Technical Ducato 2.8JTD power loss

[corsedanny]

Hello!

Seemingly, I have a braincracker issue here for the enthousiasts and technicians, I hope you can think along. I will try to explain my situation here as clear as I can.

The car:
Fiat Ducato motorhome 2.8 JTD from 2002 with about 58.000 miles / 95.000km. It has the famous long 5th gear installed. Within the last 6000 miles / 10.000km the following has been done: New oil filter, new fuel filter, new oil, new brake fluids, new brake cilinder. The car ways 3.5 ton when driving it. IT is the non variable geometry Turbo with the wastegate working on turbo pressure.

The complaint/problem:
A lack of power / power loss. I bought the car half a year ago and as this is my first motorhome, I didnt really know what to expect regarding the power of the 2.8JTD (128hp) but it felt sluggish, soapy. The dealer deliverd the car with 3.1 bar in the tires and I inflated it to 4.8 bar which has been a good improvement already. Also am I really careful with the car and try not to use full power or floor it. Usually i drive about 95km/h about 57mph i guess as a cruise speed.
After a long traffic jam on a hot summer day, the engine got quite warm but perfectly within bounderies, I noticed that after the traffic jam I had much more power and the car was picking up directly when applying throttle and felt also it 'turning off' when lifting off the throttle completely. This woke me up and now knowing it should have more power. After two weeks that I havent turned the engine on, the car was sluggish again and I started digging online as well as checking under the bonnet.

I never noticed that the car has exessive black smoke, not even in 4th gear uphill with full throttle. Internet taught me issues with the wastegate and this made me search also in that area as it feels to me as a turbo pressure issue. I have been spraying the wastegate with WD40 and used grease on the axle that goes into the Turbo housing which should open the waste gate valve. After doing this and driving with a cold engine, I feel i have more turbo pressure and power untill I demand more power from the engine like on the highways and especially after some hills on the highway. after about a 60/90 mile drive the engine has been hot and I hear the engine running less decently again, more rattling and ticking (not in a bad way, but slightly) This is always the case when i drive with power loss.

In neutral while hitting the throttle a bit, it gives a little black smoke, but in my opinion nothing special or too much. When driving i can't see any black smoke or any other colour either actually from the exhaust.. not when hitting full power in 4th gear.
To give an example, a 6% uphill on the motorway with the total weight being 3,5 ton lead to a situation where i hit full throttle in 4th gear and was hardly keeping it at 82km/h (50m/h).
When I have this power loss situation I notice a rattle as well at the switch moment from when the wheels drive the engine from the engine driving the wheels, in that area. So when from rolling, applying power again, when it should start to build up Turbo pressure let's say, it rattles.. when i apply a bit more throttle, it disappears, when lifting again till this point where i am about equal between the wheels driving the engine and the engine driving the wheels, the rattle returns.. (unless I have, what feels to me, turbo pressure and therefore power, then it doesnt seem to do this.

I have been checking the following:
- Removing a KCR box ( This is 'tuning' via a manipulation box that alters the voltages of certain sensors, in my case only fuel pressure sensor, not my kind of 'tuning' but it was installed while buying and I didnt notice ) The engine run a bit smoother without it, but this was also after i worked on the wastegate again with wb40 and grease.
- Checking for leakages, none except for one right after the air filter box (But it's the inlet part before the Turbo so i guess that doesn't make a difference, although that is now fixed and tight.
- Cleaned out airfilter and testing without a normal airfilter, But to be fair I didnt expect this to make a difference.
- Trying to losen up the wastegate.. I took off the pressure box (membrame) which is connected to the wastegate actuator, slided the wastegate fully open en closing while using WD40 to make it go as easy as possible, Fixed the pressurebox on the Turbo again, installed everything back as it should, and the power was back, but I still expect the car to have more power when it runs perfectly.
- When I had the whole actuator rod off from the wastegate today, I have been figgling with it and put my girlfriend in the passenger seat.. asked her, does this sound like the rattle we hear? Her answer was yes it does. although it's hard to compare when driving, but I am also quite convinced the rattle comes from there.
Anway, I made a video (forgive me for the Dutch speaking) where I would like to show you how the leaver of the axle that controls the wastegate goes without literally ANY resistance, it just falls down to the fully open position.. (this is with the membrame and actuator rod off which normally controls it and holds it closed)

