[rsmallwo]

Hi All,

I've had a look round the search function and not seen much concerning my issues.

For the past several months I've noticed the DCT hesitates when selecting 1st or 2nd gear when it's rolling to a stop (under slight braking) when you go to accelerate you notice a long lag before the clutch even attempts to engage. It doesn't seem like clutch slip as it handles hill situations quite well and it doesn't feel like it's even attempting to slip the clutch abit. This issue can result in unpleasant driving characteristics, even my girlfriend comments the car feels heavy from standstill and then jerky when it engages the clutch.

I have looked for this issue across google and there are alot of complaints about the DCT in general being hesitant. But I've had the car 3 years and it didn't do this back then, it just had that "normal" auto tranny uncertainty in these typical scenarios.

My other issue which might be connected is that in the past few months when oil temp is all warmed up when conducting kickdown overtake's the amber DCT overheat warning light has come on and cut power. I wasn't driving the car particular hard. Leaving the car a few hours and all was fine again. This only occurred the once.
On a track day last week the DCT overheat warning essentially came on after several laps and then refused to go despite letting the car completely cool down to cold, it cut the power by 20/30% and kind of ruined the track day for me.

What are people thoughts and questions? The car is a 35i, 2009 build with 90k miles

Thanks,

[Smokey33]

Is the car modified? and what mode were you in when the errors came on?

I had a DCT overheat warning once. The car went into limp mode and said DCT overheated. Im pretty sure it was because I wasn't treating it correctly, I was driving in D. Back then I was running just a MHD stage 2 generic map

I had the gearbox oil topped up, and the pan/screws and that replaced, ive no idea whats involved AP auto in Telford did the work.

Since then not a single issue. Ive got auto kickdown disabled in MHD and I treat the box like a manual. Also the car had a proper custom remap from BQ tuning who is regarded as one of the best with the N54 and DCT. Mines running 385BHP at the wheels and 420lbs/ft.

I have heard these aren't great on trackdays with continuous abuse.

[jazz5000]

Also had the same issue once, Was when the dct box was in D and using kickdown,

Have never had this issue in "sport" and DS/M

Smokey33 how many revisions are you on? Still need to dial mine in on the 1st revision of BQ's custom map

[Smokey33]

Originally Posted by jazz5000

Also had the same issue once, Was when the dct box was in D and using kickdown,

Have never had this issue in "sport" and DS/M

Smokey33 how many revisions are you on? Still need to dial mine in on the 1st revision of BQ's custom map

Exactly the same as me. Are you using MHD? Id turn the kickdown off if you can.

A lot of the problems seem to be when its in auto and booting it. I let the car warm up in D driving like miss Daisy, but id always recommend using M and the paddles any other time.

I had about 7 or 8 maps before we were all finished. Are you a N55 with it being a 2010?

[jazz5000]

No mines also 2009 N54

[Mayorie]

Originally Posted by jazz5000

Also had the same issue once, Was when the dct box was in D and using kickdown,

Have never had this issue in "sport" and DS/M

Smokey33 how many revisions are you on? Still need to dial mine in on the 1st revision of BQ's custom map

+1

[rsmallwo]

The car is running a remap and since the remap It's not had a gearbox overheat issue or the hesitation issue until the past several months.

Before these issues started I have has the oil sump pan replaced twice on the DCT, first time was to maintain it and the 2nd time was because it was leaking. The gearbox has been completely out the car and the megatronics seal, shaft seal and electronics connector seal have all been done. They all got done after i start noticing the hesitation issue (thought doing this might help in some way) However, I only got over temp issues after this work had been carried out

I've tried to research if the e92 m3 dct would fit in my car as they have the same generic code for the box of GS7D36SG. But It seems the M car box is not quite the same size overall. They have different official BMW part codes aswell. Shame really as i can't seem to find a donor box for my car but there are quite alot of M car boxes knocking about.

It's been looked at by my independent bmw garage on 27th but they've already applied a software update to the car and said "don't think the hesitation issue is fixable" hence me looking at replacing the box

Thanks,

Originally Posted by Smokey33

Is the car modified? and what mode were you in when the errors came on?

I had a DCT overheat warning once. The car went into limp mode and said DCT overheated. Im pretty sure it was because I wasn't treating it correctly, I was driving in D. Back then I was running just a MHD stage 2 generic map

I had the gearbox oil topped up, and the pan/screws and that replaced, ive no idea whats involved AP auto in Telford did the work.

Since then not a single issue. Ive got auto kickdown disabled in MHD and I treat the box like a manual. Also the car had a proper custom remap from BQ tuning who is regarded as one of the best with the N54 and DCT. Mines running 385BHP at the wheels and 420lbs/ft.

I have heard these aren't great on trackdays with continuous abuse.

[jazz5000]

When i was running a JB4 on mine i used to get abit of hesitation when pulling out at junctions,

Since switching to MHD stage 2+ map and then over to a custom map havent had that hesisation since,

Could possibly be the map?

[AD18]

I've mostly had positive success with the car on track, the let down for me has mainly been the brakes even when I have upgraded the pads.
The one occasion the car went into limp home mode was when I was on track in the summer when it was pretty hot, 25C+. I think the car didn't last more than 3 laps but I let it cool down and all cleared however i didn't go back on track so I certainly can relate when you say it ruins the day.
I wasn't aware the E92 M3 had different DCT hardware, I thought it was actually the same unit but just the software was different, could be wrong though.

