Manifold removal question

Would it be okay to remove bolts from the manifold with an impact wrench
I'm not sure if this would be a good idea or not but if you have remove one before in this way and think its okay please let me know.
Just checking because i think i heard someplace that it was not a good idea to use in this area and i want to make sure im doing things right so i dont break or damage the the studs etc.
Thank you

Edit :- A Google search returned the answer that it is okay to do this.
But its also wise using. A breaker bar.
Its always best to check first.
 
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My next problem in Haynes manual it says to disconnect a/c pipe.
At a glance I was confused how does one go about disconnecting this.
After a Google search I got the answer that it is spring loaded and you have to press this spring back so the pipe can disconnect.
Not sure this will be exact same for the k12 series.
A question tho. Would this pipe let the gas escape when disconnect or is the pipe just to send the gas into the cabin a.c.cooler system?

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So now I have tried a few things to remove I'm going to get a nut splitter tool as a back up.
Was looking at them along while back but they don't work on bolts.
Not really sure if it will fit or if I can get a turn on it that way but decided I might as well grab one and see if its any good.
At this point I'm really annoyed at having to purchase so much tools.
Because I'm finding it hard to fund my parts list already and that has halted until I'm able to complete the next three tasks.
I really need to get a new full exhaust soon and the experience fitting that will be worth doing over having it fitted at a garage.


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Exhaust manifolds can be a pain, What is main problem is poor quality bolts put on in the factory, extreme heat and corrosion over the years, impact wrenches are great for changing wheels, but can rip the head of the bolt if its corroded in!! I see that you have two choices, either a blow torch ( narrow flame) or to shock the head with an hammer with plenty of penetrating oil and keep turning the bolt head a little at a time, failing that you will have to drill the heads of one at a time removing the manifold and exposing just the studs, you can then try to remove the studs with the same procedure as above ( as the stress of the manifold will be off the studs. I recently had to do similar to my pet suzuki ignis. when you replace the bolts go to industrial supplies and get 12.9 strength🤫 bolts these will never cause you any further problems provided you coat with copper or aluminium grease first!
 
My plan of action is to split the nut get it off and then use double nut method to try and remove the stud and they still have decent threads.
If it needs renewing it will get replaced.
I have copper flashed exhaust manifold bolts not sure how strong they are but I'm sure I will find out when I try my method of removal.
Once the seized on has been removed I think would be sufficient space to try this.
And at best there are 2 that need this doing.
As a last resort a stud removal tool could also be used.
Heating them up was my first thought but putting a flame to the manifold right next to the engine seems to have an element of danger to it.
Maybe okay if I can get the flame to sit at a small size but it was really jumpy last time and I decided it was probably best to not put myself in danger along with the car.
Safety first is very important because the car is stood next to the house and is a lot if other vehicles in close proximity...
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This is what I'm looking at in more detail from manifold to exhaust back box end.
The plan is remove the manifold drill to install the heat-shield i originally bought should been straight forward simple task.
then the problem area is in the centre-section as you can see in the photos its pretty much nackard and my guess is its blowing at this part.
there is a terrible amount of rust forming on the driveway at the rear back box exit but this was also a little in the centre section also before i dropped it to put gear shifter mech in.
the gasket on this area is not present as i bought incorrect part that i now have correct ring gaskets most of the fixing i will already have including gasket for manifold etc.
i really want to move from the manifold back and not buy everything at once in the hope i can find the area that was causing the pupping sound when The temp is up after idle (most likely the centre-section) That I'm looking at getting soon as these are pretty standard.

Going to ignore the front pipe for now change the mid and ignore the back-box to see if the sound cures.
Then later try to add/find a back-box that does not sweep down at the rear as this is not very nice looking.

All of my photos of this and other items for the car are mixed up on the blog and on the pc so im going to show all the ones i think are important here in one place.