Things to check:
- I read about a fuel tank filter that these cars have? These could also be clocked up and I would like to replace anyway. If someone has basic guidance, it would always be welcome. It would just not match up with the difference in how the engine runs after a cold start and up to the moment I have to demand some horsepower from the car with hills on motorways.
- Injector testing, but the same, it wouldn't really match up with that i lose horsepower after hills and higher demands of power from the engine.
- Could go further still as fuelpump timing etc.. but I am not sure now whether this does or does not matter with a common rail diesel engine? Besides this, why is there a difference in running with engine temps?
- Read out fault codes in the computer, but I have the 3 pinned connected and not a ODB2 connection yet.. I have a elm 327? with me and could see if it could read out something, but I would need to go from this 3 pinned connector to a odb2 connection. Any help on this is much appreciated.


Any help and thought are really much appreciated. I am thinking that the rod/axle going into the turbo housing might have snapped and every time i grease the wastegate i put it close somehow, and when i apply more power i open it so much that it doesnt close anymore and i lack power? Driving without having the power makes the car consume serious amounts of diesel..

Greetings,
Danny

 

[corsedanny]

As I couldn't find how to edit my previous post, I will make a quick post here. One tip i received is that it might be a broken EGR valve.
This is my first diesel and I am aware of the EGR valves and that they always block them off, but i am wondering if I get an EGR valve? I have no catalitic converter as far as i am aware?

 

[Communicator]

Hi corsedanny,

1. Editing. You have a 30 minute time window in which to edit your post.

2. It was only on 11th January that I mentioned on this forum that the UK company "Gendan" had been reported as helpful as regards OBD advice and adapter cables. The original poster (OP) on that thread has already reported that an adapter cable has been ordered.

3. I do not have EGR on my 2006 x244 2.8jtd, so I am not an expert in that area, but my initial thoughts was to ask if yours was the EGR version. While you may be aware that you have an EGR version, the rest of us do not. Can you please confirm whether or not you have EGR, if necesary by reference to the attached extract from Fiat eLearn.

4. Your vehicle with the 3 way OBD port is an x230 model. At lest for the following x244 model (2002-2006) there are six versions of the 2.8jtd. Two of these relate to the variable geometry turbo of the 8140.43n engine. The remaining 4 versions are with/without EGR, and subdivided into flame starter/heat flange. I understand that the heat flange is used in Nordic countries, so you could have that, but I cannot see that it could be relevant to your problem.

If EGR version then a stuck EGR valve is a possibility.

 

[corsedanny]

Hi corsedanny,

1. Editing. You have a 30 minute time window in which to edit your post.

2. It was only on 11th January that I mentioned on this forum that the UK company "Gendan" had been reported as helpful as regards OBD advice and adapter cables. The original poster (OP) on that thread has already reported that an adapter cable has been ordered.

3. I do not have EGR on my 2006 x244 2.8jtd, so I am not an expert in that area, but my initial thoughts was to ask if yours was the EGR version. While you may be aware that you have an EGR version, the rest of us do not. Can you please confirm whether or not you have EGR, if necesary by reference to the attached extract from Fiat eLearn.

4. Your vehicle with the 3 way OBD port is an x230 model. At lest for the following x244 model (2002-2006) there are six versions of the 2.8jtd. Two of these relate to the variable geometry turbo of the 8140.43n engine. The remaining 4 versions are with/without EGR, and subdivided into flame starter/heat flange. I understand that the heat flange is used in Nordic countries, so you could have that, but I cannot see that it could be relevant to your problem.

If EGR version then a stuck EGR valve is a possibility.

Thank you for your reply Communicator. I will use your logical build up to answer.

1. Thank you! I wasn't aware of that .

2. Such a cable would be really helpful if my elm can actually read something, but very much willing to try that out. I will see if I can order one and get it down here to Spain.

3. That is interesting and I guess positive that you do not have an EGR. I have just taken a look in the dark with a spotlight, but I am pretty sure that I do not have an EGR system. I see nothing behind the inlet manifold pressure sensor and nothing that looks like the drawing on the elearn that you sent with.

4. I have the 8140.43S engine and cant find the heat flange either as shown on the e-learn drawing.

As seen on the video, I have had the waste gate actuator off, moved the leaver a couple of times and havent used any grease or WD40 this time.. but I had to start the car in order to drive it on blocks, I could even then hear and feel that the engine had its power again. Although I cant be sure that it's all the power that it should have.