[Smokey33]

The m3 has a extra cooler on the DCT.

Hmmm strange. Try joining the BMW DCT group on facebook, there very good on there.

Who did the map?

[rsmallwo]

The remap was done by a place in sheffield of which the name escapes me now......

The gearbox has been fine with the remap for several months/years. I don't think it's values would change over time. Suppose one option would be to remove the remap as a test.

Originally Posted by Smokey33

The m3 has a extra cooler on the DCT.

Hmmm strange. Try joining the BMW DCT group on facebook, there very good on there.

Who did the map?

[rsmallwo]

My garage don't think I have a gearbox issue, there are no error codes for it.......there are error codes for 30FF though. After replacing actuator pipes and checking solenoids he thinks it's my turbos (though I don't have any chattering, exhaust smoke or whine/noise)

I also have a cracked rocker cover which he thinks could cause some of the hesitation when decelerating.

Busy looking for decent prices on reconditioning my turbo's or even an upgrade......I'm still not entirely convinced it's just a boost issue, but it is weak at low end and better abit at top end, so that would miff the clutch off when engaging I guess

Any recommendations for Turbo work in the Yorkshire/midlands region?

[Smokey33]

Check out PMP cars in Nuneaton. Bit of a drive for you, but there excellent. N54 specialists.

Id try a different map first, and only drive in spirited fashion in M and sport mode.

[rsmallwo]

Originally Posted by Smokey33

Check out PMP cars in Nuneaton. Bit of a drive for you, but there excellent. N54 specialists.

Id try a different map first, and only drive in spirited fashion in M and sport mode.

Haha!! Car's booked in with them for mid May. They seem to get good reviews and are price competitive despite the distance I'll need to travel.

[Smokey33]

Originally Posted by rsmallwo

Haha!! Car's booked in with them for mid May. They seem to get good reviews and are price competitive despite the distance I'll need to travel.

So what have you actually booked?

I would send Dimitri carty a message on facebook or email him google BQ tuning.

[rsmallwo]

Originally Posted by Smokey33

So what have you actually booked?

I would send Dimitri carty a message on facebook or email him google BQ tuning.

Rocker cover replacement and fix the 30ff underboost issue (which may or may not rebuilding the turbo's). Will also get the oil changed.

I wouldn't expect my existing remap to have changed in someway, ECU software is pretty static by nature.

If the car still hesitates after this work then I'll have them look at the DCT or other potential causes. The car did have it's inlet manifold walnut blasted at 67k, its at 91k now so i don't think it particularly needs doing again but I'll let them advise/show me pictures. I did have my PCV replaced with the RB unit when it was done originally.

[rsmallwo]

So, car has had the following work completed:

Rocker cover replacement
Walnut blasting of manifold
Turbo Wastegate replacement

This had fixed the 30ff underboost issue.

I did think it fixed the "hesitation issue" as per:

"For the past several months I've noticed the DCT hesitates when selecting 1st or 2nd gear when it's rolling to a stop (under slight braking) when you go to accelerate you notice a long lag before the clutch even attempts to engage"

I've also thought that maybe it could be a throttle issue rather than gearbox one as throttle inputs can feel oversensitive in sport mode and in normal mode from cold the car feels like it wants to kangaroo abit in first but it shifts up before doing so. This doesn't persist for long but in some low throttle positions it feels over sensitive I guess.

Simple answer would be to floor it everywhere, but my commute doesn't allow this.....nor does social convention!!

I really wish the issue wasn't so intermittent, makes driving it a chore rather than a joy.

[rsmallwo]

Should I try to remove the remap to see if there is an issue when stock or concentrate on the hardware?

[Smokey33]

Have a word with ********

[rsmallwo]

I've removed the remap and gone back to stock. Still get the issue though it's a touch less noticeable. Sounds like a hardware issue to me..

I'm thinking either DCT or throttle related. I mentioned before that even when 1st gear has been engaged the throttle feels quite jerky to relatively smooth inputs. More so first thing from cold. Though the Hesitation issue persists at all temp's.

I've read other posts about throttle issues, but these seems more related to manual cars and not DCT. The Throttle Body has been out the car when the walnut blasting was done. Nothing untoward was reported, though I didn't specifically say check the throttle body.

[rsmallwo]

Took the car to a gearbox specialist and they thought the issue was engine side as it wasn't clunking/slamming gears in like he would expect for a gearbox fault. However his level of explanation and expertise I am still in some doubt.

Took the car to look at the engine and they tested the vac solenoids and turbo actuators and they test as brand new tolerances. Also had them swap the vanos solenoids over with each other to see if the issue moves around due to vanos timing but not difference or fault codes.

Feeling pretty miserable about my lack of progress. My experience of this car is nothing but difficulty after difficulty, would instruct people to stay away from this car if I was asked and I'm pretty patient with this kind of stuff.

[Smokey33]

You are spending a lot of money chasing problems that might not even be there.

A remap from the best DCT N54 guy in the business will be a lot more cost effective and could cure all your issues.