Something to note is that the engine was replaced 2008 engine
So most of the parts should be easy enough to remove. As the vehicle does not get driven much if any at all. But does get started everyday and other than the pupping sound after warming up there are little other issues that i can spot myself.
the engine its self has of around 100k miles slightly above. On the clock its showing Orignal engine mileage of slightly more the 113k ish engine was installed at 80k this is what i was told and the only thing showing is that of a slip for the engine year mileage etc.
service history isn't much so I'm trying my best to give new life where the Micra has been neglected this being one of the main areas i think needs to be cleared up because the cat if original will be on end of life or if it was renewed that i doubt it may have a few thousand miles left in it according to haynes manual advice on cats. (i don't plan on renewing this tho) Possibly tho if it does last me a few years more.

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Looking closer at the center exhaust silencer.
Have just noticed that it does blow at every few moments a tiny amount hardly noticeable if you don't pay close attention.
Its at the bottom slightly inward of the end by about an inch or two maybe.
Below I can clearly see there is a drip spot on the floor.
Just wondering now if I should bother trying to block the hole or just get new part.
I was originally thinking it was at other side or on the connecting pipe at the back of the silencer.
I do have some fire cement for sealing chimneys on cast iron boilers or something like that so could test it out and see if it stops the stance sounds I keep getting after warming up.
Not sure if that would stick to or seal on the area I have now identified.

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Okay i had a look and tried to cover it up with the cement it felt as though it caved in so now is a bigger hole that i suspected a pin hole size or so.
have just made order for a centre silencer.
The area that has the rust on it was where it was blowing it was rusted right through from inside out.
 
Hi, just been reviewing your progress, I think looking at the manifold the bolts are in pretty good shape compared to some, If the manifold is not blowing , I would leave this and concentrate on the rest which looks to be about ready for ripping out, I will also give you a little advice I gave to previous member who had a noise problem and that is starting cold engines for a short while can fill your new exhaust full of condensation (hot gasses on cold steel ) and if you don't get the system up to temperature and then leave the car stored again eventually over time internal corrosion and exhaust pressure will rust your new system from the inside out!! It is also bad for the cat on petrol engines.:oops:
 
Thank you for the helpful advice,I'm getting the part in a few days and am going to remove the back box and tidy up the flanges in the hope that it can be reused for a few extra months then I'm going to replace that part with new.
I can see how they don't like standing and not being used.
It does look like a whole renewal is going to have to happen from just after manifold down pipe.
I will do my best to make sure it will pass its next MOT but cannot see the back box lasting much longer if it even survives being removed.

Edit :- Here is a short video showing how the bolts are installed in opposite directions.
Not sure why this would be and if I can install them the way I want the nuts will be facing towards the rear of the car..

Will raise it up a bit tomorrow. Probably start to dismantle the rear section. Locate rust, removal,free up the bolts and probably have a look at the overall condition of the back box. In the places that I'm unable to see while its installed on the vehicle.
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I can see why you would be wondering why two of the flange bolts face opposite directions, one is that pressure is applied at different sides a) stops both bolts vibrating loose in same direction, and b) can be bolted evenly at the same time using two socket sets!!
Try a exhaust bandage for now. once you a full system in place that will be one problem of your list, refurbishing k12's will be worth it as they as much fun as my old mini to drive.:giggle:
 