I have been thinking to keep the wastegate closed while driving, or maybe put it at least tighter (havent touched the setting of the wastegate yet). I am very aware that I couldn't drive especially continiously with over 1 bar of turbopressure as I believe that's what its original maximum pressure is. I guess when the engine is warm and the problem doesn't return, it must be pretty sure that it's in the wastegate? Might be too risky though on the highway in 5th gear as turbopressure might be too high and run up too quickly too high as well but be sure?

Wondering soo much if the leaver of the wastegate can literally move that easily without literally any resistance.. :/

 

[Anthony489]

Hi

By my quick calculation, driving 3500 kg up a 6% slope at 80 km/hr needs about 60 HP. Add in another 25 HP for air resistance and tyre drag and that totals 85 HP. It sounds as though your engine is well down on power, you should be able to manage nearer 100 km/hr up a 6% slope with 127 HP.

The lever on the turbo housing (attached to the wastegate flap inside) should move easily using finger pressure when the rod is disconnected, that is normal. The actuator cylinder has a rubber diaphragm and spring inside, which moves the rod when there is enough manifold pressure ("boost") to overcome the spring preload. The idea is that this gradually opens the wastegate and limits the maximum boost.

It is possible that the actuator is faulty, rubber parts do not last forever. Or the rod may be mis-adjusted. With the rod connected, the rod and wastgate flap should move steadily, it should not be possible for it to rattle about, as the diaphragm and internal spring will steady it. You might be able to apply some air pressure to the actuator from a pressure source (bicycle pump ?) via a rubber hose, and watch the operation. The correct amount of movement is quite small, maybe only 1 or 2 mm

If you replace the actuator, it is necessary to adjust the rod length. I do not know the setting for this, but it will affect the maximum boost. It might be necessary to use a temporary boost gauge to check. Or you may be able to measure boost via the OBD.

The injection system will measure the air flow, and if the air flow is low it will automatically reduce the diesel injected. So with low boost you have low air, low fuel and low power but no smoke. It will probably log a fault code.

 

[Communicator]

Hi,

I do not wish to detract from @Anthony489's excellent post, or divert you from your current line of investigation. Just to add a few facts and alternative possibilities.

If your engine does not have EGR, then it will not have a debimeter or airflow meter inserted into the outlet pipe from the air cleaner. Not so easy to see, as the EGR components.

For engines without EGR the inlet manifold air pressure is measured by the absolute pressure which is mounted/inserted into the inlet manifold close to the right hand side (RHS) of the vehicle. It is the signal from this sensor, that is used to calculate the amount of fuel injected. See attached file for picture. This sensor may have developed a fault.

To answer one of your original queries, the re is no requirement for timing of the high pressure fuel pump. After startup, all timing is obtained via the crankshaft sensor.

If as is common in the UK, your engine does not have a heat flange, then it will have a flame starter, which injects fuel into the inlet manifold, and ignites it with a single glowplug. For interesting further details see this link to Motor Roam.

 

[corsedanny]

Thank you Anthony and Communicator. All thoughts and thinking along are very welcome indeed!

Very happy with the idea of the actuator cilinder which might be faulty. It's not an easy place to reach, and it has certain clamps on the pressure hose from the turbo housing to the actuator cilinder which might be hard to get off and especially re-attach when laying under the car... but i will try this today and see if i can connect a bicycle pump to it. This also might sound plausible that after uphills and demand of power with higher pressure, it goes wrong..

As far as i can find out, i do only have a inlet manifold pressure sensor and not a airflow mass sensor, i might be wrong here, so i will make some pictures today to show.

So even thought the complete travel of the lever that is attachted to the wastegate is a approx 110 degrees, when fully openened when working correctly it should just open the slightest bit? 1 or 2 mm as you said? That sounds also very interesting as i still suspect the rattle coming from the wastegate especially because the rattle only appears when the engine just starts to propell the wheels again. Makes also sense now why the adjustment of the actuator rod comes so precise.

I will see if i can take off the connector of the inlet pressure sensor and see how it looks, possibly clean it.

I also heard about a connector issue on the injector which some 2.8's have had issues with since the day they were delivered. I will also see how this looks today.

Thanks communicator, good to know that it cant be the high pressure fuel pump.

