AOwen

🙂 In those days a Renault 4 only had about a dozen wires. Vehicle technology has accelerated hugely in the last few decades. 20 years ago I was writing computer code to solve 3D Navier-Stokes equations; now I have to ask my kids how to use MS Teams!

All, thanks for your time. Problem solved, well at least found, small split underneath in the short rubber pipe immediately after the turbo. You were right all along about checking for leaks, it was the "throttle" position that was bugging me, but that's really just for the EGR process. Last time I did serious commercial car spannering we were really chuffed to have central door locking! Things have moved on.

Where does the air intake temperature get picked up? Mine is showing ambient T at 10 deg but intake T at 23 deg, should they be similar?

I've had the car since it was 9 months old and it's never been modded for anything. The OBD2 seems to think the EGR is OK. No other faults are raised, just the air leak. I guess that the throttle actuation not changing suggests that the EGR is not being activated?

Apologies, it's difficult to include everything! 🙂 PCV is clear, the valve diaphragm is good, she's breathing a little heavily but not too bad. 3 days ago it took about 10 miles for the ECU to register the "Air Leak" fault, now it takes about 200 yards, so whatever it is has clearly got worse. Do these engines have "favourite" leaky bits or is it just random?

The throttle body is clean. If I disconnect the actuator the OBD picks it up, the MAF and MAP sensors are giving sensible values. I'm going for the air leaks, the throttle may be a red herring? But I cannot find a leak anywhere. Is there a possibility that the MAF sensor may be giving what appear to be sensible values but actually incorrect when the ECU compares actual airflow? BTW, how does it calculate the dfference between MAF values and actual?

Yes, actual =88% and commanded = 95% all the time, load, idle, ign on but not running, never changes

Thanks @AnnoyingPentium I am a Mech Eng and used to solving logic problems, but this one just doesn't! 🙂

Just a thought, if the pedal position is reporting 88% constantly (i.e. full throttle) shouldn't the engine be revving it's little nuts off? Where does the system know to ignore the pedal position signal ?🤔

Yes, it's surprising that given the plethora of information from OBD2 systems, there are still huge gaps in diagnosis 🤔

Yes, I'm thinking it's a trial and error job 🙂 I can't find any logical solution from the information that I have. 😖

No, with the faults cleared it drives the same as usual. Starts/Stops fine, normal MPG is difficult to gauge. Following the TV advert theme, unfortunately, at present " Other Fabia's are not available!"

Absolute pedal position varies from 12% at idle to 80% at full throttle

PS. The pedal position varies as it should, MAF/O2 rates are OK

Hi. Fabia 1.6TDI 2011, 133,000 miles, gives me P2279 Intake air leak error code. I can't find any leaks, but the OBD2 scanner shows the throttle position as 88.6% constantly, even at idle and the throttle actuator at 95%, also constantly. If I clear the codes and drive it hard, it will go for miles without any problem, but as soon as I slow down it throws the fault and drops into limp mode. I am assuming that this process means that as long as everything else agrees with the throttle position, it's happy? Would the throttle position fault create sufficient airflow confusion to the rest of the system to create the P2279 fault or can anyone suggest an alternative possibility? I can't find anything online that corresponds with this issue. Thanks for any suggestions.