Just got the mid silence today.
Box was damaged.
Opened it up and its got a dent and a few scrapes.
Meanwhile removed all that needs to be taken off.
Chew on removing back box last resort was cut the pipe off.
After that I got the bolt out with rattle gun.
So far I have reinstalled the new part after draining the tank.
Or is it a back box full and I mean full of water like its been filled with a hose pipe
Any how I think I need to tighten the center section more as my right arm has little torque after all the cutting and chewing on.
Its slightly blowing I think might be a few turns to go on one or both bolts.
Will take some photos later on if get chance.
For now he is a pic of the dents and other things I did not order..
Car parts4less normally are good with sending items.this time though I'm going to have to send them the photos because dents and scratched and damage.
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Had to loosen it back off and remove the ring it was all bent and didn't seat properly.
All done and dusted.
The pupping sound was water and now it's gone sounds like a different car I will definitely be swapping the back box next as this should not be too much trouble next time.
Its not as easy as it looks but its worth the effort for anyone else who needs to replace an exhaust part.. The backbox drain hole was blocked a quick bit of drilling let a lot of the water go. the old unit was a bosal center and backbox.shame i didnt drill it out last year because it might have saved me for having to renew the exhaust so soon.
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If you can get a small can of exhaust paint and paint round the flanges of the new box as the parts are galvanized and THEN welded together leaving the round ring of weld you can see on the new exhaust part, this is the first to start rusting and painting this will help seal from rust starting. I know when you start out buying various tools etc can be a bind but the tool you buy now to do the jobs you want to do would have been lost in garage bills!
I say this because when I first got my k12, the garage quoted me £98 for a simple oil change. I did this myself for £18 oil and filter. see the money that I would have lost to the garage!!!!!!:unsure:
 
Have added some liquid gasket sealing paste to the flange and put the whole tube or what was left of it on then when tightening I've sealed the flange round the circumference to keep out water and slow down the corrosion in future.
I would have liked to have painted the whole exhaust before install but the tin I have only has a tiny bit left in.
I really need to buy more sealing gasket paste to put at the muffler back box flange but I'm going to wait until I replace it so its clean and easy to work with.
Today I've been clearing all the rust away that the drive has been covered with at both the front and rear.
Warmed up the car again today and am not experiencing zero pupping,and it sounds to be sealed with no leeks present as far as I'm aware and no strange smells while Sitting with both windows fully down.

My cost for this so far was 33 for the silencer and about 20 ish or so extra for the parts not sure exactly but 98 pounds is a price the silencer is listed as probably meaning that would be the price minus fitting.so I know that I have saved a little and gained a lot of knowledge in the process and this to me is worth every penny because I'm learning.

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we all keep learning something no matter how long we have been doing it !!! just keep up doing what you are doing it will become easier as you gain experience (and TOOLS!!)(y)
 
Just got the new back box and since I can't find anything suitably priced I've matched with another klarius part. So I'm going to be running pretty much a standard exhaust
Only thing is the exhaust paste sealer is missing.
The biggest disappointment is I can't fit it while the road is getting relayed because its very dusty etc.
Not the type of environment I want to work under the vehicle in.
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Yes I know the problem, been working on my pet ignis, and cannot remove outer CV joint, going to have to cut it in 2 and open it up like a clam shell!! to get it off. similar problem near me with road cutting grinding going on. left mine to another day. Try checking the inside diameter of your exhaust pipe, you may be able to get a tapered sealing ring to fit and it will be universal so wont cost much, I find these best and as you tighten the seal gets tighter.:unsure:
 
I had the proper rings for the pipe the one at the rear fit snug and the front one did not seat so got crushed on one area and seemed to be unusable again HAG3 as in the diagram just a different number for the Klarius branded one.
Was wanting to replace the bolts in the centre section but they would not seem to remove from the down pipe.
The idea was going to be to add the missing springs to the longer bolts i have and then it would have been all new to the down pipe.
Plus the springs that should be in that area would give the pipes a little bit of flex movement rather than only the rubbers on the hangers.
Will try to get another one of these and tap it on as they are cheap enough.
That way can try again at bolt and add springs if they will remove.
 
This is the exhaust paste it was really cheap for this since the last one I bought was 30ml and was more expensive I was going to get the klarius one bit this will do the same.
300ml for less than 3 quid and its more than I will ever need in a life time probably.
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Hope it works for you, and you never know if you need it in the future, I have a garage full of part used items, some times they come in useful when you least expect them. I ordered a new drive shaft today as the splines are really chewed up, so what i mean is we all keep getting challenged with various problems, but better than new cars of which I have had many and I don't think they are worth it today.(y)
 
