Fault code p0300 multiple misfire

[jakehewitt]

So went to trax yesterday, everything fine with her. Got some free injector cleaner, put that in, went on track and everything ran fine, not a hiccup. On the way home pulled off at Leicester services and filled up, then around about 20 miles past there there was a pop (I think this may have been the exhaust as it makes the same noise when I come off throttle) and car goes into limp mode, injector fault on the dash and sounds like it's only running on 2 cylinders.
Pull over, turn engine off, restart and everythings fine again. Go back on my way 2 miles on happens again. Turn off the sprintbooster, ran obd and found the fault code cleared it, left it to idle for a bit and headed back. Was fine for another 20 miles did it again, this happened over and over sometimes I would get 5 miles sometimes a bit further until about 40 miles away from my house where there wasn't another problem. I did try and recreate the problem closer to my house but couldn't.

Anyone had this? I haven't a clue what it could be, and I didn't rag her that hard round the track compared to what I'd do at hartside or the moors :/

 

[weebob]

TDC sensor or coil pack? Both of mine went at the same time and was a sod to diagnose.

 

[Foxspeed]

probably the injector cleaner playing havoc with the cat-less lambda system...

the p0300 - multi-cylinder miss fire is the sort of code that means the ecu isn't sure whats causing it...

injector cleaner and no cat could cause the second lambda to throw a wobble over the emissions!

 

[jakehewitt]

probably the injector cleaner playing havoc with the cat-less lambda system...

the p0300 - multi-cylinder miss fire is the sort of code that means the ecu isn't sure whats causing it...

injector cleaner and no cat could cause the second lambda to throw a wobble over the emissions!

I'm hoping that's what it is like, been out with it this morning trying to force another fault and nothing at all. I could feel when it was about to happen through the throttle pedal as it seemed like there was some kind of flat spot before it

 

[jakehewitt]

New tank of petrol in, just got through more than a quarter and she's still playing up :/

 

[Foxspeed]

got an obd2 reader? has it got "live" data? if it has have a look at the lambda signal should be switching fast all of the time - if its slow
then its usually a faulty sensor...

any codes thrown up?

 

[jakehewitt]

Took it to one of our step dads mates and it spat back a few more faults that I had showing on my phone :/ including 3 separate ones for misfires, one for missing cat and 2 for throttle position. He's cleared them and the car is running smoother but not getting my hopes up going for a quick run out with Mike tonight so fingers crossed