X7 C5 1.6 Hdi Boost Pressure? And Rev Range

[JM53 BEL]

I was just wondering if anyone knows what the boost pressure should be as i read that the Garret GT1544V is good for upto 150bhp engines! Also i find that my boost range aint very long but ok up higher gears! but usually seems to be within in a certain range when accelerating i would say after 3000rpm it feels like theres no help from the turbo so its like its topped out in around 750rpm

 

basically wondering if my turbo is running correctly, been trying to find out specs etc such as pressure and i would expect it to lag higher revs not mid range, going to hook up lexia see what info i can get from turbo,

[paul.h]

This is from the Citroen procedures. The pressure is measured on a gauge connected by fitting an adaptor between the turbo outlet pressure sensor and the ducting.

 

Connect the diagnostic equipment to the vehicle’s diagnostic socket.

Place the diagnostic tool in parameter measures.

Start the engine.

Engine speed (rpm) / Turbocharger pressure ( bar)

2500 rpm / 0,2 ± 0,1 bar 

4000 rpm / 0,7 ± 0,1 bar

N.B. : If there is a significant difference in the pressure read on the diagnostic tool and on the pressure gauge, replace the turbocharging pressure sensor.

If the pressure taken in the circuit is lower than the value given, check the following components :

• The turbocharger air inlet and outlet ducts
• The turbocharging air cooler inlet and outlet air ducts
• The turbocharging air cooler
• The turbocharger

If the pressure taken in the circuit (maximum 1 bar) is higher than the value given, check the turbocharger regulation system .

[coastline taxis]

The 1.6 hdi are notorious for turbo failure and if youre getting any doubts about the turbo you need to act now. Drop the sump off (very easy to do)  and check for sludgy/jellied oil also clean everything you see also remove turbo oil feed pipe and check both the pipe and the little gauze filter in the banjo bolt, rermove rocker cover and check and clean. replace the lot then put a good flush oil in then drain and put good low sulphur oil and new filter. you might be one of the lucky one that get a warning and dont think that because the milage is low it couldnt happan because it does happen. The lowest one weve done was 30k

[JM53 BEL]

Thanks guys, i will do those checks, the car has just been serviced as well lol. I have always thought the turbo felt lazy, i mean i dont expect it to be sports car accelaration but lower gear it just feels like the turbo runs out of boost pretty quick and only feels effective or descent in a certain range, 5th it pulls well on motorway but i am hesistant to overtake on bits off road were previous cars i know i could pass no issues,

[qman3428]

The turbo is a variable turbo so the boost comes in progressively rather than with a big lump at 2000 rpm. In practice theis means that the engine is difficult to tell from a 2.0 normally aspirated engine as the delivery is smooth throughout the rev range. If you are expecting the old style kick in the backside then it wont happen and you may just be expecting perfromance differnt from what the car can deliver.

Try going to a dealer and asking for a test drive, that will give you a comparision for your car.

[JM53 BEL]

I aint expecting impressive performance but what i mean is you can feel that after 3000rpm the turbo does nothing, i never really take it past 2500 but if your going to overtake thats when you notice! Just with turbo being known to fail easy way to find out if it is working correctly is by checking boost pressure! Love the car and economy and i also think for the size of engine to the car it does go very well but its just nighling at me about the turbo! As i have had a few turbo cars i have experianced turbo failure an found it to be costly last time cost me over £700 to rectify buy time i replaced turbo and flushed engine oil and coolant basically giving car full service bht that was i am strong believer in using genuine parts! Even down to oil. I could have probably done it cheaper but cheaper aint always best