Engine sputtering and smell through vents

Hi all,

I have a 2012 hybrid Auris and for the past few months I’ve noticed an intermittent sputtering noise coming from the engine and exhaust. This is always associated with a bad smell, almost like burning fuel, coming through the vents when the noise starts. I’ve taken it to the mechanic but each time, the noise has stopped once I arrive there so no cause has been found.

- I’ve noted the noise generally starts after driving in high RPM for a while, I.e. reaching the top of a hill or travelling at a higher speed and RPM

- the car starts to shake and shudder, more noticeable when idle, and feels like the engine will cut out at any moment.

- when idle, the exhaust sounds like a terrible muffler on a modified car

- the noise disappears when the car switches into electric/battery mode

Any help would be appreciated please!

Thank you!

Hi, 

what is the mileage of the car?

The engine seems to misfire and cause clutch knocking sound. 
You need to look on egr system cleaning. Egr valve, pipe, cooler, intake manifold, and throttle body. 
Can do a service too if haven’t done any in the last 12 months. Oil, filters, spark plug if needed, coolant both inverter and engine. 

Sounds like the flexible flywheel plate which attaches the engine to gearbox

Is it like below?

Thank you both!

@TonyHSD the mileage is 66,000 and it’s due a service in a month so I’ll definitely get that done. 

@solero thanks for that post, yes the noise is very similar if not exactly the same as that (not as severe though). Hopefully it’s audible in the video I’ve posted in the original post. 

You might be able to see misfire data, or data in general using scanner or techstream so you'd have more idea of what you're chasing, there's many causes for misfires 

Mileage not too high but it’s an old car si egr system defined needs cleaning. 
What petrol do you use? 
Best for thee cars is E5 97 from bp or Shell v power . Try to avoid supermarkets. 

Thanks for that! I normally use either Esso or Costco E10 petrol