MOT test passed.

[Laird Scooby]

Originally Posted by tonyldee

Oil changed at last MoT using synthetic. Air filter approx. 1000 miles. Checked Government "transition period" for the 1993 and she still failed those marginal differences. Comment from testing station was basically "BLUE SMOKE IS AN INSTANT FAIL" Lambda sensor changed Dec. 2016

Heartbreaking but just how much do you keep throwing at the problem when the outcome is uncertain? Worn tyres, joints, blowing exhausts are all curable but when a motor runs sweet but the guy with the whip hand says NO, I feel that sadly it is time to let go. I would hate to think that she is to be crushed. I hope I can find a sympathetic breaker who can pas on so many good bits to fellow enthusiasts.

Add 0.5L synthetic ATF to the engine oil, run it a few days then do an oil/filter change using 10W40 SEMI-synthetic, not the el-cheapo carp from ECP (Triple QX - if that's what's in it, no wonder it's smoking!) but a reasonable quality oil.

Before adding your fresh 10W40 Semi-synthetic oil, add 1L of synthetic ATF then top up to the correct level with your fresh 10W40 oil. Also check the PCV system, i know it's different on the 3.0 but it can still cause problems. Also clean out the throttle body with carb & air intake cleaner including the AICV.

Check and if necessary, renew the air filter element, pull the fuse that provides the memory to the fuel ECU and refit after a few minutes.

Add some Cataclean to your fuel tank and take it for an Italian tune-up. Worth spending that small amount on it then going to the garage, asking the tester to put the gas analyser on manual and stick the hose up the tailpipes to see if it's cured - it should be.

What brand of synthetic engine oilo and what grade did you use last time?

[Ian21401]

Hoping that you manage to sort this. I would try what Dave has suggested. I’ve read elsewhere that these old engines don’t like fully synthetic oil, especially that stuff Dave has mentioned.
Just a thought, the lambda sensor is 3 years old. What brand is it, OE Bosch or an aftermarket? I’m not a fan of aftermarket lambda sensors.

[Laird Scooby]

Originally Posted by Ian21401

Hoping that you manage to sort this. I would try what Dave has suggested. I’ve read elsewhere that these old engines don’t like fully synthetic oil, especially that stuff Dave has mentioned.
Just a thought, the lambda sensor is 3 years old. What brand is it, OE Bosch or an aftermarket? I’m not a fan of aftermarket lambda sensors.

Very good points about the Lambda sensor Ian - something i should have thought of earlier in fact.

Whether it was a Bosch or aftermarket, was it a "direct fit" with the correct plug already on it or was it the type that arrives with butt-splic crimp connectors on it? If it's the latter, bin it and fit a new one - seriously! I've seen many mixture problems caused because of those butt-splices and more than one MoT failure as a result!

Another thing, this is a quote lifted from another forum i'm on but it's a similar thread, the car in question is a 98 Merc C240, not mine i hasten to add so i can't offer further information but you'll get the gist :

"My 1998 Merc C240 also passed Friday with no advisories. They said it was the first car with no advisories at all in the whole week and that well over 50% of cars they had tested had failed on one thing or another!

It just goes to confirm again that a well maintained older car does not need to be scrapped just because it might have been built to an older standard! "

Given my experience a few years back when Triple QX oil made 3 known good engines suddenly very smoky, if you've used that then follow what i suggested above - you'll be surprised at the improvements!

[tofufi]

Originally Posted by tonyldee

Heartbreaking but just how much do you keep throwing at the problem when the outcome is uncertain? Worn tyres, joints, blowing exhausts are all curable but when a motor runs sweet but the guy with the whip hand says NO, I feel that sadly it is time to let go. I would hate to think that she is to be crushed. I hope I can find a sympathetic breaker who can pas on so many good bits to fellow enthusiasts.

I would be surprised if it were anything too serious.

If you like the car so much, you could advertise it on here for repairs - someone may buy it and fix if it's in a condition worth saving

[loki_the_glt]

The Exxon Valdez will sail on for another year - a clean bill of health at the marine inspector's place, sorry MoT Testing station. And I didn't have to havethe hull scraped clean of barnacles!

[Laird Scooby]

Excellent news, congrats on the pass!

[dingov70]

Evening , I am an MOT tester & your car is subject to BET test , followed by a vehicle specific emissions test .

With the reading you have , you might be suffering from an air leak on the induction side of the engine AFTER the MAF , altering fuelling as a result .

The blue smoke would be an advisory only unless ( MOT manual 8.2.1.2.f or 8.2.1.2.g

https://www.gov.uk/guidance/mot-insp...rcial-vehicles these can be found in section 8 & the smoke would have to be very heavy to be a failure ! , read the wording carefully , we have to

[Laird Scooby]

Originally Posted by dingov70

Evening , I am an MOT tester & your car is subject to BET test , followed by a vehicle specific emissions test .

With the reading you have , you might be suffering from an air leak on the induction side of the engine AFTER the MAF , altering fuelling as a result .

The blue smoke would be an advisory only unless ( MOT manual 8.2.1.2.f or 8.2.1.2.g

https://www.gov.uk/guidance/mot-insp...rcial-vehicles these can be found in section 8 & the smoke would have to be very heavy to be a failure ! , read the wording carefully , we have to

That souds like it would be a very helpful post but who are you replying to?

[bob12]

Just what I was wondering but, I may have worked it out having ploughed through the pages of this thread!! Bob

[Laird Scooby]

Originally Posted by bob12

Just what I was wondering but, I may have worked it out having ploughed through the pages of this thread!! Bob

I have a tentative idea as well, if so the car in question has been up for sale on the forum for about a month now i think.