EGR mod question

weemac · Oct 25, 2019

DevonGuy said:
It's a matter of choice but for information my Td4 has just passed its MOT for the 3rd year running with a bypass fitted. It's a "stealth" version but there are so many F1 Td4s in North Devon that it's impossible that the tester doesn't know what an EGR bypass looks like. He also commented that the emissions are "silly clean". My assumption is that either the bypass is considered passable or that testers have personal leeway.

So, just done some reading, instead of contributing more nonsense to the forum

. It seems that a blanked or entirely missing EGR system will not cause you to fail an MOT. You will fail if the emissions fall below the threshold as a result of the inop EGR. However, a missing or obviously modified DPF will fail your MOT. I thinks that where I was getting mixed up.

Out of interest, have you made any intentional changes to your TD4 that give you "silly clean" emissions?

weemac · Oct 25, 2019

Treecol77 said:
Oops! Didn't realise that one. Should be interesting to see what happens when it's all back together with said sensor soaked in Mr Muscle.
Thanks for the tip on the decoke kit.

lol

To be fair, if the manifold is really caked up, the 7 or 8mm hole that feeds into the sensor will be full of crap anyway. Therefore it's not giving a true pressure reading. I think it gets substituted at that stage to keep the engine happy. Do not be tempted to stick anything in the hole on the end of the sensor. Do your best to blast it out with compressed air and/or brake clean. Then dry thoroughly.

Expect a bit of whiteish smoke when you get it all back together and start/run for the first time.

DevonGuy · Oct 25, 2019

weemac said:
So, just done some reading, instead of contributing more nonsense to the forum . It seems that a blanked or entirely missing EGR system will not cause you to fail an MOT. You will fail if the emissions fall below the threshold as a result of the inop EGR. However, a missing or obviously modified DPF will fail your MOT. I thinks that where I was getting mixed up.

Out of interest, have you made any intentional changes to your TD4 that give you "silly clean" emissions?

The only alterations I've made are silicone turbo hoses, EGR bypass and the BMW-style cyclone oil separator on the crankcase vent. I do keep it thoroughly serviced at the correct intervals though.

Nodge68 · Oct 25, 2019

weemac said:
Out of interest, have you made any intentional changes to your TD4 that give you "silly clean" emissions?

A correctly running TD4 will run clean. However if the MAF single is low (old MAFs have a low signal), then the exhaust will be silly clean.

Mine is so clean, the MOT tester doesn't even bother printing the readings, as the readings are zero.

Moron · Oct 25, 2019

weemac said:
So, just done some reading, instead of contributing more nonsense to the forum . It seems that a blanked or entirely missing EGR system will not cause you to fail an MOT. You will fail if the emissions fall below the threshold as a result of the inop EGR. However, a missing or obviously modified DPF will fail your MOT. I thinks that where I was getting mixed up.

Out of interest, have you made any intentional changes to your TD4 that give you "silly clean" emissions?

Read the MOT testers manual.......its online any emission control equipment fitted by the manufacturer obviously missing, modified or defective is a major fail , that includes the egr valve

weemac · Oct 25, 2019

Moron said:
any emission control equipment fitted by the manufacturer obviously missing, modified or defective is a major fail , that includes the egr valve

Hmm... So I was right the first time

Looking more and more like a gutted EGR is the way to go.

Treecol77 · Oct 25, 2019

So having road tested it, all seems good except the original issue I was having is still there slightly. The fault code for the boost sensor showed up and I cleaned it then forgot to order a new one. So now, whilst my engine sounds much quieter after new injectors, very smooth with the new hoses, whilst going downhill at steady revs (most noticeable over 50mph) there is now a very very slight flutter -like a petrol car with the points not set correctly. So I'll order the sensor, do you think that will cause that flutter?

Nodge68 · Oct 25, 2019

Treecol77 said:
So now, whilst my engine sounds much quieter after new injectors, very smooth with the new hoses, whilst going downhill at steady revs (most noticeable over 50mph) there is now a very very slight flutter -like a petrol car with the points not set correctly.

That's the 2K misfire, which happens on light or trailing throttle. There's no definite cure, but an EGR bypass can make it worse on some engines, and no difference on others.

Treecol77 · Oct 26, 2019

Nodge68 said:
That's the 2K misfire.

Ok, not heard of that. It is much better than it was before I got the car and barely noticeable now, so the EGR mod certainly hasn't made it worse.
Thanks for letting me know as that saves me trying to work through loads of other things it could be.

Nodge68 · Oct 26, 2019

Treecol77 said:
Ok, not heard of that

Search TD4 2K misfire, as it's been talked about for about a decade.

Treecol77 · Oct 26, 2019

*sigh*
Did a search. Depressed now as my rear n/s window went grind clunk and now wont work. Seriously thinking of getting rid of it now. Are the 2.2 FL 2 any better?

Nodge68 · Oct 26, 2019

Treecol77 said:
Did a search.

And what did you find out?

Treecol77 said:
Depressed now as my rear n/s window went grind clunk and now wont work. Seriously thinking of getting rid of it now.

It's just a cable. They break for a pastime. Grease the cables when you fit the replacements, and it'll last years.

Treecol77 said:
Are the 2.2 FL 2 any better?

Better is a tricky question. More difficult and more expensive when they need fixing. They're an the next price band up for maintenance and parts costs. Not as expensive as a Discovery 3 or Range Rover Sport, but more expensive than the FL1.

The FL2 is a much more modern vehicle, so is more modern to drive. More refined, more powerful, just as economical, better road manners and better equipped (except the lower spec models). However all the better ness comes with an increase in running costs.

Treecol77 · Oct 26, 2019

Nodge68 said:
And what did you find out?

,m

That plenty of TD4's suffer fro this 2k missfire and a good number of people with far more knowledge than me aren't able to find out exactly what it is. I saw you were talking about possible oil contamination. So I will replace the boost pressure sensor as that was throwing a fault and see if that helps. If not, I will try to ignore it, then I don't have to consider a FL2 that will be more costly to keep on the road!

Nodge68 · Oct 26, 2019

Treecol77 said:
I saw you were talking about possible oil contamination. So I will replace the boost pressure sensor as that was throwing a fault and see if that helps. If not, I will try to ignore it

Yes. I have a hunch that the crankcase breaker allows oil to contaminate the intake. This oil then randomly burns off, causing the misfire.

Or under very light throttle, the amount of oily air that's bypassing the MAF is upsetting the injection volume, giving the misfire.

I ignore it, and have done since I figured I wasn't going to find the true cause .

EGR mod question

weemac

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weemac

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DevonGuy

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Nodge68

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Moron

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weemac

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Treecol77

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Nodge68

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Treecol77

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Nodge68

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Treecol77

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