Smart Fortwo DCT Mechanical Problem

nlel1975 · 18 Dec 2022 at 06:28

Six weeks ago I accidently went through a big puddle. I didn't see it until too late. Ever since then my car makes a rough sound when I put it into neutral and let it roll back.

Its fine in Drive and Reverse. I usually park on a slight slope in the residents carpark where I live and I put it into neutral and let it roll back before putting it into Drive and setting off.

Any ideas what might be the cause?

Thanks.

godinman · 18 Dec 2022 at 07:34

Could be something as simple as some plastic trim under the car dislodged and rubbing when you go backwards?

nlel1975 · 18 Dec 2022 at 09:58

godinman said:
Could be something as simple as some plastic trim under the car dislodged and rubbing when you go backwards?

I’ll have to book it in with the dealer, I’m expecting a £600 bill.

Semple · 18 Dec 2022 at 10:00

I'll sort your trim out, but I'll do it for the bargain of £599!

nlel1975 · 18 Dec 2022 at 10:09

Semple said:
I'll sort your trim out, but I'll do it for the bargain of £599!

Main dealer prices mate, they’re supposed to be well trained. Might not be that much anyway.

nlel1975 · 19 Dec 2022 at 13:00

Well my cars booked in, it will be £86 to inspect it and they will advise me from there. Glad the wheels are in motion.

nlel1975 · 21 Dec 2022 at 16:06

I've been searching google seems like a common problem...

https://www.google.com/search

"The grinding sound could be coming from multiple sources, ranging from the serpentine belt drive system, to cooling fan motor, wheel bearings or even driveshaft or transaxle."

Goes on to say...

"The best way to determine the source of the noise is to have a professional mechanic complete a car is making a noise inspection."

Which is what I am doing, no way I could figure this out on my own.

tom_e · 21 Dec 2022 at 16:12

Unless it's something very obvious these sort of issues get very expensive very quickly if you're paying dealer rates for them to look for it.

nlel1975 · 21 Dec 2022 at 16:19

tom_e said:
Unless it's something very obvious these sort of issues get very expensive very quickly if you're paying dealer rates for them to look for it.

I’ve got no choice I have no mechanical knowledge or know of anyone who does and I need it fixed. How much are we talking, I only have £2900 in my bank account, if its more than that they'll have to keep the car as collateral. Maybe I could claim on insurance?

jpaul · 21 Dec 2022 at 17:35

sounds like dct/clutch(transaxle) related ... not wheel bearings/belt/cooling fan which would make more noise at speed

eg. below the thing about resetting the mercedes originated smart dct sounds interesting to try.

Clutch Actuator Story

www.smartcarofamerica.com

nlel1975 · 21 Dec 2022 at 17:38

Well at the end of the day they’re inspecting it for £86 and if I can’t afford to repair it I’m not obligated to go ahead with the repairs. If it is more than I can afford I can always look at making an insurance claim maybe?

jpaul · 21 Dec 2022 at 18:16

...if it was new in 2019 will it squeeze in under warranty ?

nlel1975 · 21 Dec 2022 at 18:24

jpaul said:
...if it was new in 2019 will it squeeze in under warranty ?

No three year warranty ran out February this year.

nlel1975 · 22 Dec 2022 at 12:15

I just hope they are professionals and can diagnose the fault easily the first time round, I would hate to have work done and still have the problem requiring further visits to the dealership.

That is one of the reasons I’ve booked it in to the main dealer, hopefully they are the best trained and not cowboys. Couldn’t risk going to a smaller garage on a job like this in case they’re mechanics are monkeys.

Kenai · 22 Dec 2022 at 12:26

Don't get your hopes up, you'll probably get a report saying "No noise observed" for your £86

Armageus · 22 Dec 2022 at 12:27

nlel1975 said:
That is one of the reasons I’ve booked it in to the main dealer, hopefully they are the best trained and not cowboys. Couldn’t risk going to a smaller garage on a job like this in case they’re mechanics are monkeys.

Unfortunately you mind find it's the exact opposite of what you expect. Main Dealers often follow what their computer says in terms of fault diagnosis rather than employing any degree of common sense.
If their "flow chart" doesn't deal with a situation, you may find that they don't have any more of a clue than you.

nlel1975 said:
If it is more than I can afford I can always look at making an insurance claim maybe?

Normal car insurance will not cover this

nlel1975 · 22 Dec 2022 at 12:32

Armageus said:
Unfortunately you mind find it's the exact opposite of what you expect. Main Dealers often follow what their computer says in terms of fault diagnosis rather than employing any degree of common sense.

Would any other garage be more clued up? I do not know who to trust.

nlel1975 · 22 Dec 2022 at 12:36

Kenai said:
Don't get your hopes up, you'll probably get a report saying "No noise observed" for your £86

I’m going to get the delivery driver to put it in neutral and let it roll back so he can hear it.

Armageus · 22 Dec 2022 at 12:45

nlel1975 said:
I’m going to get the delivery driver to put it in neutral and let it roll back so he can hear it.

Just an odd thought, but it may be rolling in Neutral isn't something that you should be doing with a DCT.

Why not just put it in Reverse? (you aren't saving any fuel)

Even a quick glance at a smart owners manual says:

Neutral
No power is transmitted from the engine to
the drive wheels.
Only shift to position N when the vehicle is
stationary.

nlel1975 · 22 Dec 2022 at 12:47

Armageus said:
Just an odd thought, but it may be rolling in Neutral isn't something that you should be doing with a DCT.

Why not just put it in Reverse? (you aren't saving any fuel)

I’ve always done it that way it hasn’t caused a problem, no need to put it into reverse it will roll back a few meters just fine then into drive.