Not joined yet? Register for free and enjoy features such as alerts, private messaging and viewing latest posts and topics.

Engine Light

Discuss problems you have had or are having with your Z4
Post Reply
Cogsy_Neil
Newbie
Newbie
Posts: 2
Joined: Fri Apr 28, 2017 12:56 pm

Engine Light

Post by Cogsy_Neil » Fri Apr 28, 2017 1:11 pm

Hi,
Just purchased a 09 Z4 2.0i Sport yesterday absolutely love it although have only had one day!

On way to work today I had the engine light come on (not the EML one) no loss of power or anything, I have an OBD scanner and that has come up with a P0420 code I have since cleared it and it hasnt come back on so far. I did put £40 worth of sainsburys fuel in yesterday by the way, and car has been sat around for a while (whilst awaiting sale)

One thing that I have noticed from looking online at previous MOT's is that in 2015 it had an advisory for 'occasional missfire during emissions test' and in Feb last year the following 'emissions readings irratic'

It was mot'd recently and there were neither of those advisories present so assume they were sorted, but I understand that the P0420 code can be because of a mis-fire. How would I know if car was mis-firing? (im not mechanically minded!).

Thanks in advance for any advice etc..

Scooba_Steve
Lifer
Lifer
Posts: 5277
Joined: Wed Feb 19, 2014 3:01 pm
Location: NW London

Engine Light

Post by Scooba_Steve » Fri Apr 28, 2017 3:52 pm

If a trade sale, report and give it back to them to fix.

Petrol quality is a possibility, but a single misfire code to me would get me looking at coil and plug first in that order, obviously checking connections.
3.0si Sport: F10 Illuminated ZHP, Retrofit Cruise, OE Stubby, Gaptech RCH+, Kenwood BT73DAB + Handsfree, HIDs, LED Sidelights, OE LED Number Plate Lights, Custom LED strip bootlight.

User avatar
Ewazix
Lifer
Lifer
Posts: 4721
Joined: Sun May 02, 2010 5:30 pm
Location: Somerset

Engine Light

Post by Ewazix » Fri Apr 28, 2017 5:06 pm

Do a search of the e85/86 problems topics for "P0420 code" and you will see it's pretty common on the 2.0 in particular, sometimes simple, but unfortunately not always easy to diagnose and has driven some 2.0 owners to give up!

You may have discovered why the previous owner sold it on, if it was a trade sale you need to return it asap for verified repair or money back if it was me.
2003 2.5 SE, low miles, Sterling Grey, 108's & Eagles, no stubby here! Unmolested.
2018 Cooper S Countryman
Fiesta Ecoboost

Post Reply