Testing out fitting the sealing ring on the flange that I cut off giving me the correct pipe size to get the curve I want.
So far I can now get the crushed ring over the pipe and it sits flatter now than it did on the new pipe.
I'm also hammering out a short metal ring that is solid so won't crush like the originals.
Downside to this after making and thinking about it.
Might rust quickly,Slight gap with no welding..
Does not seat as flat as I would like.
Was worth a try and didn't take long could make more easy.
If was able to weld it might work good unsure.
Other than that buy new ones.
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you have two options, one is to order a cone sealing washer, put this code into e-bay and you will see what I mean: 44022AA123 , make sure you get the right inside diameter correct. Or you can get some heat resistant gasket paper and draw round the flange shape onto the gasket paper, cut it out and fix it between the two flanges with a little exhaust paste.:unsure:
 
You are showing me the manifold ring gasket I have a spare one of this along with a new manifold gasket That I'm not working on ATM.
MZG28AB 410429 (klarius) part number. Those are much thicker than the centre to down pipe / backbox exhaust ring gaskets

The part I'm showing here is the downpipe to centre silencer Its just a metal ring like in the photo above
HAG3AW 410156 This is what (eurocarparts) shows but there are no sign of them now on the site or any of the fixing for that matter..
The exhaust system has no second cat and the car is euro 3 not euro 4

In short after a couple searches it seems that the part is not correct. I always use the (Your reg part) On the site to find correct part. But somehow they had it listed 05 or whatever compatible and today when I search it says its for 2010 onwards.
So have asked them about this.
712600681Klarius Exhaust Gasket/ SealNissan Micra 1.2 2005
Those are the details showing but if searched its now 2010 its for just the rear backbox...

That is interesting because the flanged style gasket (Way Oversized) I purchased first was for a Ford C max when I got that is what the packet said and these items all been Klarius
Maybe its just my exhaust system or this company has serious errors in part number listings.

Edit :- Backbox had one of the gasket rings intact and downpipe to centre did not unless I missed it and its still in place unsure.
I found after a couple searches a replacement alternative that should be okay.
Thank you very much for your help its always welcome.
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This is what I'm wanting to find out since the bolts are really short I could not just add springs to them. (Down pipe to middle silencer )
I do have longer Bolts.
Need to figure out how to remove these short ones first.
From what I've seen so far they are partially threaded. For the spring and the thread is not as wide diameter than the spring side.
Trying to figure out something that will work for this. Flex in the exhaust seems to be important.
Unsure really if I should just stick to how it was already.
I'm trying to find something similar to this bolt spring combo.
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This is the original idea I had in mind. The only difference is that the bolt does not have the flange to bottom out on.
And with the springs I have spare. From the manifold area, Being rather oversized for the bolts. Would need some bigger washers to hold them.
I don't really want to use the bolts again from that part but those are more likely to be something that resembles those in the last post picture.
Without the flange that is wider.
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Time to list some part numbers for this they are listed as 20020A Bolt
I am trying to identify what the last two are with regards to placement on the exhaust as its not showing in the diagram
(20606-1U60B) this part looks like it would fit to the downpipe/centre section..
I am going to try to if its not too much add the spring bit to the centre part and ignore the backbox one because this end i was happy with my set up so far with the old box installed.
I'm using nissan4u catalogue. And have just noticed that there are different part numbers for each of the gaskets.
I was originally under the impression that they would all be the same.
This may now explain why im having trouble with that part fitting correctly
(20606-8H30A)
https://www.buycarparts.co.uk/oen/206068h30a

(20606-8H30A)

(20606-1U60B)
 
You may have to fabricate a hybrid system for your needs, you can get "shoulder bolts" in the thread size you want and with the length you want, then buy the springs on length and size to fit over the shoulder bolts, Like with all older vehicles I tend to make my own systems as off the shelf tends not to be the result I am looking for or are too expensive. You seem to have a good idea of what is needed for your system, there are lots of engineering solutions that can sort you out and car spares sometimes do not do it, that's why get an idea for what you want to do and check other sources as well.:unsure:





y
 
Great thank you something as simple as the name shoulder bolt will help a lot,As I did not have a word or name for the item.
Measurements will be equally important and I will try my best to find a suitable item.