Thanks for the thinking and great options. I will make some pictures with daylight which might clearify whether the car has an airmass meter and egr.

 

[corsedanny]

I made a little video regarding the egr, just to filter that one out.

Going to try to take off the actuator now, test it with pressure and see what happens.

 

[corsedanny]

I found some kind of sensor/valve on the beginning of the inlet manifold which has some type of small cilinder behind it. I made a picture.

Will post a video later where testibg the wastegate actuator.. seems to work perfectly fine

 

[Communicator]

I found some kind of sensor/valve on the beginning of the inlet manifold which has some type of small cilinder behind it. I made a picture.

Your pictures show the glowplug/injector, and fuel control valve for the flame start device.. The relay for the glowplug will be mounted nearby.. For more info see previously posted link to Motor Roam and scroll down.

 

[corsedanny]

Your pictures show the glowplug/injector, and fuel control valve for the flame start device.. The relay for the glowplug will be mounted nearby.. For more info see previously posted link to Motor Roam and scroll down.

I see! That is good to know, cant it have any relation to the issue of power loss? I have excluded a couple of things today i hope.

Done today:
- took the whole air inlet of before the turbo, cleaned the hoses and checked for dirtiness. Only where the carter ventilation comes in to the inlet trajectory, there was a slight bit of oil.. the rest of the hose towards the turbo was just slightly covered with black dry dust.

- felt the turbine wheel and i felt no play at all, the wheel spun freely in both directions, also does the wheel look good as far as i can judge. (Picture will follow).

- I have taken the actuator off again and tested this with a pressure pump to see what it would do. It seems completely fine to me as well. (Video will be uploaded as well).

- I checked the hose from the turbo housing towards the waste gate actuator and it looks fine without any issues. Just to be sure, as this couldnt really lead to less power i'm thinking.

- took off the inlet manifold pressure sensor connector and it looks good, sprayed it with contact spray and refitted it.

- i opened the knob on the bottom off the fuel filter to drain any possible water in there, nothing came out, even though i turned it open quite far. The filter is max 10.000 miles old, so i guess it's fine. The wires coming from the bottom side of the fuel filter didnt like me turning further.

- I have been testing by putting the wastegate just a tiny bit further, i marked the old position precisely, but i needed to know if i would feel difference. Its under even a bit more pressure in position now.

- i got the feeling that putting grease on the lever of the wastegate made the difference why i was building up pressure.. now i have left this off on purpose.

Result:
Just been driving 20km without any highway or bigger road while i warmed the engine up quite a bit before driving.. basically 0 Turbo pressure, and sometimes I feel he wants to pick it up but then it drops also basically immediatly which causes a bit of light shocking.. (dont know probably the commonly used word).

Maybe its good to mention something i noticed more with the powerbox and notice still as well now but in a lesser way.

When applying the slightest amount of throttle (lets say max 6%) i can feel it building up Turbo pressure which is also driving the car, when i press further it disappears. On the highway the same is noticable the other way around. When i am applying, lets say 50% throttle and lifting of, i feel a slight boost of power coming up when i arrive at about 10% throttle.

Also @Anthony. Have you seen the first video i posted with the wastegate lever? It has no resistance.. not a little bit, but really almost nothing. It falls down out of itself when releasing it from the actuator rod.

I have now a can of injector cleaner from liqui moly which i could tey to use for my next fill up. I hear the Turbo also whining a bit now also with warm engine.

Is it possible that the wastegate is set too tight so it loses pressure? Maybe a weird question, but i have to exclude it as it went worse now and the only difference i made it putting the wastegate a tiny bit tighter.

Tomorrow i will continue the search.. thanks communicator and anthony for your support and knowledge.

Ps.. the way i hear the Turbo whine, not loud at all but present, it gives me the feeling that it loses its pressure really quick, like with 0.1 or 0.07 bar. I am going to check all hoses after the turbo again tomorrow.

 

[Communicator]

Hi corsedanny,

I have given some more thought to your problem. Going back to basics, the ECU will cnntrol the amount of fuel injected, according to measured boost pressure, and accelerator position.

Some possible basic causes of lack of power are as follows.

