I have read the vacuum pump may be a Mazda recall.See how you get on.

 

We haven’t had time to collect from the garage as of yet but the mechanic says road test 45 mins showed no codes.We had 6 Mazdas in stock and sold 2 over the weekend.I read the recall but it was the Daily Mail Australia.Different countries have different engine software.Recently Mazda UK were recalling for shutter valve software (September 2019).
They do notify you by letter.Best of luck Viper if you have any issues I am interested so don’t hesitate to post 👍.
Juddering can be so many things but if it’s slight It can even be the road surface etc

 

Thanks Jay. I plugged the ODB tool and it did show a pending error again for the EGR code P0401, so it's probably still there. I guess it will need a proper clean out. No vacuum error code yet though. Either way, that MAP sensor definitely needed a good cleaning out. There's no way it could have been functioning like that!

I'll keep you updated.

P. S It's good to see a garage making a good effort to make sure their cars are running well. There's far too many who don't bother.

 

Use Wynns EGR cleaner for diesel engines as the soot is different between petrol and diesel.I think a pending error will have to trip 3 times before it registers.Hopefully your vacuum doesn’t light up.We tested the car and the traction light came on even though it drove really well.Its going to Mazda dealer for their diagnostic checks.The first check is £70.After that your charged until they get a definitive cause.Waiting to see where we go with this one.Will update accordingly 😀.
It was all good for 100 miles.

 

Same thing here. Both lights are now back on again but the car is driving perfectly fine. I might just swap out the EGR valve to see if it makes any difference as its only a 10 minute job, then I'll consider taking everything apart to give it a good clean.

Check the connecting pipes for soot when you do the work 👍

I also have a vacuump test kit which will check pipes for leaks etc but I've no idea how to use it lol. I guess I'll fijd something on Youtube which shows how to test propely. I'll keep you posted

 

Check the connecting pipes for soot when you do the work 👍

 

Mazda have checked the car and say that the EGR cooler needs to be changed as they believe it is sooted up.They only replace the part as they cannot guarantee a cleaning process.Part at £550 plus labour comes to £900+ ouch!
We had the manifold and shutter valve previously done plus EGR cleaned by different garage.
What we have learned is if this works then Mazda got it right as their mechanic said it’s standard for his workshop.They use walnut shells to decarb the manifold but with the cooler they can’t tell if it’s effective and can’t guarantee the job as they can’t see the results.I accept that as good practise.
The garage who removed the manifold say they will clean the cooler chemically for free.They will get a new cooler weight and compare when cleaning.Plus try blowing into the cooler originally and see if it improves.Well we are grateful for their good will (15 year business relationship) so will give it a try and update.
Also apparently the traction light coming on is a red herring and just an indicator something is wrong before the EML and DPF comes on.THAT IS WEIRD.Carbon build can throw loads of fault codes up.Strangely we are enjoying this even after the money we have thrown at it.The Mazda team were great

 

The EGR cooler has been removed.The battery,battery base and air filter box removed.Some coolant also and apparently it’s quiet straight forward.The black bracket was in the way but plenty of space after removal. Its a straight forward removal.They have used two cans of egr and carburettor cleaner and soaked it overnight.
They used an air line to blow both sides of egr first and it was like a dirty exhaust.The end that you can see through was badly soothed and 25% blocked.Tomorrow they will half Empty and thoroughly shake and air line it again etc and look to see if air flow has increased.They have done it before and reckon it will work.
The EGR Cooler cleaning company in Pontefract use ultrasonics claiming 99.5% Carbon removal for £89+vat and 24hr turn around.We didn’t want to spend time parcelling etc so is our back up plan.
Terraclean Birmingham said they didn’t believe they could shift a blockage in the cooler but did say all sorts of codes come with a bad cooler and to look at the whole system as a whole regards EGR faults including DPF.Will send cleaning pictures tomorrow.
Now I physically saw the cooler (forgot to photo) and it was not a pretty sight.Now it was Mazda York who originally told us to clean the manifold but from the pictures he should me I recall they had took out the cooler as well Which is not needed for manifold removal.
They were familiar with this problem and have dealt with it many times before.However all EGR have this problem.More updates coming 👍

 

The The

 

The EGR pipe was left on to create height and the cooler filled to where visible on the left hand side (inlet).Both holes were taped overnight to prevent evaporation.
Well lots of carbon was removed.When emptied air line used to blow the channels.Cooler is now fitted and we will test drive again 🤔

 

That's really interesting how the cleaning process works. I live in Northern Ireland otherwise I would seriously consider getting it properly cleaned out from one of those places you mentioned. I could almost be sure that this is the cause of my EGR fault. Like I say, I am going to swap out the EGR valve purely because it is staightforward enough to do compared to taking the engine apart to clean it.

Regarding the vacuum pump code - P258B, I am beginning to think that the puimp is faulty. Today when going down a hill I decided to intermittently press the brake pedal. After a few presses, the brake pedal stiffened up and had little effect on the brakes. The car would still slow down but nowhere near as fast as it normally should.

