throttle tip in or where the shift occurs but then with no change in throttle position it seems to delay applying that same throttle position for a good part of a second. Same with my SL55 with 82mm TB and stage 3 mods but issue is worse.

Roverron

Call klemman or renntech ask how many of their cars have this issue.

carguyshu

the factory torque limiters for the transmission cause the car to roll off the throttle during shifts.

LandCruzer94

I've been researching this morning the possibility of going to an 80mm TB while this gets worked out. Since I have a ported 2007 SL55 snout with the different bolt pattern, going back to stock isn't really feasible. My bolt pattern was never modified to fit the 82, does anybody know if the 80mm from the 600 series cars will fit? Was thinking of 2751410625. The SL55 part 1131410625 seems impossible to find used.

Edit: Of course I find the answer after I post and it sounds like it will be a direct fit, just have to swap the pins which isn't an issue.

The question now is, does anybody have hiccup issues with the 80mm TB? Lol

Roverron

80 mm will solve this issue!
It is what i did and for the little gain going to an 82mm or larger its not worth it. If you want larger port the 80mm for flow.
I bought mine from Shardul it's off an S600.

Ł C43 Ł AMG Ł

I know its an old thread.......but dont seem to be getting the hiccup after installing all the sonnax and transgo valve body upgrade parts,its definitely shifting faster with less delay and more positive engagement,,,,,,,,,,, will keep monitoring the situation as I am struggling to resolve an evap issue first before moving onto the TB

lost27

Bumping this thread so I don't lose the conversation about the backup maps and also to see if anyone has had any new luck in solving this issue/

At this point I'm on my 3rd (used) 82mm throttle body and 3rd tune. The latest tune was great over the summer but now with the cooler temps I'm able to reproduce the issue on almost every single drive. It is easiest to trigger by cruising in the 85-90 mph range with throttle around 16-19% (via torque app). After some time there will be a little hiccup almost like a slight throttle blip and the STFTs go well north of 20. It has been hit or miss if it then causes the lumpy idle. If the hiccup happens twice in a row (on two drive cycles) it triggers the P0106 code.

I've also noticed that throttle body tries to close down between 1.6-2 during the lumpy idle and the STFTs oscillating between low negative and high positive values.

My question to this group is: Has anyone tried with a known BRAND NEW throttle body? I was without my car for 5 months earlier this year trying to get this sorted. The shop is fairly certain that it is a hardware issue and at this point I'm about to just order a brand new 82mm throttle body from an S550 (part number A2731410325) to 100% rule out a bad hardware issue.

SICAMG

Buying a new throttle body will do nothing as many have tried. This is a ECU issue triggering a lean issue.

lost27

Having gone through almost 10 years worth of threads, others have tried different throttle bodies but nobody has ever copped to purchasing a brand new one. Even VRP states that the throttle bodies they sell have a significant failure rate. In my case I had 2 throttle bodies there were not working at all until this 3rd one which was working fine from May until recently.

All of the threads talk in circles about leaks, ECU tunes, different versions of the ME, the supercharger bypass timing, among other things. Not a single tuner has ever chimed in about what could be the issue and folks that "fixed" the issue with the tune have never come back to update the threads on how well those tunes are doing. All of the big name tuners have been mentioned in the threads: Eurocharged, RaceIQ (BIP), OE, and DTK and it seems like for every one of them there are folks that the tune worked for and there are those that the tune didn't work for. The DTK tune is the most recent tune that has been mentioned that "fixed" the issue but that thread hasn't been updated now that we're in cooler weather.

The frustrating thing about all of this is there doesn't seem to be any movement on 100% resolving this issue nor are the folks that were really digging into it around anymore.

It sounds like you aren't experiencing this problem or if you have you've fixed it. Could you post your mods/tune?

SICAMG

I was told in the beginning if I wanted zero issues use a 80mm throttle body ...and that's what I did. A side from the torque management issue that was very slight that was fixed with the TCU.
Did you ever swap back to the 74mm to see what it does ?

GinDistiller

And did you do the idle and in-gear rpm adjustments in STAR? There is a youtube video floating around that details it. Pretty sure it's in these threads but if not it takes 5 minutes to do.

lost27

Yea, that was done. I'm lucky enough to live close enough to Eurocharged ATX so they've been handling all the install and tuning. I figured leave it to the pros.

SICAMG

Don't forget the STAR complete adaptations for the throttle body as well.
I am wondering ....and this really is a long shot, if the new Troy TCU would do anything for this. If you where wanting to buy one I guess now is the time but don't really see it to do anything but who knows.

lost27

This was also done during the install.

