Re: Renault Megane engine looses power.

When its got the problems it doesn't misfire but feels a bit uneven in its running, but certainly not missing sparks. It can just about hold idle sometimes, but often cuts out. It can rev a fair bit when not under load, but does sound rough when it does it. It generally starts OK, but needs a blip on the gas to get it going which you wouldn't normally need.

That certainly came to mind, and I did notice a rattle from under the car after the second time it did this, which certainly sounded like the exhaust. Whether it was just a bolt coming loose due to the rough running causing large vibrations, or was the cat itself falling apart.

I've taken it to my local garage today, so hopefully they'll spot the problem easily.

The garage found the fault in the cat as suspected. It had basically disintegrated, with all the debris bunging up the exhaust. So thats a fair old wedge for a new one :( . At least its a simple fault though, if an expensive one.

Give me a pre-cat car any day!

. At least its a simple fault though,

Arrghhh!!!! Picked up the car last night, clunking from under car... loose exhaust bolts or mounts or something I thought, nothing too serious. Then after a couple of miles, loss of power again! Back to the garage today, I'm not a happy man :(

Did they actually empty the exhaust system of bits from the previous cat failure?!?!

Tim..

They replaced the whole exhaust system, so I would hope all the debris would have gone with the old one! Maybe the new cat is duff?

Maybe. It certainly shouldnt rattle. Mebbe the baffles were loose, and the rattling you herd were them moving about and re-blocking the exhaust??

tim..

Found the problem at last. One of the HT coils had gone bad, so couldn't produce enough HT for a combustible spark for plugs 2 & 3. Firing on only two cylinders isn't going to make much power. It also possible all that unburnt fuel might have led to the downfall of the cat.

I drove it the 40 miles to work this morning and it seemed fine. So hopefully this little saga is over!

There seems to be more and more documentation of Renault coil packs failing, must be sourcing them from same people as VAG...!!!

Tim..