 

Yes they have been an issue.You should be able to test it first,I’ll do a bit of research later.
Your engine has an EGR bypass valve as well connected by the long steel pipe to the EGR valve which also lowers emissions,you could clean that as well.It was something that Mazda asked if we had done.It is used when you start the engine and allows engine to reach optimal temperature faster.
“EGR bypass valve – Located on the intake inlet. The ECM uses this valve to allow exhaust gas into the engine without going through the EGR cooler (EGR cooler bypass). ... NOTE: The EGR bypass valve is cooled by engine coolant. ECM Control. The EGR valve and the EGR bypass valve are both electronically controlled by the ECM ...“

 

I swapped out the EGR valve today and took the car for a test drive. It was driving absolutely fine as ever but unfortunately the P0401 error code popped up again. I didn't think it was the EGR valve anyway but at least we now know for sure that it isn't. I think the best thing to do now is as you suggested. A proper clean of the whole EGR system. There was plenty of carbom laying in the EGR valve and the connecting ports etc. I'm really not sure what else it could be.

I had a look at the vacuum pump and it looks a little more complicated than I'm comfortable with. I'll ask a local mechanic to do it as he'll do a far better job than I would. I'll ask him about the best way to go about doing a proper EGR system clean too.

 

Okay Viper we believe we have maybe finally resolved the problem.Firstly after cleaning the cooler we test drove and at about 80 miles lights came just as before at about 80 miles motorway.Then we got really angry and took an EGR cooler out of a perfectly good car and tested that.Well 120 miles later no lights.Tomorrow night were going test it again to 174 miles.I believe it was the EGR COOLER as Mazda had said!
It makes sense as a blockage will throw all the air values out.All the sensors are giving information to the ECU and it’s trying to it’s hardest to compensate by making adjustments to EGR valve etc etc
What doesn’t help is fake codes.The ECU sensed a blockage which normally would be the DPF and your supposed to drive for 15 minutes once blue light came on.The sensors in the exhaust system are designed to detect reduced gas flow which is what happens when the gases are restricted at the cooler.On a long run it senses this restricted flow and warns of DPF soot accumulation,we had already changed the DPF previously.
Tomorrow we will know for sure but I am 99%
Now let’s sort you out Viper.Firstly you can post your EGR cooler to Pontefract and they will clean it within 24 hours (01977 600630) and return.Their website explains everything and we are sending our bad cooler to them next week and testing driving it.The video site I posted shows you exactly how to remove it and our mechanic did ours in half hour as it was his second go.If you want to go that route there a couple of things I think will help.
However it’s late now so allow me the weekend to get my head around your p0401 gremlin 👍

 

Excellent! Fingers crossed you've got to the bottom of it. It's so difficult to troubleshoot these things.

I wonder is the EGR cooler the cause of my woes too? I had the engine hydrogen cleaned for the same price but I am still seeing a lot of carbon in it.

 

@Jay at Would you happen to have the part number handy for the EGR Cooler? I think it's the same engine as yours. There's a few on Ebay for around 60 quid so I'm thinking maybe it's worth a shot rather than sending off the EGR Cooler in the post. Thanks.

 

Our part number SHO1 20 30Y MARAYASU INDUSTRIES CO.LTD
Viper what is your car exactly,age,mileage,service history.I used to be a domestic gas engineer and familiar with combustion and flues which is similar to what we are dealing with.Where ever we have a carbon restriction be it in the EGR cooler,EGR valve,manifold,DPF it will be sensed by the car.Your code p0401 is insufficient air flow.Ideally the cooler and manifold should be cleaned and the EGR BYPASS pipe inspected and cleaned as well.It could well be accumulative effect of all these items.The manifold clean is a bit more difficult.The problem with a used part is you can’t tell how much clogagge you have,how many miles did the vehicle do.You can visually inspect it at one end and try and clean it as we did but we were not able to clean it properly so it was all done in vain and now have opted to send it it to the Egr cleaner company as we do not want to sell a problem car to a customer.Unknowingly we purchased this car from a main dealer part exchange and it presented the problem on the motorway.As we cleaned the manifold first we can only speculate whether just cleaning the cooler would of worked.
However a used cooler most probably didn’t have a fault showing but will to some degree have sootage.Spending £60 when proffessional clean is £89+vat and postage is for us the better option.The EGR cooler is the first place the gases go to and the channels small and I imagine prone to blocking.Mazda will not clean them,just replace.A cleaner cooler may increase the air flow enough to get rid of p0401.We don’t know until we try.Older cars did not have coolers as emissions were not as strict but the AA is reporting this problem across the board for diesel and petrol.
I think you got a chance but by cleaning the used one increase your odds of success.No waiting for postage etc
If it fails your next step is the manifold.
Done slowly it is not difficult especially with video which is looking to remove the manifold as well so certain stages can be skipped.
Were going to take it for a longer run for peace of mind.Update pending 😀

 

Thanks for the part number @Jay at

Mine is a 2014 2.2D Skyactive GJ engine code.