1. Lack of boost pressure, which is your current line of enquiry.

2. Incorrect measurement of boost pressure due to faulty sensor.

3. Insufficient fuel rail pressure due to faulty high pressure fuel sensor or pump.

4. Faulty accelerator pedal output to ECU

5. Any other causes

It should be possible to read the boost pressure by the use of an adapter lead, and software such as Multiecuscan running on a windows computer.
The measured fuel rail pressure may also be checked in this manner.
While it should also be possible to check the accelerator by using multiecuscan, simple checks and hence elimination may also be performed with a multimeter, using resistance values taken from the attached extract from x244 eLearn.

 

[Anthony489]

Hi Corsedanny

Analog boost gauges (with pressure tube connection) can be bought in the UK for as little as £35. Is that an option for you, so you can see what is happening ? The measurement will be independent of the car's electronics.

 

[corsedanny]

Hi Corsedanny

Analog boost gauges (with pressure tube connection) can be bought in the UK for as little as £35. Is that an option for you, so you can see what is happening ? The measurement will be independent of the car's electronics.

That is very much an option for me, and something i will order indeed. The planning is to order a pressure gauge and the cable to convert from the 3 pin connector to obd2. Have to find the right time to do that.. this message is literally written from under the Ducato .

Will post later the progress of today.. following the tips and a bit more of what you and communicator wrote above. Now at the stage of measuring the potentio meter, but i lack the knowledge of how to do this.. :/

 

[corsedanny]

Well an update from my side after today:

I have taken all hoses after the turbo of the inlet trajectory off, including the 90 degrees hose to the intercooler. I cant see or find anything wrong. I have tried with an electrical pump, to build pressure in the intercooler, but wasnt so easy to make it air tight. By blowing myself i couldnt make it leak at least.

I took off all plastic covers to check the distance of the camshaft sensor, it looked good to the comparison material that i've seen. I have taken off all injector connectors, blew them out, carefully cleaned them if they werent blanc and used contact spray before putting them back. I havent turned back the waste gate actuator tention to its former setting yet, this will be done tomorrow morning.

I cleaned all hoses and closer to the intercooler the hoses had here and there some wet oil spots in them, but nothing was soaking wet and 95% it was just dark dry dust.

In total I was very impressed as everything looks in a very good condition.

I havent been able to drive yet, but after putting everything back together, i just started the engine to see if all worked well still. I didnt notice any difference but tomorrow i will test drive afyer setting back the waste gate.

I think i have found out how to test the throttle pedal potentio meter and will try this tomorrow.

Wonder how bad the injectors can really be with this mileage?

 

[corsedanny]

I found this video.. interestingly enough that lever has also no resistance at all.

If i see correctly with how much tension the diaphram would pull on the lever, thats much more than what i have.

 

[Anthony489]

Hi Danny

The spring preload in the actuator should hold the wastegate valve quite firmly shut when the engine is stopped or well below maximum boost. Here are some estimated figures:

Diaphragm diameter 5 cm
Diaphragm area 20 square cm
Boost pressure 1 Bar (above atmosphere)
Force on diaphragm 20 kilograms

If you want the wastgate to just "crack open" at 1 Bar of boost, the spring preload with the actuator installed and the rod tightened should be 20 kilograms. With engine stopped, this means that you should need to apply 20 kilograms to the rod with your fingers before it just begins to open the wastegate. Shortening the rod length will increase the preload and the boost, maybe you could test this with a spring balance (fisherman's scale) ?

Remember that these are just estimated figures, and I haven't included that the exhaust gas acting on the area of the wastegate flap will be helping it to open. However, it should be a guide to how roughly how tight the rod should be.

If you want lots of detail, see: https://www.w8ji.com/wastegate.html

 

[corsedanny]

Hi Danny

The spring preload in the actuator should hold the wastegate valve quite firmly shut when the engine is stopped or well below maximum boost. Here are some estimated figures:

Diaphragm diameter 5 cm
Diaphragm area 20 square cm
Boost pressure 1 Bar (above atmosphere)
Force on diaphragm 20 kilograms

If you want the wastgate to just "crack open" at 1 Bar of boost, the spring preload with the actuator installed and the rod tightened should be 20 kilograms. With engine stopped, this means that you should need to apply 20 kilograms to the rod with your fingers before it just begins to open the wastegate. Shortening the rod length will increase the preload and the boost, maybe you could test this with a spring balance (fisherman's scale) ?

Remember that these are just estimated figures, and I haven't included that the exhaust gas acting on the area of the wastegate flap will be helping it to open. However, it should be a guide to how roughly how tight the rod should be.

