gav86

Hi guys, I was wondering if someone might have more of an idea than me on this issue. My work runaround is a 2011 Vw polo 1.2 petrol (3 pot).

Abo​​ut 6 weeks ago I did a long journey back from a meeting in the north. On return to sheffield, the engine started to run very rough on idle and randomly loose power through the Rev range. Sometimes a sharp increase in revs out of gear would solve it sometimes not. That evening I switched the spark plugs and that seemed to solve it... until today!

Today I had to get over to Liverpool and around Glossop it started to randomly drop power through the revs and again a very rough idle. So after the meeting I visited ECPs and purchased some new coil packs. No problems, until I hit Glossop on the way home and yet again the same issue reared it's ugly head again. (yes I should just avoid Glossop altogether). I also put an injector cleaner through the system about 2 tanks ago.

Anyhoot, does anyone have any ideas of what the issue could be before I book it into my local tomorrow?

Thanks

gav86

Update - diagnostics say a faulty lambda sensor... Anyone more mechanically minded than me think this could be the cause of the issue?

​​​​£264 to replace...

Than​​​​​ks

unclefester

Wiring loom - always check that first.

johnckeen

Buy a lambda from euro and fit it yourself... or is that the price to buy it? If it was a faulty lambda it would make it run rough but I'm pretty sure it would flag the engine management light.

nomadicS2k

Second hand one off ebay? Sounds like some characteristics from a faulty Map sensor?

gav86

Thank, no lights on the dash at any time which does strike me as odd.

​​​Also after the car has sat, it runs fine, looks like it only happens after about 2 hrs of driving

unclefester

So something is getting hot and unhappy. I say again, are you sure you don't have a wiring issue or perhaps an earth that comes loose as things get warmer?

gaddafi

code reader has to be the first step

a dodgy lambda will 'always' throw a code

I doubt a car is any hotter after two hours than it is after 30 minutes assuming normal driving

so I suspect the timing is coincidence

gav86

I took a look at the wiring under the bonnet this morning before heading to work. Nothing looked obviously wrong, but I didn't get chance to check the battery terminals - overlooked it to be honest. I will check that in the morning.

A​​​​​s code reader stated lamda was an issue, I will probably change that and then see what the next code is if any.

Thanks so far, will keep you posted on progress.

gav86

Well... Lamda sensor changed and diagnostics shows no more faults. Hopefully that will have solved it.

Checked the battery connections and all was tight.

I guess only time will tell! Thanks for all advice