I've been seriously considering buying an ultrasonic cleaner. 6l ones on ebay for around £90. I imagine this place in Pontefract do something similar. I could use this to clean vaeious EGR parta amongst other things. I've watched a few videos on it and most people seem to think they do an excellent job. I'm not sure if the 6l version is big enough for the EGR Cooler but a 10l one is only a few pounds more.

 

Interesting I will have a look too.I will measure the cooler tomorrow tomorrow and send you a measurement.Your engine is the exact same.I saw some one use a suspended glass jar with a wood sander strapped to it do a good job. 👍

 

Great! Thanks. I'll order the cleaner based on the size of the cooler. No point ordering a 6l one if its too small. Cheers

 

I think I'm going to order the 10l one. It is virtually the same price as the 6l version and the question is always going to be in my mind that I should have go the bigger size. It looks like it's going to take a week or so to deliver. There was another version on Ebay which I could have got quicker but they don't deliver to Northern Ireland. Hopefully the EGR cooler isn't too difficult to remove!

 

It’s about 15” long as I had to measure the gap on the engine due to the part being already packaged.I am not sure if it will fit lengthwise or you can tip up it side ways.I can send you photos of taking the cooler off and you look at the video as well. 👍 The air box,battey and battery box are only 7 bolts,the rest is straight forward as video,but I can tell what to skip.If you do it on a Sunday I can help on a live chat.

 

Wow that's really helpful of you Jay. Much appreciated! I had the airbox and battery etc off already and it was straightforward. It was when I contemplated swapping out the vacuum pump. I've thought about it and I've decided to give it another go. I hate the hose clips and removing the hoses but I've ordered a couple of tools that should make it a lot easier. I may as well have another go seeing as I have to remove the battery /airbox etc anyway (to get at the EGR cooler).

I ordered the 10l ultrasonic cleaner and it's been dispatched already. Hopefully it will arrive later this week. If it all works out and does the job, I'd be more than happy to throw your EGR cooler into it at no cost (other than postage obviously). Its the least i can do considering all the help you've given me so far!

I wonder is there anything else other than the EGR valve and cooler l could easily throw in to the cleaner? I was thinking the MAP sensor as it's still a bit dirty but not sure if the water will damge it.

 

Thanks Viper I will consider your offer.But firstly back to the cooler,will it fit into your ultrasonic cleaner?
It is recommended that you either drop the coolant level in your car or catch it when you take the hoses off,our mechanics just dropped onto the splash guard underneath (Or a bit of both).You lose a kettle and a half as reservoir also drops.
The black bracket will be in the way of everything firstly.The hose on the bracket disconnect at connection on radiator.
Under the cooler are two sneaky nuts hiding behind the cable,they support two silver pipes running under the cooler.Remove those and then nuts to cooler and turn cooler over and you access plastic clips to get cable off.You can’t get to them otherwise without breaking them.
There is a little splash guard as well.You only need I think 8mm,10mm and twelve sockets.Note your gaskets,one of them on the cooler is silver colour and sticks to the the inlet pipe.
I looked at the vacuum pump and it seems to have stuff going to other parts.Get a video if you can,I understand why you have hesitated.
The cooler cleaning company won’t touch anything electrical.I filled a spray can lid with just enough carburettor cleaner spray to soak the dirty part of the MAP sensor for 15 mins and cleaned lightly twice.Just pick at with a pin and then everything dry out for 20 mins.
I will investigate the vacuum pump tomorrow.We don’t want to overreach unnecessarily and will speak to one our mechanic mates.Remember Viper if I mess up our mechanics are also mates and will sort us out in an emergency.
Do not want your car sitting on your driveway 😀

 

Actually only 3 bolts and a hose

 

Mazda CX-5 Service & Repair Manual - Vacuum Pump Removal/Installation - General

www.mcx5.org

 

Thanks alot for that by the way! I didn't know this was available online. I only have the downloaded PDF version. Very handy. Thanks!

If you compare to the video certain things can just be placed to one side without compromising access.Use a clear ziplock bag to collect coolant and you can put it back in.Your vacuum pump is fully exposed 👍

Thanks. I will make sure to have a bag to hand to catch the coolant. I would guess spraying a load of carbon into those bits that I can't remove would be advisable? I guess I may as well. Might help release some of the hard to reach carbon build up parts.

Read up on the vacuum pump and see if it’s a straight on off job.No resetting or anything else you need to wary of.

There's only 3 bolts holding the vacuum pump on and it looks relatively straightforward to swap out. It just needs tobe alligned properly. I should point out that the replacement I have is a used one which has been tested working. I would ideally like to replace the O-rings but I'm not sure if these can be bought seperately. Well, I haven't been able to find any yet.

The photos are extremely helpful Jay. Thanks again for taking the time to do all this! Really appreciate it

 

Thanks Jay! Yes, I wouldn't want it sitting in the driveway either

I actually have the proper service manual which has a guide on how to remove the cooler. I'll going to follow it as best I can. I'm not great at reading car manuals to be honest.

I don't know if the cooler will fit the ultrasonic cleaner yet until i try. If it doesn't I'll just have to do each end separately. Trial and error really!