Check Engine Light / Misfires / Start Stop Errors at Random

Hi,

I recently purchased a 2013 1.2 Mk7 Golf 105 PS with approx. 55k Miles on the clock. The car has full dealer service history.

In the 6 weeks of owning it I have experienced this strange issue:
On numerous cases when starting the car in the cold, the car would rev slightly higher at around 1300 RPM with a bit of vibration before settling down to 800ish RPM after about 30 Seconds.When starting it whilst warm it will pretty much settle immediately.
Other times it wouldnt do this at all, I just assumed this to be normal for these smaller engined cars.


However on three separate occasions it would rev at 1500-1800 RPM and the car would vibrate significantly and the check engine light would flash. However after 40 seconds it would be back to normal, the idle would settle and the check engine light would switch off. The car drives perfectly normal after, (but the stop start feature switches off for the next 3 Drive Cycles).

In the first two instances, I hooked up an OBD after a couple days, and it displayed no stored or pending codes. However I left the scanner in my vehicle and when it happened the third time, I plugged the scanner in and it read p0300 Random Misfires, p0302 Misfire Cylinder 2 and p0303 Misfire Cylinder 3 in the pending codes section.

(It appears to happen when I have run the car and let it sit and then drive it again after 2-5 Hours. Although I can not say this for sure as other times when I leave it for 2-5 Hours its perfectly fine. When its left longer than 5 Hours or less than an 1 Hour it doesnt happen.)

Any ideas what could cause this? - My guess is spark plugs.
Also is the first case of high idle 1200 RPM then settling in fairly common?

Finally on a side note, Does anyone have the recommended service intervals for this variant golf which includes all the typical service items like air filters, spark plugs, oil, gear oil etc?
My previous toyota had it in the manual: where it said stuff like Replace cabin filter every 2 years or 20k manuals etc, but I can't seem to find it in my VW manual!

I had similar thing happen once but my car was warm when it happened. I would clear codes see if they come back it could be dirty fuel and if they do come back get the plugs changed if it still does it change coils. But I do think these engine are sensitive at picking up codes

Thanks for the response.

I only use BP / Shell but it could very well be a bad batch of fuel. Ill toss some redex in and add some more fuel to dilute the potentially bad fuel a bit and see how it goes. The only thing I've done out of using bp/shell regular is I tossed about £10 of premium in (as I had fuel vouchers) to 'clean the engine' in the last tank although doubt it had any effect positive or negative.


It doesn't sit as a stored code, it only remains as a pending code and then disappears all together from my simple OBD 2 scanner. Nevertheless I have cleared it as suggested. OBD Eleven is on its way for some coding, that should help shed some more light (if the problem still persists by then). As I understand it can analyse more than a typical OBD and read stored codes other scanners can't.

I had already ordered Spark Plugs and an Air Filter weeks ago when they were on 'deal' and they should be here soon. I was going to fit them regardless to do a tune up as I wanted to ensure I was getting all the power out of this engine, given that I previously drove a car with more grunt. Hopefully this solves this intermittent issue aswell, I will update this thread to help people in future.

After a couple of phone calls to dealers, I have been told in one instance the spark plugs should be changed every 2 Years or 20k Miles, in another instance I was told that they need changed every 37k miles and in another conversation I was told 40k miles. Regardless, they should've been changed by now!!
Looking into the service history it looks like all that has been done is Oil and Oil Filter Changes (at least they are honest) so guess I will need to look at the cabin filter too now! With regards to the fault: this suggests to me that its likely the spark plugs are on there way out.


Do you know what the spark plugs should be gapped to, their torque setting and what the correct service interval is?

No clue about what spark plugs or gaps or torque setting but there should be a how to guide in one of the sub forums.u should also post in the UK bit. Your obdeleven will be better and will also read live data to see if your having any miss fires. Hopefully it was just crappy fuel. Funny enough when mine did it I used a tank of she'll v power

Cose thread if possible.
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