c5 2.2hdi inlet throttle butterfly question

[antonioneves]

I have recently remaped, blocked the EGR closed electronically and physically and electronically removed the DPF.

its a different beast alright. from 1500rpms it pulls strongly. nothing exagerated, but stock was killing me with little power till 2000rpms roughly. the vacuum line of the swirl was broken in the connector and the anti pollution fault never came back, so a week later, I did the remap/dpf removal.
Happy with it but stock, the car would pull easy up to 190kmh on a flat road, but that was it. I assumed a 2.2 with 136 ponies could do better, but the dpf was still there and i thought it could have been that.
after a remap, the car pulls very strongly up to 190, but thats it. eventually it will continue to go, but i could never reach anything above 200 and that is after a lot of flat road... so I started to investigate a bit more and read some interesting things here, and am looking for confirmation/expertise/opinion:

accelerator cable is apparently ok, no slack, cant move the peddle upwards, cable seems tight.

I took out both inlet pipes while idling the engine (warm) and the lower one (heated air) is stuck close at idle while the upper one (intercooled) is closed, but flapping intermittently like it can never close completely, and a little gap allows air in. its like opening and closing less than an cm on/off continuously (my apologies for the bad use of English). I can feel a little vibration also inside the car at idle, which i am blaming on that inlet valve flapping.

I took out both vacuum lines that go into both inlet butterflies, and let them open. I took out the car for another long stretch of road, but again, after 190kmh there's little more to it. and I noticed a bigger lag in turbo kicking in and the MPG dropped, but I am assuming it is normal as there is more room to fill with air since both inlets are wide open. and the engine vibration at idle is not there anymore.
but I do ear a funny noise inside the car if I am really quiet and listening while strolling in 1st gear, no throttle. I cant really express it in English, its like a funny humming noise...

My questions:
the lower inlet with hot air, should be only open with the engine cold or always at idle, regardless of being cold or warmed up?
the upper inlet, intercooled, does normally open wide while the lower one is closed under full throttle?
is the flapping of the intercooled butterfly inlet normal? I mean it doesn't sound like it is. if both butterflies are closed at idle how does the engine get air?

and my apologies for such a long question(s) in a opening post, but its hard to find a mechanic that doesn't call me paranoid. ( as you can probably imagine after reading this )
car drives fine, MPG is ok, I was just expecting more of the 2.2 in the upper range.
don't get me wrong, if I wanted speed, I wouldn't have bought this car, and I rarely get a chance to drive above 130, and 99% of the time I don't need that much power, still... I just think its weird it doesn't go a bit faster and doesnt have more punch in the upper range, that's all. having said that, it does 4000 rpms around 190 so, I guess a diesel shoudnt produce that much power after 4000...
And that flapping of the inlet butterfly and vibration at idle definitely doesn't feel normal to me... but i can be wrong. so please feel free to tell me to shut up, reconnect those vacuum pipes as everything is working as it should and go enjoy my car.

TIA.

[antonioneves]

anyone?

about to go and buy the EV that controls the butterfly to rule it out as it is cheaper than the whole inlet one...

[SaabC5]

4000rpm at 190kph equates to 118mph, Citroen list the top speed of the 2.2HDi manual as 127mph so you are only 9mph off top speed, understandable on an older car that will have lost a bit of zip even if it has been remapped. Don't forget the gearing will have an effect on top speed, it may get there quicker but it won't go any faster than the gearing allows.

[antonioneves]

thanks, understand that. many factors at play there.

and about the inlet butterfly symptoms? thats whats really worrying me.

[waynedance]

http://www.citroenet.org.uk/passenger-c ... tech6.html" onclick="window.open(this.href);return false;

Possible not going to answer your question but some good information.

[antonioneves]

thx Wayne, but doesnt cover the inlet dual operation "normal behaviour".

does yours do the same?

[waynedance]

No idea what mine does, would need to look at.

[Monkeyfeet]

The valves should not flap about, there's normally a spring action, (in the case of the intercooler valve) to keep it open.) Changing the e/v won't change this. I've removed the vacuum circuit e/v's completely. Also have been thinking about removing the intercooler valve internals completely, but don't think it will get much gain so haven't bothered yet.
I'd also like to know if the valves are supposed to do anything other than bypass the intercooler to heat up the engine for FAP/DPF regeneration. Maybe used when engine is cold to supply warmer air but I've not noticed any difference in cold engine running whatsoever since removing them.

