Some thoughts on the 2.2 C5 EGR SYSTEM (Long)

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KevMayer
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Re: Some thoughts on the 2.2 C5 EGR SYSTEM (Long)

Post by KevMayer » 13 Feb 2012, 23:17

Corsehf,

I'd be interested to hear what you did. For instance, you must have removed the injectors to get the inlet manifold off.

Have you refitted the manifold and especially the injectors. If so, how easy was it.

When will you/have you put it all back together? This sounds very interesting. I can't wait to hear how it performs when you get it back on the road. I strongly believe that cleaning out the inlet manifold and inlet valves will have a major positive effect on performance.

What size are the pics? If you use Photobucket you can resize them on the Photobucket website.

cachaciero
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Re: Some thoughts on the 2.2 C5 EGR SYSTEM (Long)

Post by cachaciero » 14 Feb 2012, 12:30

Hmm... well I have not done anymore on this except to put a filter screen in the EGR line to the inlet to hopefully limit the amount of carbon particles that find their way into the inlet tract. I too will be very interested in the result Corsehf get's. Although I have been considering wiring the swirl valves permanently shut as it is my belief that they bring little or nothing to the "performance" party. Wiring them shut would mean only a single inlet valve but that is all that VW 1.9 engine has and that produces a 140BHP. I do wonder if wiring the swirl valves shut and increasing the turbo pressure a little might not be the better performance option.

cachaciero

corsehf
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Re: Some thoughts on the 2.2 C5 EGR SYSTEM (Long)

Post by corsehf » 24 Mar 2012, 01:33

Sorry for the delay in replying but i have been checking the results - and they are Crap!!!
Yes the results should have been brilliant but they are'nt! - still must post the pics!
Reason i did the job was because the car went very thirsty going from 41mpg to 28 mpg average (on screen figures only).
In stripping down the engine, i noticed that the swirl valve actuator rod had snapped! - one answer i thought.
This is the second 2.2 i have stripped and i have yet to have an issue removing the injectors?
Anyway, cleared all the gunk away and rebuilt using new swirl valve and cleaned injectors and my mpg average is .............................................Still 28mpg!!! and it goes no better neither!!! - totally pissed off!!!
However, this last week, my car has started beeping at me with no message at first but now tell me that my engine temperature is too high?, a quick glance at the temp gauge and the needle is flying all over the place.
I would assume the temp gauge could have something to do with the poor consumption due to it running rich all the time??
What else could it be??

viorelovidiu
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Re: Some thoughts on the 2.2 C5 EGR SYSTEM (Long)

Post by viorelovidiu » 24 Mar 2012, 06:08

corsehf, have you trying to drive with the MAF sensor unplugged? your mpg average should get better. I got the same mpg average as you but with maf sensor off everything get better: acceleration, stable rev at idle, stable rev while trying to keep a constant speed, mpg average. Today I`m waiting for a new MAF sensor - original part VDO to see if the problem is cured. I`ve tried a Meat&Doria Maf sensor -a cheap one - but problem didn`t go away. the most annoying problem was: after engine got warm, at idle I could sense for 3-4 second an unpleasant vibration from engine and after that 3-4 seconds of normal idle and so on. it was like someone in the next car having a big subwoofer wooving me :lol: - with MAF sensor off doesn`t happen. With MAF on - I have strange reading in lexia: over 500 value as airflow when engine vibrating and 280 value when isn`t vibrating... I know that the correct value should fall every time within 200 and 290 value of measured airflow.
Also i have a strange problem with EGR System: when engine got warm egr is activated and it`s reving down my engine running very rough. this happens sometimes even when idleing :evil: EGR sistem was completly cleaned up and i have bought a new electrovanne to check all of them but no problems found. somehow the computer is activating EGR when it shouldn`t and keeping it open...

Sorry for my english

Any help would be appreciated
Ovidiu

corsehf
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Re: Some thoughts on the 2.2 C5 EGR SYSTEM (Long)

Post by corsehf » 25 Mar 2012, 01:18

Not sure about just unplugging the MAF sensor? - surely that would put the car into LHM?
I do have a spare from my old car i could use - not sure how good it is but i could try it.
Will need to get hold of a Temp Sensor soon and change it - anyone know its location??

KevMayer
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Re: Some thoughts on the 2.2 C5 EGR SYSTEM (Long)

Post by KevMayer » 25 Mar 2012, 19:28

Temp sensor is on the right hand end of the cylinder head (looking at front of car), somewhere below the EGR pipe. Green I think. One of the chaps on here recently had a problem with his sensor and explained where it's fitted.

viorelovidiu
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Re: Some thoughts on the 2.2 C5 EGR SYSTEM (Long)

Post by viorelovidiu » 28 Mar 2012, 17:37

my problem is solved! it was simple as hell! someone mixed up vacuum pipes between EGR electrovanne and one of inlet air flaps.... I rearranged them by following the colour of the plugs with the colour dotted on vacuum pipes.

