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OK - so this is an attempt at a guide for you M135i & M235i guys. If you feel it is good enough the mods can move it to the 'how to' section.
Preparation
You will need:
- To follow these instructions and learn from my mistakes
- Ideally a 2 or 4 poster, if this is not possible car Ramps or a hydraulic jack with axle stands will do the trick
- Metric socket set
- Metric spanners
- A friend, a second set of hands certainly helps
- Optionally you may want to have external torx bits, i however found my sockets gripped them quite well.
Removal
1) First of all make sure the car is cool... you will be working alongside the exhaust, turbo and gearbox. Burning yourself is never fun!
2) Open the bonnet and remove the engine cover
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3) Pull back the left hand side of the foam cover at the back of the engine bay to reveal the two sensor plugs.
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4) Unplug the connectors and trace the cables back with your hand, you will feel that they are clipped on to the manifold heat shield. Un-clip the cables.
5) Get the car in the air using your chosen method... remember folks safety is key.
6) Remove the under tray from the car. note: there are at least 1000 bolts holding it in place.
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7) Remove the mid pipe exhaust hanger behind the flixi pipe, this will give you plenty of movement in the exhaust. excuse the blurry picture you should get the idea. it literally says exhaust clamp on it.
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8] loosen the torx bolts that hold the downpipe clamp to the gearbox.
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9) loosen the V clamps on the cat. i actually replaced my lower v band due to corrosion. once loose you will be able to move your downpipe around.
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10) Completely remove the torx bolts from clamp and gearbox, the car should pull free. Please keep an eye on the sensor cables.
Install new downpipe
1) Swap the sensors to the new DP, Black wire is UPPER on the DP, and Grey wire is LOWER on the DP.
2) Remove the gearbox clamp from the old downpipe... do not at this stage fit it to your new downpipe. i done this and messed around trying to line up my upper v-clamp for a very long time. So leave it off for now.
3) Almost everything in reverse from here... Place the Downpipe up into position. Hold it in place and try to tighten up the upper V band so the downpipe stays in place. Do not tighten it up at this stage.
4) Line up the lower V-clamp and make it up but do not tighten.
5) Now your sure that both v-clamps are secured and in the correct place you can place the gearbox clamp back on the downpipe and bolt it back to the gearbox.
6) Bolt the mid exhaust clamp back to the car.
7) Now that the mid section is sitting where it should be and the downpipe is in place you can now tighten up the V clamps (Top & Bottom)
8] Rewire your sensors in the engine bay.
9) Start your car and check for leaks.
10) Put the under tray back on and make up all 1000 bolts.
11) Start the car, let it warm up and hoon around like a teenager making big pops and bangs. please note that you will drive like a clown for at least a week.
Hope this helps at least someone
Thanks
Chris
Preparation
You will need:
- To follow these instructions and learn from my mistakes
- Ideally a 2 or 4 poster, if this is not possible car Ramps or a hydraulic jack with axle stands will do the trick
- Metric socket set
- Metric spanners
- A friend, a second set of hands certainly helps
- Optionally you may want to have external torx bits, i however found my sockets gripped them quite well.
Removal
1) First of all make sure the car is cool... you will be working alongside the exhaust, turbo and gearbox. Burning yourself is never fun!
2) Open the bonnet and remove the engine cover
3) Pull back the left hand side of the foam cover at the back of the engine bay to reveal the two sensor plugs.
4) Unplug the connectors and trace the cables back with your hand, you will feel that they are clipped on to the manifold heat shield. Un-clip the cables.
5) Get the car in the air using your chosen method... remember folks safety is key.
6) Remove the under tray from the car. note: there are at least 1000 bolts holding it in place.
7) Remove the mid pipe exhaust hanger behind the flixi pipe, this will give you plenty of movement in the exhaust. excuse the blurry picture you should get the idea. it literally says exhaust clamp on it.
8] loosen the torx bolts that hold the downpipe clamp to the gearbox.
9) loosen the V clamps on the cat. i actually replaced my lower v band due to corrosion. once loose you will be able to move your downpipe around.
10) Completely remove the torx bolts from clamp and gearbox, the car should pull free. Please keep an eye on the sensor cables.
Install new downpipe
1) Swap the sensors to the new DP, Black wire is UPPER on the DP, and Grey wire is LOWER on the DP.
2) Remove the gearbox clamp from the old downpipe... do not at this stage fit it to your new downpipe. i done this and messed around trying to line up my upper v-clamp for a very long time. So leave it off for now.
3) Almost everything in reverse from here... Place the Downpipe up into position. Hold it in place and try to tighten up the upper V band so the downpipe stays in place. Do not tighten it up at this stage.
4) Line up the lower V-clamp and make it up but do not tighten.
5) Now your sure that both v-clamps are secured and in the correct place you can place the gearbox clamp back on the downpipe and bolt it back to the gearbox.
6) Bolt the mid exhaust clamp back to the car.
7) Now that the mid section is sitting where it should be and the downpipe is in place you can now tighten up the V clamps (Top & Bottom)
8] Rewire your sensors in the engine bay.
9) Start your car and check for leaks.
10) Put the under tray back on and make up all 1000 bolts.
11) Start the car, let it warm up and hoon around like a teenager making big pops and bangs. please note that you will drive like a clown for at least a week.
Hope this helps at least someone
Thanks
Chris