VictoryRoadPerformance

Bumping a 2 year old thread intentionally. Here is a compilation of Information Ive gathered overtime from testing and pooling together information from other threads.
This issue has been documented with IQ tunes, Vtech tunes, EC tunes, as well as some private tuners.
The issue is not exclusively related to a vacuum leak
The issue occurs on cars with and without a bypass valves
The issue is more pronounced with larger throttle bodies
The issue has been documented with stock TBs, 80mm, 82mm, 92mm, and 105mm.
Throttle bodies have been swapped which has not eliminated the issue.
The issue is not definitively related to certain throttle positions or Map readings
Map Clamp has not eliminated the issue.
The issue resets with a cycle of the key
A test of the 5v constant at the Map sensor tested out to 5v on a car with the issue meaning another sensor in the circuit is not back feeding and messing up the reference.
Replacing IAT or Map sensor does not resolve the issue.
This issue is not related to TCU tune

The characteristics of the issue are a "Lean condition developed after a period of time driving. The vehicle will stay lean under load and under idle until the key is cycled. The condition will go away temporarily but will re-appear shortly after after put under load.

The issue gets progressively worse over time, going from 20-30 minutes of drive time, to almost instantly under certain conditions, which leans towards a degradation of a component, or a “memory” overload in ECU maybe due to storing error codes over time

There is no confirmation that Varying ME versions effect who does or doesn’t get the error but I believe this could be a determining factor

nemiro

I have a M113K swapped into a Chrysler Crossfire. I had this issue when everything engine wise was stock. It has become more pronounced with the addition of a 77mm pulley and 82mm TB. I have tested many of the items in VRP's list above, and can confirm. I can also add the following:

- I have more than one ECU available, and that the ECU hardware was pretty much ruled out as being the issue
- Wiring has been checked for continuity and resistance
- ECU, throttle body and bypass valve connections cleaned
- Fuel injectors (Bosch 630cc) were blamed and replaced a second set of new
- Checks for vacuum leaks completed
- Cold air intake
- Different (cat-less) exhaust installed
- Crossover plenums
- New plugs/wires
- Different fuel system and rail layout (different feed point for the fuel supply)
- Experimental TCU program to simply test for torque converter lockup issues
- Replaced both upstream O2 sensors

Not all of these were done to track down this problem, but some were, and there were no changes to the hiccup from any of these. Not saying there is not a latent hardware problem still remaining, but it is looking more like a tuning issue.

The hiccup shows up on every drive, but is not 100% reproducible. It does appear to be RPM and load dependent, and when the car gets "into a mode" where this will show up, it can be manipulated to be better or worse by modulating the throttle. It can be made worse by giving slightly more throttle, but not too much. It can be made better by lifting throttle, and re-applying, or by applying more throttle, and pushing through it. More throttle is rarely an option as this seems to show up in traffic situations where more throttle would put you into the trunk of the car in front of you. Lifting or just dealing with it become the only options.

These are the items I can add to the discussion at this point.

VictoryRoadPerformance

I think the theory on Barometric pressure sensor in ECU could be a good lead

One thing in common with all throttle bodies is the change in vacuum. This would make a difference at both idle and under partial throttle.

One thing I noticed on screenshots of live data was "driving distance since fault memory was erased" This could point to an overloaded memory in ECU where it is unable to store more fault codes and automatically kicks it into a limp mode.

And the other theory where the backup map as German tuners have stated is always on the table, but finding a tuner who knows how to access/modify those maps is proving to be difficult.

The next things we are going to try are

Reprogramming and swapping ECU from another car to eliminate hardware altogether or positively identify ECU as problematic
Clamping the Barro sensor in ECU
Manually resetting driving fault memory
Manually overriding backup maps

We are taking screen captures of live data to compare with others Aswell.

VictoryRoadPerformance

Can you clarify that you swapped ECU and problem persisted? was it immediate? or was there a period of driving ok before error came back?

nemiro

Hard to tell on that one, but I would say if it took a while to come in, it wasn't very long. I do believe it to be related to fuel adaptives, but I do not have much to back at up, except for 30 years of tuning experience on other platforms. I have access to WinOLS, but not a "good" definition file for M113K. If I did, I'd start taking a critical look at the underlying problems. I worked out driveability issues in calibrations for many years of my career. These are often difficult to fix, and most tuners are only concerned with what happens at WOT, and less concern for proper calibrations that take top end power and the overall experience into account.