Technical EGR valve, throttle body or inlet manifold problem?

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Hi, I have a serious loss of performance after a EGR swap, throttle body clean and inlet manifold clean. I have changed MAP sensor for a spare one I have and also tried disconning the MAF air flow meter, no difference. My main worry is if the garage have dropped some of the carbon tar inside the inlet manifold. The car has about 20% power and shows the codes in the photo, even though the MAF has not been touched. The garage wont mess with it anymore, it when in with a EML on due to the low flow of air going in via the EGR valve. What can I check next ? I cant see how the MAF can get dirty from cleaning the Manifold ?
 

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s130

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I wonder how they cleaned the inlet manifold without removing it which is a complex job. To my knowledge you just can't stuff a bottle brush in there because if nothing else there are the swirl valves to consider.

You say EGR swop. I assume you mean a replacement EGR valve?

Those fault codes all seem to relate to the manifold and throttle body. This would suggest a major/multiple wiring and/or connector issue.

You need to inspect and if necessary use the Fiat Croma eLearn Manual on this website to trace the continuity to the ECU pins.
 
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thx, EGR was swapped as I have 3 of them for the car. I cleaned and checked the one that when on. They cleaned the manifold with a can of spray cleaner and scraped out what they could from the opening. I am highly concerned some will have fallen inside the manifold and gone through the engine combustion chambers. Today I have had the air filter out and cleaned the MAF sensor, unplugging the MAF made no difference the other day. The fault codes only appeared after driving at 4000rpm. I think the throttle body could be the problem, as thats been cleaned, but I'm guess taking an educated guess.

The mechanic gave me this pic, I guess its where the throttle body fits onto the manifold ?
 

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jackwhoo

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Try reading the live data from the map sensor , different engine rpms , if you dont see any turbo boost then you may have a boost leak (stuck open egr valve?)
Or turbo control vacuum tube problem.
 

s130

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That intake full of crud shows exactly why diesels are dirty cars.

On a normally aspirated diesel the intake would be far cleaner even with EGR. The problem with turbo diesels is that even a good turbo leaks oil into the intake air stream which is then mixed with the EGR soot and then settles on the cold intake surfaces.

How any government could back diesel for car usage where dynamic operation is required is a mystery. Politicians not properly researching, then being fed duff data based on out of factory data with no higher mileage/age data, etc. And if that was not enough the cheat devices cleaned up the act.
 
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I agree about our government backing the wrong fuel. LPG should have been chosen, just like in Italy. That's what my old V8 Jeep runs on @ 57.9p per litre in Devon on holiday last month. Road tax for petrol converted = alternative fuel cars got just a £10 reduction, they are fools when LPG is such a clean alternative.

EGR is working as I have seen it opening on Multiscan when engine is revved.

I tried banking off my inlet manifold where the EGR joins it on my Croma 2.4 JTD, it just puts EML on so as soon as I purchased it I fitted a 4 holed blanking plate. I can only assume it was too late, or the plate still lets too much carbon through into the manifold.

Question - what can I spray into the inlet manifold via the EGR opening and the MAP opening to disolve the carbon, what about petrol and leaving it a day or 2 ? Its a massive job to change inlet Manifold
 
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g8rpi

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The fault codes you are seeing in MES indicate a electrical issue rather than a blockage. Need to check all the connecrtors and loom in thea area. Possibly a swapped connector, loose connector, damaed pin or damaged loom.
What engine? a 24V?
What where the garage contracted to do? If it was to swap the EGR and clean the manifold then they should not have sent it back worse than before they started.

Robert G8RPI.
 
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Thx Robert. I will investigate the connections. Yes its the rare 2.4 20v. They were asked to swap the EGR and investigate as I had already swapped it once without it curing the problem. They refunded me but the car is worse now than when it went in. Its a garage I have used for 10 years but I have fell out with the owner/mechanic as they bumped the front bumper and denied it was them, I then found bumper paint on the fence they had parked it against.
 

g8rpi

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Thx Robert. I will investigate the connections. Yes its the rare 2.4 20v. They were asked to swap the EGR and investigate as I had already swapped it once without it curing the problem. They refunded me but the car is worse now than when it went in. Its a garage I have used for 10 years but I have fell out with the owner/mechanic as they bumped the front bumper and denied it was them, I then found bumper paint on the fence they had parked it against.

That's not good.

What was the original problem?

Robert G8RPI.
 
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EML came on due to lack of air flow through the EGR valve. When I took it off it was quite clean as for last 3 years the car has been fitted with a 4 holed blanking plate fitted between EGR and inlet manifold. I wanted to blank it off completely when I got the car 3 years ago, but I found on my previous Croma 1.9JTD that it puts the EML on if you do that. My Stilo JTD has the manifold blanked off, sending exhaust gases back into the inlet manifold is stupid IMO.
 
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The pic shows three faults, the first two are irrelevant as they seem to relate to the MAF disconnection, as it states they are stored codes, no longer present.
The red fault code is the issue. It clearly shows a problem with the turbo pressure signal. If the pressure is not fed to the ECU, it will assume no pressure, and put minimum fuel in, hence loss of power.