If you want lots of detail, see: https://www.w8ji.com/wastegate.html

Thank you Anthony. This is very welcome indeed. I have the exact original setting of the waste gate actuator (preload setting) but i cant be sure that it was set rightly, so i can compare it approx. at least.
I have been thinking a bit and I start to suspect the injector(s) more and more. With a cold start i can smell some diesel around the engine, with a warm engine i havent smelled anything yet. Inside the car i havent smelled anything yet either during driving or idling. If the engine has gotten warm in the traffic jam (after which i suddenly got lots more power, it might be that the material have expanded and therefor the injector sat tight again? It might explain that now since I have set the wastegate a bit tighter, the engine seemed to perform even worse as more pressure is being build up and because of faulty injectors it cant produce a decent combustion?

Yesterday I had all covers off the engine and I must say that i was surprised how clean it looked. Does it have to be dirty around the injectors when they are leaking? I am thinking to remove the injector connectors one by one when the engine is idling when warm to see if i notice differences in how the engine runs and probably vibrates. If there is one which makes hardly any difference, it might give me an indication that it is not in top shape. I will also put in the lique moly cleaner with the next fill up of the car.

I saw the price of new injectors, pff I rather have a broken turbo in that case :/

 

[corsedanny]

Has anyone perhaps a picture or video where the waste gate valve is visible in the turbo?

I found this online and would like to see the constructor of our turbo's. Mine is the mitsubishi one.



As i hear also a rattle sound (unless i put grease on the wastegate) at the moment the waste gate could start to get pressure.. it comes close to a possible conclusion of the rattle i hear as well. That would lessen my worries for the injectors and switch back to pressure loss.

Previously i set the actuator about 0.7mm tighter which (to my best comparison in hearing) increased the rattle noise a bit. Now i have set the actuator preload about 0.5mm less tight than it originally had before i started figgling.

As i have to drive today, i was planning to put the grease on again, just because i love to drive this engine when it runs at least somewhat decent.. makes it harder to compare though. Cant have to many sqeeky noises.. with people around as i am always defending the Italians brands to the bone .

I can imagine that with less pre tension, the spring pulls less hard on the waste gate valve to return and therefor less rattling...

A couple of black hands (and now telephone screen) further will provide us with some more insights after the drive .

 

[corsedanny]

Update 16/1:

What is done?
- losening the preload on the wastegate actuator, about 0.7mm from what the setting was before i touched it.
- sprayed the wastegate lever with wd40 and after i put heat resistant grease around the axle going into the turbohousing.

Result:
- the rattle is still there, but less and way less easy to hear. (Is the grease dampening the play somewhere in the wastegate?)
- the engine simply runs nicer, more smooth and also my beloved no-technical wife is noticing a less vibrating drive. (Trying my best to filter out the perception of a noisy car giving a worse total impression) trying so, i tend to agree with here although its a mistery to me how that could be possible.
- i do have more turbopressure and higher into the rev range (which should be the other way around when losening the preload on the wg actuator). I am actually pretty sure that the grease is doing this.
- the lower preload has an effect on the loudness of the rattle to my best interpretation.

Noticed during driving again:
- When having about 50% throttle, while slowly lifting this, the car feels suddenly eager to accelerate.
- when driving uphill with approx 40-50% throttle because really not much power.. while keeping the throttle pedal exactly equal and not changing it the slightest bit.. it suddenly got real power.. (in a petrol car you might say as that one spark plug started working again and the car got its power back).
- this might be an important one.. with a cold engine, i have quite some Turbo whine in the car.. more than before.. it gets less when the engine gets warm and then the turbo pressure seems also not to be there so much anymore. There seems to be a decent correlation between turbo whine and turbo pressure when driving

So overal there is simply a problem and the grease on the lever of the wg helps. But all the experiences and what i notice, cancels out what i was thinking off before and makea me go round in a circle.

What is on the planning next:
- tonight or tomorrow the potentiometer of the throttle pedal will be measured.
- start the engine with the bonnet open and unplug 1 by 1 the elec connections of the injectors. See for differences.
- start the car with me laying under it and someone hitting the throttle slightly to check for the rattle and manually hold the wastegate lever to feel and see what happens.
- get out the inlet manifold pressure sensor completely and see the state of that and clean it completely. Just trying to find out what seal is used as i can imagine the importance of having that absolutely air tight.