407 struggling on an Incline

[Stand-Sure]

After a bit of advice took the car to the garage yesterday, (407 07 2 litre SW sport Automatic as it’s having trouble getting above 40 on an incline it’s so much so I had to put the Hazards on it took just over 8 seconds to get from 30-40 and it was like there was no more power in it for higher speeds.

On a flat the car isn’t as bad but i need to gradually accelerate otherwise the car will rev to 3.5k then change gears

The garage found no faults when running diagnostics other than a ABS/ESP fault (need to replace sensor) is it at all possible this could be linked in some way, could the car be stuck in Limp mode at a loss here the car is only supposed to be a stop gap while I wait for a new car to be built so don't want to spend 100s for a few months.

TIA

[GiveMeABreak]

Limp mode is only triggered as a result of action by the engine ECU for obvious reasons to prevent damage if there is an issue, and this would have triggered a fault code. So not sure what diagnostics your garage are using, but if it's a professional tool, and no faults are returned, then it won't be in limp mode. Backup mode will limit engine power regardless of the situation, not just hills, so can't be that.

You haven't said if this is diesel / petrol or what engine. Sounds like a starvation problem. Either a weak fuel pump, dirty fuel filter for example.

[Stand-Sure]

Limp mode is only triggered as a result of action by the engine ECU for obvious reasons to prevent damage if there is an issue, and this would have triggered a fault code. So not sure what diagnostics your garage are using, but if it's a professional tool, and no faults are returned, then it won't be in limp mode. Backup mode will limit engine power regardless of the situation, not just hills, so can't be that.

You haven't said if this is diesel / petrol or what engine. Sounds like a starvation problem. Either a weak fuel pump, dirty fuel filter for example.

Thank you for the reply, I had a mobile mechanic out to run diagnostics and he gave me a copy of the report which should be attached to this comment (if I’ve done it right)

Apologies it is a diesel there is a lack of power on a flat IE pulling on to a roundabout it will take a while to pick up speed sitting at 15-20 for the first 5-8 seconds isn’t uncommon, taking 8 seconds to get to 20 in what’s suppose to be 0-60 in 10.1

[GiveMeABreak]

You have 2 key fault codes there:

P0299
P2562

Both these are to do with the turbo. It is likely that these are what are causing the problems as without turbo pressure, you'll have no boost - especially on an incline.

The Gearbox faults will be because of the wheel speed sensor. That info is used by the ESP ECU to advise the engine ECU and the Gearbox ECU and other vehicle systems of the vehicle road speed, so is essential you get that sorted as you'll have no cruise control or ESP functionality with that fault and will continue to get gearbox warnings.

If you have your VIN, pop that up and I can relate the fault codes above to your engine specifically. Please post your VIN in full without spaces - it will be automatically masked from public view after submitting your post & will only be visible to staff.

[Stand-Sure]

You have 2 key fault codes there:

P0299
P2562

Both these are to do with the turbo. It is likely that these are what are causing the problems as without turbo pressure, you'll have no boost - especially on an incline.

The Gearbox faults will be because of the wheel speed sensor. That info is used by the ESP ECU to advise the engine ECU and the Gearbox ECU and other vehicle systems of the vehicle road speed, so is essential you get that sorted as you'll have no cruise control or ESP functionality with that fault and will continue to get gearbox warnings.

If you have your VIN, pop that up and I can relate the fault codes above to your engine specifically. Please post your VIN in full without spaces - it will be automatically masked from public view after submitting your post & will only be visible to staff.

That makes sense thank you for laying it out for me the guy working on it who I bought it from said they had a mechanic out that claimed to have snipped the wires to the sensors at the front relating to the ABS I’d now assume that it’s what’s causing the ABS/ESP ECU Transmission faults

The mobile mechanic that came out noted that the sensors at the front were working as he was getting live data when he was moving them independently and when he drove back and forward it was just the rear passenger (left) that appeared to have been worn by some dirt/debris coming into contact

He inspected the wheels one by one too

My VIN is VF3**************[VIN obfuscated, can be read by forum staff]

[GiveMeABreak]

Ok so here are the main faults to address in addition to the Wheel Speed Sesnor. This system should be the Siemens SID803 Injection System according to your VIN, so these fault code descriptors apply:

Fault Code:	P0299
Description of Fault:	Turbocharger pressure signal: Pressure too low in relation to the reference value. Difference negative for 10 seconds, between the turbo pressure reference and the measured turbo pressure: The turbocharger pressure is below 800 mbars at the reference point, for an external temperature of 20 °C and at an altitude of 0m. Conditions of activation of the diagnostics - Engine speed above 1000 rpm - The actual engine torque is higher than 70 Nm
Conditions for Fault to clear:	Driving for 5 minutes
Downgrade Modes whilst Fault is active:	Downgrade ASR mode (Torque limitation for traction control) Deactivation of the ASR (Wheel anti-skid ) Deactivation speed limiter until the next time the ignition is switched on Deactivation of the speed limiter Deactivation of the cruise control Deactivation cruise control until the next time the ignition is switched on Closing of the EGR (exhaust gas recycling) valve
Symptoms:	Lack of power Noise Smoke from the exhaust
Suspect Areas:	Air meter restricted Clogged air filter Obstacle obstructing the air passage Air lock between compressor and engine Turbocharging pressure sensor Turbocharger position copy sensor Vacuum problem Turbocharger

Fault Code:	P2562
Description of Fault:	Turbo position copy signal fault: Positive gap between the reference turbo position and the position measured. The fault is forwarded if the difference between the reference value is above 30% at the actual position (For at least 8 seconds) Conditions of activation of the diagnostics - Engine speed above 1500 rpm - Engine torque higher than 120Nm
Conditions for Fault to clear:	Driving for 5 minutes
Downgrade Modes whilst Fault is active:	Inhibition of the flowmeter plausibility faults Torque limitation for traction control Deactivation of forced regeneration of the particle filter by the diagnostic tool
Symptoms:	Lack of power Noise Smoke from the exhaust
Suspect Areas:	Turbocharger position copy sensor Electrical harness Connector Vacuum problem The variable geometry of the turbocharger is locked Particle filter Air metering valve

[Stand-Sure]

Brilliant thank you this information I’ll show the garage this so they know where to begin, I took in yesterday for them to look at and they focused solely on the ABS instead of the power loss

I don’t suppose you’re able to find out what colour connector would be needed for the ABS sensor using the VIN?

Fully appreciate your help here

[GiveMeABreak]

Not sure what you are asking regarding colour connector? - if the wheel speed sensor is damaged it needs replacing and the whole sensor and cable it is attached to plugs into the static harness when fitted.

[Stand-Sure]

Not sure what you are asking regarding colour connector? - if the wheel speed sensor is damaged it needs replacing and the whole sensor and cable it is attached to plugs into the static harness when fitted.

Apologies not a car person myself learning as I go along, I was told that there are different coloured connectors as a part of the ABS sensor

[GiveMeABreak]

We only use official parts from PSA, which would bring up the correct part number for your vehicle.

We can help if you need an original, genuine part number or part diagram, and can't already find the info you need on the Forum. For this service, we do ask for a membership upgrade for official parts data as we are in turn charged for this. It will cover you for future part number requests for up to 2 years, so excellent value.

If interested, links are below, then provide your vehicle's VIN in full, which will be masked automatically when you submit your post.

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[Stand-Sure]

Completely understandable if I have issues I’ll look to upgrade as I’m only going to keep this car for a few months

I fully appreciate your time and effort and thank you again

[PaulC5]

I had P0299 on our C5 and that was a bunged up MAP sensor. It was blocked with oil/carbon. I tried cleaning it with carb cleaner which worked to improve acceleration but then brought up other fault codes so in the end a new one cured it. I found it by looking at live data from the sensor which barely moved when the accelerator pedal was used.

[Stand-Sure]

I had P0299 on our C5 and that was a bunged up MAP sensor. It was blocked with oil/carbon. I tried cleaning it with carb cleaner which worked to improve acceleration but then brought up other fault codes so in the end a new one cured it. I found it by looking at live data from the sensor which barely moved when the accelerator pedal was used.

I have read this as being quite a common issue, with mine it’s generally ok on flats and gentle inclines where I can put light to moderate pressure on the pedal but for steeper inclines it’s just no good was it a cheap fix?

[PaulC5]

Checking the MAP sensor cost nothing, I simply plugged in my code reader and looked at live data. Then removed the sensor and could see it was bunged up. New ones are available at a range of prices but I went for a mid price Delphi one from one of eurocarparts websites (they have a few under different names but the parts can be returned/swapped at a eurocarparts shop).

[Rp0thejester]

I think the MAF should be the first check after the issues I had, sounds similar, just disconnect the cable and see how she runs then.