First, check all intake joints, especially between the turbo and engine. Then look at the turbo pressure sensor. Are the connections secure, then does the sensor seem to operate? (I've no idea what it looks like, or how it operates.) This is the area to look in, as this is what the fault codes are pointing at.
Probably a good idea to check the turbo mechanically. If it is seized, it won't produce any pressure. If its vanes fall off, you'll be glad of the goo in the manifold to catch them. (Sorry)

The goo in the manifold will only affect top end performance. Any dislodged into the cylinders will pass through without damage. They would likely be mostly destroyed during combustion, unless none occurs. If large particles go through, they will clog a DPF if fitted, but you don't have a DPF code, so don't worry about that.
 

chris3234

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That intake full of crud shows exactly why diesels are dirty cars.

On a normally aspirated diesel the intake would be far cleaner even with EGR. The problem with turbo diesels is that even a good turbo leaks oil into the intake air stream which is then mixed with the EGR soot and then settles on the cold intake surfaces.

How any government could back diesel for car usage where dynamic operation is required is a mystery. Politicians not properly researching, then being fed duff data based on out of factory data with no higher mileage/age data, etc. And if that was not enough the cheat devices cleaned up the act.
I wouldn't say a good turbo leaks oil into the inlet

I'd say it's more likely to be turbo engine have much higher levels of crankcase vapour caused by the higher pressure so more oiley vapour Gets rerouted into the manifold to be reburnt
 

s130

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I wouldn't say a good turbo leaks oil into the inlet

I'd say it's more likely to be turbo engine have much higher levels of crankcase vapour caused by the higher pressure so more oiley vapour Gets rerouted into the manifold to be reburnt

Well based on what my Croma 1.9 did, and other Fiat turbo diesel engines I have had the privilege to see up on lifts then there is (except when brand new) always oil on/in the bottom hose that goes to the intercooler. Same but less when it gets to the throttle body.

Maybe I've just seen bad examples.
 
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s130

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Regarding possible low EGR quantities.

The EGR valve input is normally fed via a corrugated cooler tube (can't recall if on the 1.9 MJet if there is any water cooling involved a well). If there are any splits in the piping from the exhaust to the EGR valve then due to loss of pressure then the EGR quantities can be substantially reduced.

Certainly worth checking the piping to rule this out.
 

chris3234

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Well based on what my Croma 1.9 did, and other Fiat turbo diesel engines I have had the privilege to see up on lifts then there is (except when brand new) always oil on/in the bottom hose that goes to the intercooler. Same but less when it gets to the throttle body.

Maybe I've just seen bad examples.

The oil is usually condensed crankcase vapour eg a mix of oil and fuel vapour
Rather then oil leaking from the turbo
 

s130

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The oil is usually condensed crankcase vapour eg a mix of oil and fuel vapour
Rather then oil leaking from the turbo

Not sure I agree? Crankcase oil fumes are normally fed into the system after the turbo. That said this does raise a question of how the engine block/sump is not under positive pressure.

I think (when I get a chance) I'll look at Croma eLearn (or other diesel turbo system) is plumed.

Regardless of turbo, no turbo then the pictures provided of that intake manifold show nothing but carbon crap build up. You do not get this with any carb or petrol injected vehicle even with EGR.

Diesel engines create soot. Even modern ones with DPF when run/booted "out of optimum range" create soot. That is why I've always maintained the diesel engines are NOT suitable for *dynamic* operation. Diesel engines are best suited, tuneable and clean when under designed constant load.

And electric car with a fixed load diesel generator can be made to be very clean burn.

Soot + oil = crud as per the pictures presented.

There is nothing wrong as such with a diesel engine when run in accordance/sympathy which what it is good at. Sadly IMHO motor vehicle as in cars is not IMHO a good use. Long haul trains, road trains, etc. then yes but not urban, semi urban stop/go etc.

If diesel was not dirty then why were DPF filters ever created?

And yes modern petrol vehicles are now having some form of filter introduced.

I fully know and accept that I'm posing a pointed (would not say biased) point of view but IMHO a huge mistake was made several years ago road haulage, agricultural, etc. diesel fuel usage was promoted to personal car usage all possibly based on some value target (eg CO) and not on overall pollution.

Bloody complex fish bowl! :)
 

chris3234

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Not sure I agree? Crankcase oil fumes are normally fed into the system after the turbo. That said this does raise a question of how the engine block/sump is not under positive pressure.

I think (when I get a chance) I'll look at Croma eLearn (or other diesel turbo system) is plumed.

Regardless of turbo, no turbo then the pictures provided of that intake manifold show nothing but carbon crap build up. You do not get this with any carb or petrol injected vehicle even with EGR.

Diesel engines create soot. Even modern ones with DPF when run/booted "out of optimum range" create soot. That is why I've always maintained the diesel engines are NOT suitable for *dynamic* operation. Diesel engines are best suited, tuneable and clean when under designed constant load.

And electric car with a fixed load diesel generator can be made to be very clean burn.

Soot + oil = crud as per the pictures presented.

There is nothing wrong as such with a diesel engine when run in accordance/sympathy which what it is good at. Sadly IMHO motor vehicle as in cars is not IMHO a good use. Long haul trains, road trains, etc. then yes but not urban, semi urban stop/go etc.

If diesel was not dirty then why were DPF filters ever created?

And yes modern petrol vehicles are now having some form of filter introduced.

I fully know and accept that I'm posing a pointed (would not say biased) point of view but IMHO a huge mistake was made several years ago road haulage, agricultural, etc. diesel fuel usage was promoted to personal car usage all possibly based on some value target (eg CO) and not on overall pollution.

Bloody complex fish bowl! :)
And your intercooler is also post turbo


And the sump is under pressure hence why you have a crankcase breather in the first place to vent the pressure and fuel out of there z
 
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