Someone Else's Problem: One for the other foot? A French Impostor? - 2005 Smart Roadster Coupé

It’s just the stalk? That’s really nice.
It’s just the stalk? That’s really nice.

Yup. Well, the stalk and the switchgear behind it.


Image pinched from eBay, they're all using the same image anyway so I have no shame.

This is a straight swap for the wiper stalk that is already there and just needs the extra plug, I now know it has, connecting up. The SAM unit was listed as having CC enabled when I bought it and with the paddles working I have no reason to doubt that claim.
Well tickle my privates, it's nearly two weeks since I posted that last update. Since then, some events have occurred.

Firstly, the stalk arrived and was fitted. Unfortunately, despite my clear recollection (or not) of the eBay listing when I bought the replacement SAM and its mention of cruise control being enabled, it didn't work. Well, shit. Fine, I'll arrange with S2 Smarts to have it coded as I pass by.

You see, last weekend I made a little trip down the south coast to visit MWF, HWF 3.0, SonWF, CatWF, DogWF and some bloke from Slovenistan. I was using the M25, so a trip in to Watford is only a little detour and wouldn't add much to the journey. As it turned out, something else I could've never foreseen would add more time to the journey.


All seemed fine when I started the journey and it wasn't until I looked in the right door mirror and saw steam pouring out from the back of the car that I realised something was wrong. I should've noticed the temp gauge climbing before it got to this point but it's not in a natural position to glance at while driving normally. I crawled off the motorway at the next exit (fortunately I was already pretty much on top if it) and stopped at the first lay-by I found and opened everything up. It quickly became apparent that I had lost a load of coolant and that the radiator was cold.

The AA was called out and long story short, there was an airlock in the system that prevented the thermostat from opening and saved the honey bee that was sitting on it from being cooked. Some fresh AA water later and after a check over and a quick drive through the back roads to the next motorway services, everything was fine. Never had an issue after that and no damage was done, apparently it's common with Roadsters as the header tank is barely higher than the thermostat housing. I got to S2 Smarts just in time to get the CC done and it works beautifully, a great addition on a long drive. The rest of the drive to MWF HQ was great, there are some very nice roads down there.

On Saturday we went out for a scenic drive and did a car swap, me and Ice went in Maisie the MX-5 and I reminded myself how a clutch pedal works (only the bobtail is a manual and I haven't driven that for at least a month), while MWF and SonWF went in the Smart. We stuck the GoPro on the MX-5 and this was the result (apologies for the wind noise, nowhere to mount the mic).

Then we swapped back and headed for a taster at a fantastic local pub. Note my massive fuck-up at the end where the GoPro mic adapter bites the dust.

The drive back was also fantastic as I could have the roof down the whole way, being stuck in a queue on the M25 and watching planes pass over through the open roof as they approach Heathrow is really something. I have some other bits from the weekend but will post them in the meet thread.
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I wouldn't expect less from you. - Back in form. That's the spirit. Good show. LOL

I'm really thinking now that I should only buy air cooled cars from now on. :LOL:
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You should buy a tiny trailer to pull tiny car with large car. I have sat behind larger pickups in the fiat and been like "hmm.... ALMOST bug enough" looking at the truck bed. And this is even SMALLER so.
You should buy a tiny trailer to pull tiny car with large car. I have sat behind larger pickups in the fiat and been like "hmm.... ALMOST bug enough" looking at the truck bed. And this is even SMALLER so.

How about an even tinier trailer pulled with a tiny car? :D


Borrowed from this Imgur album from the Roadster Times 2019 show.

Even with a car this tiny I would have to pass another driving test in this country to tow it on a trailer, something I've actually wanted to do for a long time but it's a low priority, learning to weld would be a higher priority. I could tow the roaster with a tow dolly if I wanted to as it's a robotic manual instead of a proper automatic although I dread to think what Bugsy's fuel economy would be like with an extra 790kg behind it. :LOL:

It looked lost on the little van-based tow truck I used to take it down to Watford a month or so ago after the coolant pipe failed and those things aren't big at all.

