Liam john

Today after driving for two hours on the freeway I had the CEL light pop up for the first time since owning this car for six months. It started idling rough and seemed to be miss firing intermittently at speed. I deleted the codes which cleared the CEL but it returned 15 minutes later. I drove straight home as calmly as possible.

both times my Foxwell NT710 scan tool showed the codes ...

0021 A camshaft position - system performance bank 2

0491 secondary air injection system insufficient flow bank 1

0348 camshaft position sensor 'A' circuit high bank 2

0011 a camshaft position - system performance bank 1

0030 H02S heater control circuit bank 1 sensor 1

0300 random/ multiple cylinder missfire

0301 cylinder misfire detected

0303 cylinder 3 misfire detected

0304 cylinder 4 misfire detected

I went on to look at the live data but was a bit confused as to what i was looking at.

Im not sure where to start...

Im wondering if i am:

- In for a new timing chain?
-have a leak in a vacuum hose that is letting excess oxygen into the system
-have one or a few sensors to replace
-need to replace the secondary air pump on bank one

(FYI it has a new battery)

Any help would be greatly appreciated!

Petza914

What's your alternator charging voltage. 2 hours is about the right amount of time where if the battery isn't charging the voltage would drop below the threshold that makes everything work right. I'd recharge the battery and see if the errors go away as an easy first step. You can do this using the connections under the hood rather than having to get directly to the battery again.

Liam john

Thanks Petza914. I lifted the seat and tested the battery yesterday to check charge with my battery tester and the battery was fully charged and healthy.

Tonight I have tested the front bank 1 Ho2 sensor (pre CAT) with a multimeter and fount that the heater circuit pins inside the connector don't have continuity. I did the same check with the connector for the front bank 2 and it has continuity. so that leads me to believe that i need a new front bank 1 Ho2 sensor. unfortunately I cant find one locally here in Australia so will have to wait a few weeks for shipping and then swap it out (very tight space to change but possible apparently) and see if that solves the misfiring....

Tomorrow Im hoping to check for vacuum leaks in the air pump system and see what i can find...