By the way, the way you express yourself in english is very good, your grammar and spelling is way better than a lot of native english speakers!

[antonioneves]

thanks Monkeyfeet, I have also removed the vacuum for a while in the intercooled valve and the hot one, but leaving them always open resulted in extra turbo lag and higher fuel consumption...
did you noticed the same on yours?

So to sum it up: it seems I need a new inlet IC valve, or consider leaving it open at the expense of the lower MPG?
the flapping about still intrigues me. with no vacuum, the valve stays fully open. so the Spring must be good, otherwise it wouldnt fully open or close, am I right?
the flapping cant be a leak in vacuum, because I cant find it and a leak would most likely result in always open, and not in flapping.
hence why I thought the thing that controls the valve, i.e. the EV, would be the thing not working properly causing the flapping...



from what I read/tested thats the only thing they do, bypass for warm up and dpf regen.
and I also didnt notice anything in cold engine running. except for higher mpg.

when you say you removed the vacuum circuit and EVs completely, you're reffering only to the 2 Evs controlling the hot and cold valves, right?

[Monkeyfeet]

Well I can't say that 'I've noticed more lag. Also not sure why bypassing the intercooler would give less mpg, I'm sure that the power drop would be noticeable though. See what you mean now, re the valve flapping when connected, that sounds like strange behaviour. If you think that the intercooler e/v maybe suspect you could try swapping it for the other e/v and see what happens.
Also I see that you've electronically disabled the egr - well I did that too but noticed the biggest change when I fitted an egr blanking plate (£4, ebay) so in my case the egr was probably stuck open a bit. Not sure if that would effect high speed running but its a simple thing to eliminate from the equation.
And yes re the e/v's I've ditched the intake, by-pass and egr e/v's. That has cured the overboost alarms that I was getting (maybe a vacuum leak that I never could find)

[antonioneves]

ok will try to swap EVs and see how it goes.

[antonioneves]

Well, I decided to take out the vacuum for both inlets and the egr and also blanked it. less tubes in the engine bay. no leak on any of them, and now the inlet hot side is permanently closed and the IC'd is always open. I'll live with it.
no noticeable change in performance.

[antonioneves]

I think I got why the car doesnt go faster/better.

hooked up car to laptop and notice the turbo spools up to 1.0 / 1.2 bar and thats it.
which means since the remap is asking for 1.5 stable and 2.0 bar peak, its not being able to deliver what's asked.

I dont have vacuum leak in the hose that goes into the wastegate. no errors, so... new turbo?
is there a way to adjust the wastegate like in a non vgt turbo with external wastegate which has a thread?

[cachaciero]

The Turbo is a variable geometry device in that the amount of exhaust gas passing through the turbine is modulated by a sliding difuser driven by a vacuum driven servo, now if this sleeve was to seize then it could well be that the turbo will never deliver maximum boost. I am told that this is not an uncommon scenario on VAG diesels.
It would seem to me from such drawings I have that carbon build up could also limit the amount of movement even if not seized
This brings me to another thought, the Eolys injection results in a softer carbon which burns off at lower temperatures than in a non eolys injected system, this carbon passes through the turbo, I do wonder if cars that have had the DPF removed and as a result are creating harder carbon deposits which do not burn may be more susceptible to seizing or carbon build up on the variable geometry diffuser.

cachaciero

[KP]

To be honest the only way to find out is to get the turbo off and take the compressor housing off (mark it at a few points so you can fit it back as it was!) and the turbine housing and see what's happening. You may find something like nitromors could clean it off for you and have it good again.

Ideally citroen should have set the car up so that the air went thru the charge cooler/heater then the intercooler to get the best reduction in air temperature before going into the inlet manifold.

If you have stopped off the charge cooler/heater by disconnecting it I would look at taking it out of the pipe work entirely.

A small piece of copper tube would complete the water circuit, an appropriate aized rubber cap for the inlet manifold inlet for it and then maybe the same or a replacemt section for the rubber bottom hose to take out the t piece.