Failed MOT on emissions

[classicswede]

Conwy is not at all far from me.

[Ian21401]

MAF was replaced Oct.2014 (186181 miles) OE VO8251497, Bosch 02802 12016. Never contemplated cleaning it. ( Was once advised to try cleaning a lambda sensor with brake cleaner. Did so and wrecked it.)
I take your point about the ECU and cleaning the PCV again a short while later.
Oil: Last 4 years used Castrol Magnatec, part synthetic, 10W 40, A3/B4 as Costco cash & carry have it on offer occasionally and I stock up. Previously used Vauxhall’s part synthetic 10W 40, A3/B4 as brother able to obtain it discounted at local Vauxhall dealer until they were taken over by Tustain.

[Laird Scooby]

Cleaning a MAF needs to be done with either carb cleaner or for preference, MAF cleaner. Best way to clean a Lambda is an Italian Decoke.

As for the oil, nothing untoward there, not my own choice but nothing wrong with them. The reason i asked is for many years i used ECPs own brand (Triple QX) 10W40 semi-synth in my cars. Changed the oil in three cars (827 Coupe, 827 Sterling and the then recently acquired 760) and all three engines became smoky instantly including smelling like they were burning oil from the exhaust.

I'd never had a problem with that oil before but found something online that suggested it was recently changed to include recycled oil.

Did an oil/filter change on the Coupe and substituted a litre of ATF-U for some of the new oil to help clean things through and the smoking stopped on it. When it got towards the time it needed another oil/filter change, there was a faint whiff again but nothing like it had before.

Likewise on the Sterling and 760 - i won't have another problem with the Triple QX oil as i won't use it now, not even in my lawnmower! I tried it and even that started smoking and was a pig to start! Changed it for some of what i had left over from substituting a litre of ATF-U in the cars and normal service was restored to the mower as well!

This is what i use now :

https://www.eurocarparts.com/ecp/p/c...4211&0&cc5_245

With their discounts it usually comes out about £13 and does have a slight pong like Castrol but nowhere near as strong. Seems to stay in grade better between changes than the original Triple QX as well and stays fairly clean between changes too - always a bonus!

[AllHailKingVolvo]

Originally Posted by Laird Scooby

Cleaning a MAF needs to be done with either carb cleaner or for preference, MAF cleaner. Best way to clean a Lambda is an Italian Decoke.

As for the oil, nothing untoward there, not my own choice but nothing wrong with them. The reason i asked is for many years i used ECPs own brand (Triple QX) 10W40 semi-synth in my cars. Changed the oil in three cars (827 Coupe, 827 Sterling and the then recently acquired 760) and all three engines became smoky instantly including smelling like they were burning oil from the exhaust.

I'd never had a problem with that oil before but found something online that suggested it was recently changed to include recycled oil.

Did an oil/filter change on the Coupe and substituted a litre of ATF-U for some of the new oil to help clean things through and the smoking stopped on it. When it got towards the time it needed another oil/filter change, there was a faint whiff again but nothing like it had before.

Likewise on the Sterling and 760 - i won't have another problem with the Triple QX oil as i won't use it now, not even in my lawnmower! I tried it and even that started smoking and was a pig to start! Changed it for some of what i had left over from substituting a litre of ATF-U in the cars and normal service was restored to the mower as well!

This is what i use now :

https://www.eurocarparts.com/ecp/p/c...4211&0&cc5_245

With their discounts it usually comes out about £13 and does have a slight pong like Castrol but nowhere near as strong. Seems to stay in grade better between changes than the original Triple QX as well and stays fairly clean between changes too - always a bonus!

The Gulf is what I've got in my 744 and 245 at the moment, Dave...second your comments about it being a good oil, it's stayed nice and clean for 3000 miles in the 245 since the last change and 2000ish in the 744, both cars feel smoother on it too.

[Laird Scooby]

Originally Posted by AllHailKingVolvo

The Gulf is what I've got in my 744 and 245 at the moment, Dave...second your comments about it being a good oil, it's stayed nice and clean for 3000 miles in the 245 since the last change and 2000ish in the 744, both cars feel smoother on it too.

It's not just me then that thinks mine run smoother on it Phil! I thought it was that i had a good oil in the engine again after the dodgy stuff so didn't pay it much attention.

[Dirty Rooster]

Originally Posted by Laird Scooby

I've done a bit of digging

Mine's a 1993 2.0 Turbo,
so when I eventually really really fail an emissions test
I can "get out of jail free"?

[Ian21401]

In my 940, before the Vauxhall oil I used Comma semi synthetic from a particular trade only motor factor at trade price. I’d used that in my daughter’s Orion and both my Marinas and before them a Mk3 Cortina. Before that I had a couple of Triumph Heralds for quite some time and used only Duckhams Q 20/50 in them. I did try some Castrol GTX in once which I had won in a motor club quiz. The rocker cover filled with mayonnaise. I changed that back to Duckhams sharpish. I’ve never used any of the others you’ve mentioned.

[Laird Scooby]

Originally Posted by Dirty Rooster

Mine's a 1993 2.0 Turbo,
so when I eventually really really fail an emissions test
I can "get out of jail free"?

Looking at the list etc, i'd say you standa a good chance!

Originally Posted by Ian21401

In my 940, before the Vauxhall oil I used Comma semi synthetic from a particular trade only motor factor at trade price. I’d used that in my daughter’s Orion and both my Marinas and before them a Mk3 Cortina. Before that I had a couple of Triumph Heralds for quite some time and used only Duckhams Q 20/50 in them. I did try some Castrol GTX in once which I had won in a motor club quiz. The rocker cover filled with mayonnaise. I changed that back to Duckhams sharpish. I’ve never used any of the others you’ve mentioned.

Comma do some good products but the thing to remember with them, particularly with engine oil, is they are a blender and not a refiner.

In other words, they will buy say 1000L of base oil 10W40 mineral oil and 1000L of 10W40 synthetic, mix the two together to create semi-synthetic adding the additives to reduice friction, improve viscosity over time and so on and have about 2000L of semi-synthetic 10W40 oil.

Part-synthetic oil (in case anybody is wondering) is different in that it can be mineral oil with synthetic additives and won't necessarily give the prolonged protection that semi-synthetic will.

Gulf on the other hand are a refiner so everything is done in house, rather than buying in bulked oil so there is less risk of contamination (like i suspect happened with the Triple QX stuff i had that was dodgy - ECP get it blended for them) and a generally more consistent standard. It's worth trying a 5L bottle of it next time you do an oil/filter change, i've recommended it across 3 forums i'm on and had good reports back on all three.

[besidetheseaside]

In a moment of boredom I looked at the inside of the throttle body and it was nice and clean so I left it alone. Took off the oil separator tank and it was clean as a whistle.

[besidetheseaside]

Also been discussing my problem with like minded friends and the misfire keeps worrying me, it was very rhythmic, almost pulsating from the exhaust, not random like you would expect from a random misfire.