C5 2.2Hdi Turbo Pressure

[C522]

Hello, i new and i have problem with my C5 2003 2.2HDI 98kw, diesel, manual.

Turbo pressure goes very high and engine goes limp mode.

Week ago, i change turbo with new one. Wastegate working, vacuum pipes not leaking - tested, solenoid tested and tried new one.

Diagnostic shows overboost pressure 2500mbar and then limp mode.

Old turbo has the same problem.

In idle when i press gas pedal, turbo make a loud whistle.

Does the clogged EGR valve cause the high pressure?

Fault codes:

P0235 - Turbo pressure signal; short circuit to positive or value too high

P0245 - Turbo pressure; pressure measured too high.

Maybe i get help this forum.

Sorry, for bad english.

Greetings from Estonia!

Edited January 23, 2016 by C522

[paul.h]

Welcome to the forum.

 

It could be the pressure sensor is faulty and giving a higher value than actual. You would need to check it against a pressure gauge or try another sensor. The gauge should be connected at the sensor position with a T piece so the sensor and gauge readings can be compared. The Citroen service box procedures for checking give:

 

Start the engine.

Engage the 1st gear ratio, and start the vehicle.

Engage the gears up to 3rd gear.

Decelerate to an engine speed of 1500 rpm.

Gradually accelerate , The pressure should be the following :

• 1,1 ± 0,05 bars at 2000 rpm
• 1,2 ± 0,05 bars at 3000 rpm 

 If the gauge gives the same pressure as the sensor then there could be a blockage between the turbo and engine such as the doser valve not opening  correctly. You could see what values you get first with the sensor.

 

The pressure sensor may be Citroen part no. 19207T to RPO 9701 and 1920GH from RPO 9702 but this should be checked using your car VIN. It looks to be located near the air filter.

http://www.ebay.co.uk/itm/CITROEN-PEUGEOT-2-0-2-2-HDI-INTAKE-PRESSURE-MANIFOLD-SENSOR-GENUINE-NEW-19207T-/262224232639

http://www.ebay.co.uk/itm/OE-Genuine-Citroen-C2-Peugeot-107-207-1-4-HDi-MAP-Pressure-Sensor-1920GH-/141550235851

[C522]

Thanks for reply, i try find some working car and try to replace the sensor.

[paul.h]

I edited my post after you replied to include the sensor part numbers.

[C522]

Hello again.

I bought new boost pressure sensor, but same result.

One mechanic told me the air flow meter causes the fault, engine ecu don't see airflow.

He thinks the ecu is faulty.

 

Please someone who have autocom diagnostic, can you please check the airflow, when the car is idle?

 

Thanks.

[coastline taxis]

take the car for a drive with the auto com plugged in and post a screenshot from live data please make sure you include the boost pressure

[C522]

Hello again, my autocom is broken.

I have old diagnostic scan. There is some live data, about this fault.

Autocom dont show air flow, but i dont know what program they use.

 

[paul.h]

Just a thought, has the ecu software been changed ? Have you checked all the actuator hoses for any tiny splits, maybe you could measure the vacuum in the hoses to check for leaks and if the brake servo vacuum is not lost overnight. Can the waste gate actuator be adjusted, I had to do this when replacing a turbo on a Saab. Have you checked if the doser valves are opening ?

 

A search came up with this list of possible causes of a high boost pressure:

Boost pressure too high

• Fuel system/injection feed system defective or incorrectly adjusted
• Boost pressure control swing valve/poppet valve seized in closed position
• Boost pressure-sensing pipe split or incorrectly fitted
• Wastegate actuator diaphragm split
• Wastegate actuator calibration incorrect 

[C522]

Only DPF removed the ECU.

I checked vacuum pipes, not leaking.

Maybe my autocom is faulty and not show air flow.

I search google and i found that the swirl flaps cause the high turbo pressure?

New turbo came same car and same engine. Turbo actuator move correctly and brake servo vacuum not lost.

What you mean doser valve opening?

If they like the picture, then i only check vacuum not moving.

 

[paul.h]

On the doser valve it just needs a check that the valves open.

 

On the 136 bhp 2.2 hdi the swirl flap actuator connecting plastic cup can break. This is from the Common Problems topic:

 

11. C5 2.2 hdi 136 hp only, swirl plate diaphragm actuator ball cup breaks.

      Vacuum leak/turbo fault codes (any engine).

Located at the left end of the cylinder head. Symptoms may be loss of acceleration, engine management light, increased fuel economy. The plastic ball cup may be replaced on its own (10 mins) or the complete actuator replaced (several hours DIY), about £20 but the cup is not available separately. This topic has a few notes on how to replace the part http://www.citroen-o...ragm#entry40936

 

 There is a diy fix here if not able or want to get the dealer part http://www.citroen-o...-to/#entry82945

 

I read in Car Mechanics a case where the actuator had a vacuum leak which resulted in the engine management light and limp mode and fault codes for over boost and turbo regulation fault. The slow loss of vacuum reduced it also to the turbo wastegate so turbo boost level dropped, the ecu then increased the boost control duty cycle which then deactivated the swirl control increasing the vacuum boost and tripping the EML/limp mode. These fault codes have also been reported here and it turned out to be a split in the vacuum pipe to the egr valve actuator - so any cause of a vacuum leak should be looked for before touching the turbo.