I would love to have something like Mr. Aging Wheels is building or like The Escargot that the guys from Bad Obsession Motorsport are working on.
I see you're missing the Beetle. :p:D
More like I suck at phone typing :p
I don't miss the beetle it is in the driveway i just updated the thread for it.

Also a scorpion is still a bug so technically you could say both my cars are bugs :LOL:

And yeah it probably wouldn't be worth it most of the time but it would be a fun option for a trip. I always wanted something on the lines of a vw bus but that would be A Lot of car for me most of the time on these europe like narrow cow path roads.
To help prevent cooling issues in the future I bought an Autool X60, a £31 bit of kit that reads from the OBDII port and offers a coolant temp alarm among many other things.


My original plan was to replace the existing coolant temp gauge with this little thing, however after taking everything apart...


...I found that it wasn't going to fit properly and would frankly be too far away to see properly. So I tried a bunch of positions:


I went for #5 as it was right in front of me and doesn't obstruct anything. Just for clarity as it was hard to get them in the right position, #4 was supposed to be in front of the rev counter in a way that didn't obstruct it or the lights hidden inside the black area.

So I made a bracket from an old HDD cover. It follows the shape of the clocks as best it can and from the front the new gauge doesn't cover anything, I also went for this idea as I have two of these plastic trim parts (along with a spare white set of clocks) so don't feel bad drilling holes.




The USB-OBDII cable fits snugly in the back and should be as good as invisible when it's fully installed.
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Oh, snap! Screen is fitted. Tricky to see here as it's rather reflective and this was before I moved the light sensor that they stupidly fitted in a place where it will always be covered by the USB cable, causing it to think it's night time and dim the brightness of the screen.


The data is there though, the all important temperature next to voltage, a pointless shift light at the top and I forget what the bottom bar is set to. Currently the main display is set to speed but it can be many different things such as live MPG or average MPG (that seems to reset when you stop for some reason). All wires are tucked inside the dash.

The temp warning also works and is set to 95 degrees science, it beeps and flashes in a way that even I can't miss. The fan kicks in at 100 degrees, I may bump the warning up to 105 as it's only when it gets above this, indicating an airlock or other fault, that I'm concerned.

Tempted to paint it to match, lots of scope to fuck it up though...
Much easier to see at night and with the brightness cranked up. Unfortunately I found out that the MPG figure is a live counter only and doesn't do average. Meh.

Got myself a new Quechua tent for the roadtrip and Ringmeet, specifically so that it fits in the back of the Roadie. This is the two man tent so is only 66cm in diameter when packed instead of the 77cm of the previous one and it makes all the difference!

You may remember, the old tent hangs over into the path of the roof so no opening or closing on the move.

New one clears nicely with the same suitcase beneath it. The bars should stop it moving but I have other ideas if that seems to be a problem. Photography skills have improved massively, no finger in the shot.

It can be wedged behind the front seat but I imagine this would be rather uncomfortable for any passengers. It can even be wedged in the frunk if the roof bars are still on the car

The tent is the Fresh & Black, aside from fixing the size issue it should also be nicer in the mornings where it sometimes became too warm and bright inside my old tent. Doesn't have the built-in lights though, boo.
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Time for a long overdue, post-roadtrip update to this thread. I've been putting this off until the work was complete and, frankly, because I'm lazy.

Back story:

In relative terms compared to the problems I had on the trip the Ringmeet and back last year, the Smart performed very well during the roadtrip. The lack of power became very apparent on the high-altitude mountain passes, where the air was too thin to allow the boost provide sufficient boost and the robotic clutch hated the steep hills we occasionally encountered, however these were minor issues and the car was great fun on the trip.


The major issue that only cropped up once during the main part of the roadtrip was good old limp mode.

Two days before I was due to leave for the roadtrip I needed to drive the Roadster to work, around 17 miles each way. I wouldn't expect this to be a problem but around 12 miles into the morning journey the thing dropped into limp mode for no apparent reason. The rest of the drive was on slow roads and in traffic so I didn't do anything, just parked up and left it for the day. On the way home I stopped and reset it before I got to open roads where I would need more power, I also checked over what I could and found no problems.