Edit :- After some measurements.
This is what is reqiired.
Up to 70mm length bolt M10 (No longer but can be slightly shorter down to 60mm) this was measured for the longer springs I have so can be shorter to 60mm
Around 22 mm compression springs.
Asking about the springs set of 6 I need more info regarding dimensions of these.

Parts I'm looking at now are
EBay searches :-

Compression spring (6 pack) DIY 4.99

M10 A2 STAINLESS PART THREADED BOLT SCREW + FULL NUT & WASHERS HEXAGON HEX HEAD
4.99
This is much cheaper hope this helps others also.

For now I'm getting the bolt kit and will then decide spring size once I get a better idea.


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Great that things are working out, yes it can be frustrating when you have ideas in your mind about what you want to do but are hindered by terminology, great that this site is there to try and help others.;)
 
Okay so I've put back box on and the sound is excellent now. All went smoothly.
Now I'm working on the silencer downpipe flange...
Tried tapping it out with hammer these bolts are rusted on.
They won't move and I wanted to renew the whole bolt set.
Anyhow I can't seem to get a socket onto the bolt and its hard to see I had to take ea photo.
Would like to know if anything what should I try next time.
Have now taken it off the jack and axle stands.
So far I'm happy with the result.
Still waiting to decide what springs I should get.
The manifold one worked perfectly with the bolts I got recently for the back box.
This is what I'm looking at downpipe flange to silencer flange rusted on badly bolt cannot get socket on..
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try spraying penetrating oil in the thread you can see, wait a day and do the same if you are not in a rush, try a small blow torch to heat the part up if you can do it safely. be aware that the heads of the bolts may be corroded with water and exhaust heat and may have lost their hexagonal head!! I had this earlier in the year and ground the heads off and drilled out the studs, but try the penetrating oil and heat first, use some mole grips if you can get them on. First try to tighten the bolts only slightly this will hopefully break the rust lock and then try to undo. like with all things try not to rush this take your time and it may work then you can replace with stainless steel. for the life of me I cannot understand why they still keep putting rubbish bolts on exhaust systems, the pennies they save it stupid in the long run.:unsure:
 
Thank you for your reply i will try to remove the rust was thinking how to do it but can only see blind then anbit with the camera from the side.
The problem is i have the car facing the other way and i think It was more comfortable to work under in the other direction.
As using my right hand and being left handed makes it quite tough to work with.
I do think that will work what your saying because the rust is really not moving as I very lightly tap the threaded side of the bolt this is not threaded for about a cm down so I cannot damage the thread.
Then I was tapping the bolt hex end with right hand and it was not really getting a good tap even.
Did not see any rust falling away. I did however spray the hex side greatly and then the threaded side before trying again.
one thing i can see is that my M10 flanged Nuts with the socket on think its 17mm is not a good fit between the flange as when it gets so far its going to foul on the flange its self so will be hard to fully tighten that up.

For now I'm going to let it be for a few days till these road cushions are installed, Get some fuel so we can see if its good when driving.
And I'm being extra careful not to destroy the flange of the down pipe because this I don't plan to renew as I'm sure its worthy of a few more miles yet.
Not sure what I can use instead of the M10 flange nuts. As neither those or the flat sided ones looked like they would tighter properly.
Just going to put a nut on both sides of those bolts, Tighten them down then add springs later. As I think that would be good to get the hard part out of the way first.
Made video of the start up with backbox exhaust fitted its got a lot of echo..
Cause just using phone And its really close to a wall..

Will upload link here later on >
<
 
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Try some "long nuts" on the flange, this will keep the socket from fouling the flange skirt:://www.ebay.co.uk/itm/HIGH-HEX-CONNECTION-NUTS-HEXAGON-CONNECTOR-CONNECTING-ROD-BAR-STUD-LONG-NUT-ZINC/124262543604?hash=item1cee9ff0f4:g:pG0AAOSwShtcmjkN:unsure:
 
Just looking to see what cost is to renew the whole part.
Those would work and thanks for helping me on this one.
I should really just swap it out like the rest cause it will eventually push rust into the new sections I've fitted.
Do prefer to re use as much as possible.
It will remove rather more easy and be replaced than faffin about with it.
Then the question would be about swap or renew the lambada sensor. (Was thinking might help with fuel economy) unsure tho.
With regards to the nuts on the part. I think they seem an odd thread size with hex size lower than expected for an M10 thread or from what I've seen so far that is.
Oh yea and the bolt rusted only I can remove the nuts easy without problems.

