Hi,

My petrol 2008 A4 2.0 TFSI has a thermostat stuck open, and doesn't get up to temp (90 degrees) unless I'm stuck in traffic or going slow.

It's booked in for a repair on Monday, so hopefully that will fix things. I will also ask for spark plugs to be replaced on the basis of the rich mixture affecting them.

My question is, since it's been running rich, should I clean the engine somehow? What do people think about those additives like redex?
Or, should I just forget about it and not doing anything after the repair?

No fault codes are coming up, so everything is fine apart from the engine running cool.

I am *assuming* that the engine is running rich, because it's cool - rather than a fault code telling me it's running rich. I still want to get the thermostat fixed either way.

Thanks!!
S

Think you're doing the right thing getting nthe thermostat fixed abd spark plugs, to be fair once it's done you should be ok. You can try FedEx or similar by all means but you should genuinely be ok 🙂

Hello S??

I think you are right in concluding the rich mixture is an assumption. Personally, I not a fan of changing two things at the same time, but...

Like the reference to using FedEx, Steve, but will it deliver the correct result?? 
Welcome back by the way.

Kind regards,

Gareth. 

Thanks, Gareth.

FedEx/ RedEx - Ha! 

Sammy

2 hours ago, Magnet said:

Hello S??

I think you are right in concluding the rich mixture is an assumption. Personally, I not a fan of changing two things at the same time, but...

Like the reference to using FedEx, Steve, but will it deliver the correct result?? 
Welcome back by the way.

Kind regards,

Gareth. 

Thank you Gareth 🙂 I think it can't hurt using redex I put it in my a6 occasionally

Just an update to say I had a service (all filters and oil and plugs) and the stat was replaced. Running really nice now. I will use RedEx for the next few months, can't hurt...

I've had the exact same symptoms for a good few months now, so I'll be following in similar footsteps.

The Redex debate is an interesting one. Would a combination of correct operating temperatures and long run not be better? 

Ian

1 hour ago, Ianswebb said:

I've had the exact same symptoms for a good few months now, so I'll be following in similar footsteps.

The Redex debate is an interesting one. Would a combination of correct operating temperatures and long run not be better? 

Ian

Hi Ian, 

I really don't know. I'm doing the long runs as well as the Redex (I bought a 4 pack from Costco, so I'm set for at least 6 months). But I really don't know if Redex helps.

From what I've read, it doesn't do any harm... unless someone on here has better/more proven experience with Redex? 

As it happens, I've just found a bottle in the garage! I'll throw that in when i've changed the thermostat. If for no other reason than to get rid of it!

Ian