That Sunday was S2Smarts' open day and the first day of my roadtrip. I had no issues with the car getting down to Watford but got them to run a diagnostics check, the only thing that showed up was the MAP sensor. I would've replaced it there and then but they didn't have one in stock. I got my spacers fitted and enjoyed the BBQ, at the end of the day I set off on my merry way to Kent.



Fast forward through the roadtrip, limp mode happened once on a day that I can't remember and I began disconnecting the battery every night to reset the computer. This worked fine until day 7, when the thing just kept going limp on me. The next morning @D-Fence spoke to Mercedes and we got a new sensor from the stealership in Freiburg, however this didn't fix the problem and it went into limp mode several times on the way up to the 'Ring.


At Ringmeet I tried to investigate the issue by removing the rear end, however I didn't find anything. It turns out that there was a problem to find but I wasn't digging deep enough. I attempted a lap of the 'Ring and it went limp on me again, meaning the lap was slower than my Discovery but still faster than Dave's Kangoo at .

At some point, I don't really remember when, I noticed that the hose from the intercooler to the intake manifold wasn't seated correctly and the hose was in very bad shape. Some previous owner or mechanic had replaced the hose at some point and it wasn't the right size, added to that it looked like that had cut the hose by biting through it with their teeth. Ultimately, I think this was a red herring and I actually caused the problem rather than resolving it when I tried to tighten the hose clamps, I then had more problems with the hose coming off and leaking boost. Even with assistance from @nicjasno, the hose wouldn't stay put.


I managed to get home with the hose in this state, slightly lacking power due to it's sorry state but without limp mode. It made some really funny squeaking noises at times, I tried to record them with my phone but forgot that it was paired to the bluetooth module in the dash that has no microphone...

Fixing it:

Anyway, when I got home I ordered the parts to sort the issues. Two silicone intercooler hoses, I only needed the one that replaced the plastic hose and rubber coupler going from the intercooler to the manifold but they came as a pair, a silicone TIK intake pipe and associated fixings. I also had a replacement boost control (cycle) valve as it's cheap and it's buried deep in the engine so I may as well replace it while I'm in there.


Note the length of the little dingus end pipes coming from the long intake hose, they will become relevant.

The back end of the Smart was removed again, along with the crash support this time so I could dig a little deeper. I disconnected the old cycle valve and found that one of the small rubber pipes was split, the same one that had caused me problems last year!


When this pipe was leaking last year it was obvious that something was wrong due to overboosting, however there was no telltale at all this time around, other than limp mode. I considered the option of buying the genuine parts from Smart but it was suggested on a Smart forum that I would benefit from moving the cycle valve to a more accessible place so I could replace it should it ever go wrong again. I ordered some high-temp silicone pipe from an eBay seller.

The next weekend rolls around and the new pipe is here, so I get stuck in with removing the old cycle valve and pipes, making these highly detailed images to remind me which pipe goes to which side of the valve.



The two intercooler hoses were then fitted, a bit of a struggle due to how tight they are and a lack of space in the engine bay, but at least they won't be popping off any time soon.



The cycle valve can just be seen at the top in the second photo, it was recommended that I zip-tie it to the intake hose. New lengths of vacuum pipe were then threaded down and connected up.


I attempted to fit the intake hose, but found that the dingus end pipes were too long and the breather pipes from the engine wouldn't fit properly. I considered complaining about this and sending the hose back, but after digging through old Smart forum posts I found someone who had this issue back in 2011 and found that these dingus ends sometimes need to be cut down. So that's exactly what I did. I had to cut off the original crimp clamps so got some genuine Jubilee clamps to replace them.


The engine breather pipes fitted much better and I could finally reassemble the whole thing, about three weeks after I started. This is now the view of the engine bay:


I actually didn't want blue hoses at first but it's all the seller I used had in stock, if I wanted black I would need to buy them elsewhere at a considerably higher price. The smaller pipe was available in black but I felt that blue is easier to see in the dark engine bay and matches the bigger hoses.

I went for a test drive today, listen to how it sounds now.

I also have a new sticker on the Smart!

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Apologies for another long post, it's worth reading to the end though!

It's been a week since I posted last and frankly I'm disappointed in all of you. ?

