Hi folks,

 

Back to the mechanic again tomorrow but thought I'd ask here in case there's an obvious answer (searches through the forum haven't thrown up anything so far). Been having issues with my Superb for the last few weeks - started with the coil light flashing and ECU light on after the engine started intermittently running rough. Regularly serviced and no recent issues. We had very cold weather around that time - mechanic found an EGR warning and a glow plug failure - reckoned the EGR valve might have seized in the cold so wiped that and replaced the four glow plugs (said it wasn't needed until next service but figured it needed to be done anyway and wanted to start eliminating causes of the roughness). All good, drove home and took it for a few 30 km runs and all fine.

 

Then a few days later, randomly at the end of a long journey 5 min from home, engine went v rough and RPMs bounced between 500 and 1000 - lasted for a few mins and then went back to normal. Went back to mechanic and no faults logged.

 

On and off since then it fails to start as in the engine cranks and starts, bounces between 500 and 1000 rpm for a few seconds and then dies. If I come back a few hours later it can start fine and drive without issue for an hour afterwards. No further fault lights (but haven't gone back to mechanic to check fault log again yet).

 

Same thing today but I noticed some smoke from under the bonnet when it was failing to start - cranked it a few times and noticed smoke coming from the back of the engine. See attached video.

 

Anyone seen this before? Anything I should suggest to my mechanic (it'll run perfectly when I bring it back to him

Back with the mechanic today and this time it's logged an EGR valve fault - was kind of expecting that to happen at some stage (and of course its 2 months after the trust building measure expired ).

That silver band in your picture about 2cm wide connects the turbo to DPF & should be gas tight.

It's probably come loose allowing exhaust gas to escape.

 

The EGR is an expensive fix.

Or you can fit an EGR Emulator for about £100, DIY in less than 1 hour which disables the EGR & doesn't affect the DPF.

But the engine will emit more Nox, depends if you are ok with that.

Nox isn't tested during the MOT.