OM642 350 CDI intake valve motor bypass or replace

myromeo

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Following on from my previous thread it’s been diagnosed that my intake valve shutoff motor (swirl flap motor??) has failed. I’ve read a few threads suggesting a popular mod is to disable this via a simple resistor.

Question is, my car is GAD remapped and has the EGR Valve disabled in software. Cost aside, would I be better performance wise replacing the motor or disabling it via the simple resistor mod?

Car is 2012 CLS350 CDI 265hp and has around 75k miles.
 

M80

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It's more to do with emissions,
so if you bypass like the EGR the Gov't will want to put your balls through a mangle, twice.

Install the resistor, you could always take it out again if you don't enjoy the mangle the 1st time.
 
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malcolm E53 AMG

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At that mileage and age of car I would replace it and check that the oil cooler isn’t leaking at the same time as you are half way to doing that job in the process
 

Craiglxviii

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EGR valve disabling is illegal as it takes the car away from its homologated condition. Arguably it makes it uninsured unless you’ve declared that modification..?

Secondly, employ the swirl flap motor resistor shunt as that’s demonstrably not an MOT failure.

That might sound like a contradiction, it isn’t. EGR technology was introduced in Eur5 and is enshrined in emissions standards. Dynamic Swirl Flaps contribute about 5% to the extreme edges of the emissions performance envelope and make the design engineers’ jobs easier to do, and are not enshrined in emissions standards.
 

malcolm E53 AMG

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I would also look into why the swirl flap motor failed it’s usually due to oil seepage from the turbo
 

Wighty

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I would put the resistor mod in for £1.00 and give it some thought later . My car had it put in a couple of years ago just as a precaution , haven’t noticed any difference .
4.7kohm resistor in middle 2 terminals of the wire that goes to the ilps motor , 30 minute job
 
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myromeo

myromeo

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So ethics aside (I really don’t mean to turn this in to a EGR delete conversation, that has been done to death a thousand times!) Just bypass it? I’ll get it looked at properly when I can get it booked in for a service as it’s due shortly anyway
 

Craiglxviii

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It’s not ethics, its legislation. Far more punitive!
 

Craiglxviii

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Who's honesty going to get caught after electronically disabling their EGR valve?
Anyone whose MoT tester decides to poke a bit?
Anyone who has an investigation following a collision?

Ask VAG this question...
 

matthew k

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Anyone whose MoT tester decides to poke a bit?
Anyone who has an investigation following a collision?

Ask VAG this question...
An MOT tester isn't even allowed to remove the engine top cover let alone dig around in the wiring loom. I also think it's highly unlikely to be taken into consideration during a collision investigation, it doesn't release more power. The VAG emission scandal involved a huge multinational company deliberately cheating emssion regulations, it's irrelevant to this discussion.
 

Wighty

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Do it once
Do it right
Do it properly
That’s my moto , but it depends on other factors .
Cost/budget
How long you intend to keep it , are you going to be trading it in soon (and given a derisory low price regardless of how good condition your pride and joy is )
 

LostKiwi

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An MOT tester isn't even allowed to remove the engine top cover let alone dig around in the wiring loom. I also think it's highly unlikely to be taken into consideration during a collision investigation, it doesn't release more power. The VAG emission scandal involved a huge multinational company deliberately cheating emssion regulations, it's irrelevant to this discussion.
None of which alters the morality or legality of knowingly making your vehicle pollute more in order to save on maintenance costs.
 

matthew k

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None of which alters the morality or legality of knowingly making your vehicle pollute more in order to save on maintenance costs.
I guess, although it's possible that there's little actual benefit to reintroducing exhaust to the intake, if you take the carbon build up into account. I suppose by reducing combustion temps it lowers NOX production?
 

M80

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None of which alters the morality or legality of knowingly making your vehicle pollute more in order to save on maintenance costs.

I would suggest that that's a sticky argument.

Should I buy a newer vehicle because it has a DPF and adblue?
Should V8 petrol drivers replace theirs with smaller engined cars that use less fuel and so pollute less?
Should those w/o cars be given a financial bonus by the Gov't?
Should we develop the canal infrastructure so that more freight might be moved that way?
Should taxi drivers lose their taxi licence for leaving their engines running while waiting for a fare?

I am in favour of scrapping hot hatches that pollute our ears with loud horrible sound, and that 'also' includes gutted exhaust sound.
 
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myromeo

myromeo

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Wish I’d never mentioned EGR as it’s not what I asked about. Can we get back on topic please?

the inlet shut off valve motor / swirl valve motor That is commonly removed on these engines... now that it’s failed is there a performance benefit to the bypass mod or does the engine perform better with it working. I believe it’s to do with improving air fuel mix at low engine speed to improve efficiency, nothing to do with emissions and certainly nothing illegal of modifying it.

With it unplugged there is definitely a loss to low down response but this could be due to the engine light being on.

please don’t turn this in to a discussion that it’s not.
 

Wighty

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Wish I’d never mentioned EGR as it’s not what I asked about. Can we get back on topic please?

the inlet shut off valve motor / swirl valve motor That is commonly removed on these engines... now that it’s failed is there a performance benefit to the bypass mod or does the engine perform better with it working. I believe it’s to do with improving air fuel mix at low engine speed to improve efficiency, nothing to do with emissions and certainly nothing illegal of modifying it.

With it unplugged there is definitely a loss to low down response but this could be due to the engine light being on.

please don’t turn this in to a discussion that it’s not.
I have noticed little difference with my bypass mod , if I was pushed I would say that there is slightly more engine braking when coming off the accelerator . Bu that’s it
Yes your car is still in limp mode
 


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