The video I posted as a test of the car actually has it going into limp mode at 2:20 and surprising me. Unfortunately all of this work didn't cure the fault and I was back to the drawing board. I've pretty much ruled out everything on the boost control side of things, short of a major turbo or manifold issue that I can't really diagnose or fix.

Last week I was reading up on other causes of limp mode and one of the reasons listed was power brown-outs. I've had issues with slow cranking and this battery going flat before so it's possible that under full acceleration the thing couldn't provide enough juice. I got the battery tested by a local company and it was showing as 38% health with an internal resistance five times that of a new battery, so I bit the bullet and bought a new one for just under £80. This one far exceeds the capacity of the old one so should give better performance in the long run.

Anyway, it didn't fix it. The first time I drove the car again I accelerated and it went limp on me once again. However, this time I was watching the boost gauge go all the way up to the 1.5 bar mark and past it. At that point I had an inkling of what was really going on.

Remember last year when I posted this picture of the wastegate actuator connection to the turbo wastegate?


I had no measurement to go on when reconnecting the actuator so I just guessed without really thinking and enjoyed the extra power gained from not having the wastegate flapping around. It seems that I guessed wrong and this may have been the cause of every limp mode trip since.

This morning I decided to have a look and marked the original location with yellow paint.


To open the wastegate more, I needed to loosen off the adjuster and lengthen the rod. I backed it off a bit and added more yellow paint, I could've just left it at this but noticed on online pictures that there should be a locknut on this rod. Fine, I'll remove the whole thing again and add the M6 nut I got from my supplies.

Loosening the adjuster was difficult due to its location and knurled-knob nature, there are very few ways to attack it and I'm now missing a few layers of skin on the edges of a few of my fingers. A squirt of penetrating fluid helped it and it gets much easier towards the end. Clue

While it was off I checked that the wastegate was free. No problem, nice and free. The nut went on the actuator rod and then the adjuster. When winding the adjuster back on, it was easier at the beginning as before and became more difficult, with the fluid lube helping but it was still fiddly and annoying. I started to wish that I had never removed the whole thing to add the locknut as it didn't seem to need it, it hadn't moved before. Clue

I got it back to the position I was happy with.


Then tightened the locknut. Checked that it still moved and it did, job done. Or is it? When I had extracted my head from under the car I thought about it, the arm moved but not much. Then it hit me like a slippery fish - I was fighting the spring in the actuator the whole time so there was only a tiny bit of travel left and the wastegate was only opening a fraction. No wonder it was overboosting!

Frankly it's a miracle that no damage was done in a year and a half but odd that the specialists didn't notice it, I would've thought that checking the wastegate would be part of the 'C' service but meh. I went back under and backed it right off until the actuator stopped retracting under spring pressure, put a single turn on and locked it off. you can see how much longer the rod is now.


Funnily enough, the power delivery is now much smoother and it doesn't go into limp mode. It's a little stunted at the moment, stopping at around 1.2 bar, so I can dial in another turn. Maybe it will actually be fixed this time!
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Put a couple more turns in the wastegate adjustment today, now it's perfect. With my foot flat to the floor in fourth it will go smoothly from 30mph to the, er, redline speed while sitting at 1.5 bar and with no limp mode.

It's smooth enough that going from a standing start to the speed limit with my foot flat down and letting the car change itself at said redline is actually nice.
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Hi Matt

I must know, how did you get your Autool X60 working in the Roadster? I’ve just bought one for mine and it fails to connect!

I’d really appreciate if you have any insight at all!
Hi Matt

I must know, how did you get your Autool X60 working in the Roadster? I’ve just bought one for mine and it fails to connect!

I’d really appreciate if you have any insight at all!


Unfortunately I didn't have to do anything with mine, it just worked out of the box. The mini-USB connection on mine is quite flaky now so maybe something isn't quite right with the one on yours, I've had trouble with this type of connection many times in the past. My car was re-mapped before getting the X60 too, maybe that unlocked something in the ECU.

I would suggest trying it in as many other cars as you can to see if it ever connects, maybe it's just faulty. I'll check the firmware version on mine when I get a chance.