Draining Unless you like to be scalded, wait until the car is cold. Remove the front service panel and undo the cap to the coolant header tank. Look under the car at the engine over to the right. Just behind the long drive shaft, partially hidden by some...
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Engine
451 Coolant Radiator Removal
If you have a leak in your radiator, fit a new one, don't rely on fluids like RadWeld. Changing the front coolant radiator is easy but actually getting to it is a long task. If you don't have air conditioning, it'll be the only time that you are glad that you don't....
451 Diesel 54bhp Safe Mode
When they changed the 45bhp diesel 451 to a 54bhp diesel 451, they added emission reducing systems that caused a shit load of trouble.
451 DPF Regeneration
What Is A DPF? It's a diesel particulate filter, it's inside the exhaust. It catches all of the particles of soot from the engine. This improves the quality of the emissions from the exhaust. Do I Have A DPF The smart fortwo 451 diesel manufactured after October 2009...
451 Driveshaft Seals
If you look at the driveshafts where they exit the gearbox and notice oil everywhere, your driveshaft seals are crap. These seals are a lot more important on the 451. I'll explain the reason this later. Firstly you'll have to remove the driveshafts. Use a pry bar or...
451 Dump Valve
Because I wanted a dump valve on my 451 turbo, we spent thousands having having custom silicone pipes made by Forge Motorsport. They cost us an absolute shitload each so we stuck the rest on SmartMods just in case anyone else wants to do the same. This is the T piece....
451 ED Inverter Removal
Every 10 months or so, my 451 ED would suddenly lose power and show "Drive Sys Eng Off". Even though it would restart immediately after turning the ignition off and on again, you had to come to a complete stop in order to restart the car. Somewhat scary if you were...
451 ED Onboard Charger
I'd been driving my 2013 451 ED for over 4 years with very few issues. Once a year it would cut out but restart with no issues immediately. The error code was about the contractors and they were quite loud when they closed. Then in Q3 2022 I started getting a warning...
451 Engine Mount Change
The 451 engine mount suffers badly from wear which allows too much engine movement, swapping it is very easy.
451 Engine Mount Repair
The engine mount for the 451 is quite poorly designed and splits causing the engine to move a lot.
Considering the cost of a new front engine mount you may as well just repair the original one.
451 Euro4 Exhaust Retrofit
The Euro4 and Euro5 exhausts are very different but it's easy to retrofit.
451 Exhaust Removal
Fitting an exhaust to a non turbo smart fortwo 451.
451 Exhaust Types
The smart fortwo 451 ran from 2007 to 2014 and in those 7 years we saw a tightening of the emissions laws in Europe which meant that 451 exhausts changed. Due to the confusion, it seems necessary to create a visual list so people know what they need should they need...
451 Failed Clutch Actuator
Car Starts & Revs But Doesn't Move Yep, very common now on the 451. Snapped Clutch Actuator Spiral Gear The 451 and Forfour have very similar clutch actuators, both of which suffer from this same fault. Bigger motors and stronger compensation springs for quicker...
451 Fortwo Coolant Leak
If your car suddenly overheated and you seem to have a waterfall somewhere behind the engine, there's a good chance you have a split coolant pipe.
451 Fortwo Earth Upgrade
Upgrade the 451 Fortwo earth leads
451 Gear Change Motor Clean
Gear change motor failures are becoming a lot more common now. There are 2 motors. The 1st motor controls gear 1, gear 3 and gear 5. The 2nd motor controls gear 2, gear 4 and reverse. One will generally fail so you'll normally have issues with alternate gears. It's...
451 Gearbox Fluid Change
Fortwo 451 Petrol Non Turbo (Including MHD) The transmission fluid change is similar to that of the older smart fortwo and Roadster. The main difference is the position of the draining hole. It is now on the right bottom side of the transmission housing. The upper...
451 Gearbox Motor Removal
If you have a non turbo model, great, you just need to remove the air inlet pipe to access the gear change motors. If you have the turbo petrol or diesel model, things are a bit more convoluted. Remove the fan, intercooler and scoop. As there are 2 motors, there are 2...
451 Gearbox Removal
Chances are, if you are removing the gearbox for some reason, your engine is still in the car. There are pros and cons. The pros is that the engine is easier to steady because at one stage, the engine will be held up by 1 engine mount. The cons is that you have less...