Something I was looking at today.

Rear bumper has a crack at that GB sign it was stuck on to hide the crack so I'm gonna have to either learn to repair bumpers live with it or try and replace at a later date.
Probably go with a sport bumper if find one on KY0 G Silver.
Was trying to see how its fitted because I originally wanted to cut a shape to add an exhaust tip maybe.

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Sports bumper would be ok, repairing polypropylene bumpers is a specialist job to get the job done right there are stresses in the bumper, you can try a thick piece of plastic on the inside and hot weld it to the inside if you need to, bolts sizes on hex head sizes come in different sizes dependent on manufacturers, some times a 16 mm or 15 mm head can be found on bolts that should take a 17 mm hex head, and occasionally imperial bolts can be found also as imperial fine (unf) look similar to metric. I my self use impact sockets (lot tougher) with a range from 8 mm- 24 mm going up in 1 mm increments with out missing any sizes as jap cars tend to be 12, 14, 15 16 and 18 on some of their parts.:unsure:
 
Hi, you will be looking for the sports rear bumper, try this part no: 85022BC440. this will help with your search, and don't let the scrapyards rip you off, check out new one's which include free shipping! the sports front suspension is very good when in good condition, but can get a bit finicky as they wear, the springs are the one to watch they are highly sprung and prone to snapping when they get older and put under stress!:unsure:
 
I always get my items delivered it cost slightly more but I'm unable to travel till I pass my test.
This is on hold for a while.
Might be able to get another item next month if I'm lucky.
Middlesbrough is really close by tho and that is a huge saving on what I'm finding.
Thank you for the great info.

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This is an option i thought would save me a few quid doubt i would get that sort of finish would have to look to see if the plastic is all present as if some is missing it would make this pointless that and I'm not so great with the spray can.
Would have to remove the GB sign and im not sure if that has to be present or not I'm guess it needs to be displayed.

 
If you are not in a rush I personally would wait and keep an eye on the market for one to pop up in the colour of your choice.;)
 
Will show the bumper damage tomorrow.
Its not too bad I don't think.
I'm unsure if I want to update it with sport bumper yet as I keep thinking how the k11's look at the front and they have a similar style the rear however I'm not that fussy on version.
Also something else I would have to contend with on this one is the sensors. (Reversing sensor)
If its not a big job I'm going to repair for now and see if I'm any good at fixing them like this is the closest I can find similar type damage maybe a little more extreme tho.
Been quite busy today as trying to get another interview if I'm successful will probably not be here much.
The project will definitely continue tho either way..


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standard bumper is: 85022 AX640, about £55 brand new ith free delivery if you decide after the repair that you are not happy with the results.:unsure:
 
This is just above exhaust must be a common area cause I seen one cracked in this area before.
I didn't remove sticker in case it all falls out and looks worse.
It feels like all the plastic is still behind it.
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Any repair would have to be from the inside so if you do take off the bumper, make sure you have all you need to do the repair and then you are not stuck in limbo with the part off and not able to complete, when these are manufactured stresses in the plastic are there in certain places and generally this is a typical area that splits if it is knocked, they could use ABS for the bumper or polycarbonate, as these are impact resistant but because the material is more expensive they don't use it. If you intend to repair I would try chamfering the inside of the crack and using a glue gun and quality glue sticks run a bead of this all along the effected area, and if you can get some polypropylene sheets cut these in to strips and glue them on too. this only a quick repair and if it holds you have the same bumper with the rear sensors and no worrying about colour change.:unsure:
 
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