One note: On phase 1 colour is painted outside the plug while at phase 2 is inside and you`ll have to remove them to check colour :)

landyman
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Re: Some thoughts on the 2.2 C5 EGR SYSTEM (Long)

Post by landyman » 05 Oct 2015, 09:24

on a related topic, I've a 2.2 Hdi C5 with around 140k on the clock which I've recently been having problems with.

It started firing on 3 and anything below 1500 RPM, this turned out to be a faulty seal on the injector which I replaced and that no longer leaks (good tip to get them out, get the engine REALLY hot then do it quick, melts the tar which will have accumulated and was easy once the engine was hot)
Then the car was really sluggish - almost undrivable. replaced the MAF sensor, now goes like a good un
Then the FAP blocked, tried the usual jetwash technique but to no avail, got min diesel additive warning and since there is no sensor in the additive tank I guess it had actually already run out and blocked the FAP so I put a litre of fluid in and replaced the FAP. Partial success the FAP blocked again but would clear if I drove carefully. I gather the 'diesel additive minimum level' error will persist but it will add additive anyway if it's there?

I have noticed there is quite a bit of smoke on hard accel which goes if I put the original MAF back - i.e. not engine wear or turbo oil seal related. The conclusion I came to is that it's overfueling causing the smoke and I reckon the EGR is stuck (open?) so I blanked it.

Finally the point of the post, the car seems to be running a lot better with a lot less smoke at hard accel and no problems reported by the comp except the fuel additive error. Will I pass the MOT or will it fail be cause I have blocked the EGR?

Al
.

cachaciero
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Re: Some thoughts on the 2.2 C5 EGR SYSTEM (Long)

Post by cachaciero » 05 Oct 2015, 23:37

As the current test only tests for smoke and co2 they will have no way of knowing that the EGR is blanked, however a check for NOX would / should show elevated levels of NOX components with a blanked or non functioning EGR valve. The fuel additive error will I believe.result in a fail, you need a Lexia to reset the counters in the additive controller.

You don't say if this is a MK1 or later, if Mk1 there is actually an additive level sensor which seems to often fail or otherwise not allow resetting of the additive ecu. On later cars the ECU calculates the level in the tank and stores the values internally these need to be reset when an new FAP and or additive is added otherwise it will still believe that the additive is low.

landyman
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Re: Some thoughts on the 2.2 C5 EGR SYSTEM (Long)

Post by landyman » 09 Oct 2015, 09:49

after running it for a few days with the EGR blanked it has to be said it's much better without the EGR.
The performance as far as I can tell is unchanged however I get much less smoke on hard acceleration and 47 MPG instead of 41.
Reading up a bit on it it seems the EGR/FAP/complex turbo and swirl are like giving a patient one drug for something then another drug to counter the side effects of the 1st and then another to counter the side effects of the 2nd - end result is only slightly better than you started with but with 3 drugs instead of none. I'm sure it worked better on a rolling road when the car was brand new. May put me off buying another diesel tbh.

cachaciero
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Re: Some thoughts on the 2.2 C5 EGR SYSTEM (Long)

Post by cachaciero » 09 Oct 2015, 22:07

Interesting observation now first question why would you see any smoke with a FAP? if one takes the position that smoke is actually carbon particulate ie visible soot which should be caught in the filter then the only things left would be NOX components,Co2 and water vapour, in a hot engine I would'nt have thought that these would be particularly visible.

However assuming that there is some visible smoke due to leakage in the FAP or something the fact that it smokes more with the EGR in circuit would imply that too much exhaust gas is being inducted resulting in inadequate oxygen for efficient combustion hence more smoke which would tend to be confirmed by the poorer fuel consumption.
However another take on it could be that injecting inert gas into the combustion chamber causes the combustion process to produce soot with much smaller particle size so more chances of getting through a filter and being more visible :-) you takes your pick so to speak.
I would consider the possibility that the EGR valve is sticking after all most engines spend a lot of time at the idle end of the range when the EGR will be max open so I would imagine the chances of it coking up in the open position are quite high. Your take on one drug to cure another is very close to the truth. EGR was introduced to reduce the Nitrous Oxide emissions which if set up correctly it does with little negative impact. However it was then discovered that the resulting fine soot particulate produced using EGR was even more injurious to human health than the original soot, enter the FAP. .
I too am considering going back to petrol, have done so in part. I still run a 2.2 estate which is long in the tooth, for load lugging and a Prius for all the rest, and having had the two back to back as it were for a couple of years which is the better car is a close call, The Citroen has the ride and comfort also better quality materials in the cabin and generally it feels a solid well built car but it does need regular fettling to keep it going. The Prius has far superior electronics the Hybrid system is magic and all you need to do is put petrol and oil in it but the interior trim has not worn well and the ride...? well lets not go there though a new set of shocks may improve things somewhat. I need to downsize the fleet and at the moment a Lexus RX400H seems to tick many of the boxes, just need to find one that is not old, without telephone number mileage at a price I can afford :-)