2.2 diesel misfire or stutter.

[Jamesbil]

Hi all,
new here and hoping for some advice.

Recently purchased a 2014 Sport NAV AWD Diesel with 105k miles on the clock. Full Mazda history.

It has developed a stutter or misfire when cruising, not on acceleration. Kind of feels like dirty fuel but I had it serviced at Mazda and they have told me they have replaced the filter.
It is intermittent too, recently drove 70 miles, first 50 were fine then spluttering for the last 20. Same day it drove home the 70 miles fine.

Plugged it in to 3 different diagnostics, no codes.

Till the other day when the engine management light came on. Code was P0098, IAT2 Sensor high.
Removed the sensor, really dirty, cleaned it and cleared the code.

So far still seems to have the same symptoms.


Any ideas?

Thanks
James

[howardsathome]

Sounds all too familiar to me in May last year at 40,000 miles. Diagnosed as blocked MAP Sensor (measures vacuum pressure on inlet side of engine). Details in previous postings on this forum. Can't just locate at present, perhaps Administrator can help?
 

[Anchorman]

I’d run a tin of BG244 through it before you start any major surgery. It costs about £24 off Amazon and is amazing at clearing sticky injectors.  Add it to a full tank of fuel.

[Jamesbil]

I’d run a tin of BG244 through it before you start any major surgery. It costs about £24 off Amazon and is amazing at clearing sticky injectors.  Add it to a full tank of fuel.

Ive been using Dipetene which I've had good results with in my van.

[Jamesbil]

Update...

After taking the MAP/IAT2 sensor and cleaning it, was really caked, it has seemed to be fine for 2k.

Till today that is.
On a 55 mile trip the last 20 was jerky, last 2 miles TPMS, SCBS and TCS lights all flashed on and stayed on.
Parked up for the day and no lights for 5 miles then everything again along with Engine inspection light. And in limp mode.
 Couldnt pull in safely for 30 miles, stopped, turned off, all lights gone except Engine one, not in limp any more. 5 more miles and the rest came on, limp again.
Stopped at the nearest petrol station and checked tyre pressure, one was a little low. Reset TPMS, lights and limp gone except engine light.
Just taken the Sensor out and cleaned it a bit better again. I'll try to get it plugged in this evening as I have to do the same trip again tomorrow.

Any ideas?
Thinking just a coincidence with the TPMS

[Jamesbil]

So found a local guy still working this eve and he plugged it in to a Delphi system for me (€20 well spent)
Came up with codes 108 and 101, map and maf. Suggested possibly de coke intake and egr and dpf delete.

Also found codes
c0051
5031
UO41
 something about steering angle alignment?

[Jamesbil]

With the three codes, p0098, p0108, p0101 showing is it likely a faulty MAP sensor?

[twabrigs]

Anchorman - remind me how often you recommend the BG244 treatment. Looking back through my Amazon orders I see I did it in June 2018 which is probably 7000 miles or so ago.

[Anchorman]

Anchorman - remind me how often you recommend the BG244 treatment. Looking back through my Amazon orders I see I did it in June 2018 which is probably 7000 miles or so ago.

It depends what kind of running you do. On a healthy mix of hills, motorway and some city work, I do mine once a year but if I was doing short trips and often not getting warm I might do 2 or 3 doses. It gets a bit cheaper if you buy multiple packs.  You can’t overdo it even if you did one every couple of tank fulls but it isn’t cheap. It is cheap compared to the price of EGRs and DPFs and it’s not a Mazda thing it’s a modern diesel thing. 

[Jamesbil]

and now I'm getting "soot accumulation in dps too high" 

[twabrigs]

cheers for that Anchorman

[Anchorman]

and now I'm getting "soot accumulation in dps too high" 

I’m sorry but your problems are an accumulation of diesel, engine oil and emission system compounded all together.  I don’t know if you owned from new but it is vital that these engines get top quality oil and fuel.  What happens after that is to some extent down to duty level but any lapses in maintenance standards will eventually bite somebody’s arse and in this case it’s you.  If you are loooking for somebody to give you an answer I doubt you’ll get it.  You’ll have to do the things you can do.  My advice on BG244 has fallen on deaf ears but in any case I’m not sure your answer is £24 worth of additive.  If it were me, knowing the extent of expense you could be facing I’d give it a good try.  Add a can to a tank of premium diesel, let it run through for 10-20 miles, get it right up to temperature then go and drive it hard up the steepest hills you can.  If you are lucky, the heat and pressure will purge some of it out but if you are not, prepare to get serious with it.  It could start getting expensive.

[Jamesbil]

and now I'm getting "soot accumulation in dps too high" 

I’m sorry but your problems are an accumulation of diesel, engine oil and emission system compounded all together.  I don’t know if you owned from new but it is vital that these engines get top quality oil and fuel.  What happens after that is to some extent down to duty level but any lapses in maintenance standards will eventually bite somebody’s arse and in this case it’s you.  If you are loooking for somebody to give you an answer I doubt you’ll get it.  You’ll have to do the things you can do.  My advice on BG244 has fallen on deaf ears but in any case I’m not sure your answer is £24 worth of additive.  If it were me, knowing the extent of expense you could be facing I’d give it a good try.  Add a can to a tank of premium diesel, let it run through for 10-20 miles, get it right up to temperature then go and drive it hard up the steepest hills you can.  If you are lucky, the heat and pressure will purge some of it out but if you are not, prepare to get serious with it.  It could start getting expensive.

Thanks Anchorman 

I bought the car 2 months ago from V12 motors in Wolverhampton and exported it to Ireland. It came with a full Mazda service history all done on schedule. It has just gone to a local garage for a forced regen. After which he will diagnose and see if it needs a dpf clean.
I will also try the BG244, tho I have been using Dipetane.
The only diesel we get over here is diesel.. no premium, there are some Tesco stations but not many. I only buy from big brand stations.
I'll report back after the regen.

[Anchorman]

I’m immediately suspicious!  They could have sold it because it was playing up.  Alternatively, if you drive harder than someone who drove it like Miss Daisy, you might be dislodging more soot. The forced regen might work if they do the proper Mazda method.

[twabrigs]

Sounds a frustrating problem Jamesbil. Worth taking to a Mazda dealer for diagnostic?

Also must be some warranty from the Wolverhampton dealer? When you bought it presumably they knew you'd be exporting it to Ireland, did you agree anything re warranty procedure with them?