[ViperGRM]

Hi folks,

I recently acquired this Mazda 6 2.2D and it seems the EGR valve probably needs a good cleaning. I bought some EGR cleaner and I've removed the exhaust which I believe goes from the EGR valve to the intake manifold. It actually wasn't bad at all. I didn't dismantle anything else because I wasn't sure what to remove next. Is there a guide somewhere on how to properly remove the EGR valve and give it a good cleaning? I couldn;t find one on YouTube. Only a few for the old Mazda 6 I think, but it's a different engine. The EML code it is throwing up is P0401. Thanks all!

 

[Wooly]

Interesting to hear this, I bought a 2014 Mazda6 2.2D, around the same time, shortly coming out of the garage, engine inspection warning, turns out, its EGR, Garage wanted it for 2 hours, 3 days later its still in the garage, so, is this a common fault to expect in this car I wonder? hope not..

 

[ViperGRM]

Not sure how common this is. I left mine in to a local garage and they tested the EGR valve. It seemed good, so the cleaned it out but that didn't sort the problem. I've had the car about a month now and the light is still on, but I don't experience any symptoms whatsoever. The car drives great and isn't right at idle etc. I'm going to clean out the throttle body to see if that helps. Not sure where to go after that.

I'm guessing yours isn't the EGR valve either, which is why it's probably taking so long for the garage to work out where the problem is. Let me know when you get yours sorted if you don't mind. We could have a similar issue. Hope you get it sorted soon!

 

[Wooly]

you could be right, I will definitely let you know. Fingers crossed, might get a little more economy from it, I was hoping for more than 45!! but hey ho, I am liking the car

 

[Wooly]

Got my car back last night, after they replaced the EGR Cooler. no warnings, well, at least for 50 miles until I got home, then it came back on, so, I will be calling the garage shortly!!

 

[Jay at]

Okay folks we sell used cars in Birmingham and we had some problems with a Mazda 6 2.2 diesel.Dpf light on,traction light on,eml on.4 workshops later no solution. Went to Mazda dealer we deal with who said we know what it Is.Clean the inlet manifold.Firstly the MAP (manifold absolute pressure)was coked up and was cleaned.It is one bolt and easily accessible.This improved the mileage we did to 150 but still came on.Now it’s manifold is stripped down and has a lot of carbon.Our fault was indicating MAF but you should interpret as MAP/MAF.We are having the manifold decoked this week and road testing again.I know your fault code isn’t the same but a blockage further upstream could restrict the egr valve.Our egr was cleanish but the MAP sensor clogged as was the manifold.If anybody is interested I can post the results after the manifold is cleaned.MAP sensor clean made a lot of difference to the drive for 10 minutes work.Unfortunately Diesel engines after 50k miles will accumulate carbon enough to affect performance on the air intake side even if no lights come on.An egr clean on an Audi A4 2008 felt like a new engine.I hope this post helps

 

[ViperGRM]

Thanks for that. Yes it would be interesting to see the outcome of this. For the record, mine seems to be intermittent now. It will come on/off every few days or so. A faulty sensor maybe? I just got a replacement EGR valve and will maybe swap it out to see if it makes any difference.

In addition to this, another fault has appeared - P258B (vacuum pump). I've left it in to 3 or 4 garages so far and no one has been able to diagnose it. It's so frustrating. I've also bought a replacement vacuum pump to swap out. A side from all this, the car is driving fine. I've had tne engine carbon cleaned as well. If the warning lights didn't come on, no one would know any different.

 

[Jay at]

Okay Viper,the garage may finish the cleaning today and we will road test it and I can update you.Are you talking about the brake vacuum pump.The manifold pressure I believe affects the brake master cylinder.Clean your MAP sensor very gently with Holts carburettor cleaner £5.Avoid the centre prog.Get a picture off the internet to see what it should look like and use a strong pin to dislodge carbon as well.The ECU will for a millisecond register atmospheric pressure just before pistons work when you switch on.I am not sure if a blocked MAP sensor can confuse the ECU into throwing up weird codes as it doesn’t think atmospheric pressure is a fault.Once engine is on the MAP sends a signal as to the pressure change and adjusts the air flow.I am not a mechanic but this problem has made me research loads.There is Justanswer on google where Mazda technicians advise but they charge (10-15 quid).Its a live chat.

 

[ViperGRM]

Thank you Jay. That is incredibly helpful. Yes it is the brake vacuum pump. I already have a few cans of the carb cleaner. I'll hopefully get a chance later today to try it.

My mechanic skills are somewhat lacking though! Finding it is step 1 . I'll let you know how it goes. Do you think this is causing the P0401 EGR fault as well or should I just swap out the EGR valve? I can just about manage that. Thanks!

 

[Jay at]

Viper chap just clean the sensor first as it’s so easy and it may sort out something.Changing the EGR if you’re unlucky could result in another problem but doubtful.Remember the MAP sensor has influence over your EGR.If your MAP is clogged then the EGR will have plenty too.Reading into things it is a routine maintenance which ideally should be done.Try the MAP first 20 mins and road test.Then do your EGR.Have you an OBD diagnostic machine to clear codes?
Youtube have plenty of videos,study them first to get a good understanding and build up your confidence.
A good clean will benefit any diesel car with 30k+ mileage.Give it a go

 

[Jay at]

 

[Jay at]

This MAP was cleaned and the engine transformed.Better response,better MPG,better braking.Also give your Mass air flow sensor a clean (electric contact cleaner).Another easy one.We thought the car ran well until we cleaned the MAP.Some times these slow build ups just become normal and we know no better.

 

[ViperGRM]

Thanks again Jay! I will most certainly do that. Yes, I have a Bluetooth ODB reader and also Forscan with an ODB cable Hi Lo switch. There's an option in Forscan to re-initialise the EGR valve so I would assume that needs done if I swap out the EGR valve. One thing I just thought of. Quite often when i switch the engine on, it will start at higher revs (around 1,000-1,200) before settling down at normal idle. I wonder is the dirty MAP sensor causing this as well.

Thanks!

 

[Jay at]

Copied this from internet.
‘It is normal for the engine rpm to go up to about 1200 to 1400 rpm when first started and then comes down gradually. This is for emissions during cold start and considered normal. If you feel it is not normal then I would recommend having the computer tested for stored codes and if no codes then you may have a sticking throttle body when cold.’
If your MAP isn’t registering correctly I would hazard a guess it could affect the revs.Your MAP determines your fuel mixture is correct and not too rich or lean.

 

[ViperGRM]

Any idea where the MAP sensor is located on a 2.2 GJ engine? I thought it was at the front right of the engine, according to the limited information I can find, but I don't see it. No doubt it is staring me right in the face

I just noticed this at the front of the engine. It looks like something is corroded or cut, but it may not be in use. I'm not sure what this is...

 

[Jay at]

If you look just above the alternator its got one bolt and electrical connector.Rotate first clockwise and anti-clockwise and then wiggle out.It has a rubber ring so will give a little resistance.

 

[ViperGRM]

Fantastic. Thank you! I'll take it off later and give it a good clean. I'll also clean the MAF sensor.

 

[Jay at]

I am not sure what the unit but looks like a bit of corrosion on external surface.Try and identify it but looks like a light clean job.You get back to it later.

 

[Jay at]

Actually you can see a cut cable,I will have a look tomorrow and see what it is.

 

[ViperGRM]

Thanks Jay! Yeah it looks like a cable or somerhing but I'm not totally sure what it is.

I've literally just removed the MAP sensor and it looks well clogged up to me. I have the MAF sensor off too. Just giving them a good clean now. Hopefully this will make a difference