Vw Polo 1.2 AWY 2003 - failed NCT, cannot hold revs between 2.5K & 3K #
Posted by Fiachra Purcell on February 12, 2014, 2:07 pm
Year of Manufacture *: 2003 Engine Size and Code *: 1.2 AWY ( Optional ) ECU Type: Siemens ( Optional ) Scanner Used: Autologic, VCDS
Hi all. I have this Polo that has failed NCT (our version of the MOT) because they cannot hold the revs between 2.5K and 3K (car wont pass anyway it needs a proper cat). I know these 1.2 engines are hard to keep steady but this car jumps straight from 2.4K to 3.8K Previous garage has replaced throttle body and both lambdas and a (spurious)catalytic converter . I have checked everything.There are no fault codes. Cam timing verified using WPS, MAP sensor verified vs actual manifold vacuum. Smoke tested manifold. Load tested all wiring associated with engine control. I updated the engine control unit to the latest software. Checked another car (Fabia 1.2 AWY), it was similar. Our VW dealer reckons they have never come across this. I am just wondering if anyone else has seen this issue or better again cured this fault? Regards Fiachra
Re: Vw Polo
Posted by Richard Endean on February 12, 2014, 4:29 pm, in reply to "Vw Polo" Richard Endean
Just a thought - have you tried doing it with the front wheels running in the brake test rollers? I think this works on some Rovers with similar issues.
Re: Vw Polo
Posted by george ambelas on February 12, 2014, 9:07 pm, in reply to "Re: Vw Polo" George Ambelas
I would check the accelerator pedal sensor output voltages with an oscilloscope if I were you
Re: Vw Polo
Posted by Samantha Smith on February 13, 2014, 10:06 am, in reply to "Re: Vw Polo" Samantha Smith
I have found a common problem when V.W's do this that there is an air leak on the system which in turns means that it will not pass an emissions test.
Re: Vw Polo
Posted by Fiachra Purcell on February 15, 2014, 6:38 pm, in reply to "Re: Vw Polo" Fiachra Purcell
Hi all. I tried loading the engine with all the electrics on, It was still the same. I also tried doing it in gear on the ramp. This was better but still very hard to keep steady. Garage has now taken it back. They are going to replace the cat again with a genuine one this time. NCT have said they will pass it if the emissions are ok at 3.8k. Thanks for all the replies.
on February 12, 2014, 4:29 pm, in reply to "