S4 running bit flat......

[nemo2182]

Morning,
Just a quick one......I took my S4 out on friday after having left it on drive for a couple of weeks, and she seemed to be running a little flat??I had the good old MRC tune a couple of years ago now, but am wondering if it needs a little dyno run to see if it is still running how it should be. Just doesnt seem to be boosting aggressively as it has done up till now. I spoke to my mate who's a VW mechanic and he advised it could be a list of things from something as simple as being 'chocked up' to new turbo/turbos being required. Bit scared as I havent got £2500 for turbos, so I was thinking about started cheap and running some carb cleaner through or possibly 10k boost. I used 10k on my A4 1.8T and it worked wonders, but just wanted to check with the brains that know to see if this is fine to run on the S4 (Due to MAF being so sensitive) Any suggestions would be appreciated.

Nathan

 

[jonnya]

Don't know where you are in the UK but I'd get it to MRC for a health check.

 

[aragorn]

Even a vagcom scan would be a good starting point.

Its probably something like an EGT sensor has failed.

Also, i notice you've got a "dried" pipercross filter in your sig, not quite sure what you mean by dried, but if you mean you've cleaned all the oil out of it and are running it dry, it wont be filtering very well at all. The oil is there to attempt to catch stuff that the crappy filter elements dont catch. Without it you may as well drive around with some tights over the inlet.

 

[nemo2182]

aragorn,
Its not dried to the point of 'no oil', but I've heard the horror stories of MAF dying cos they get covered in filter oil. In fact, I need to prob clean it. What would you recommend I put back on after cleaning it???

Nathan

 

[Blue_Thunder]

Sounds like it's probably in limp mode (ie: won't boost about wastegate pressure).

I had this with mine last week. You need to run a Vagcom scan to identify why it's been put into limp mode (if indeed this is the case).

It's most likely a dead sensor or loose connection causing erratic readings to the ECU.

 

[aragorn]

What would you recommend I put back on...

A standard paper filter?

Craigs S4 did exactly this and there were a few fault codes stored, one of which was for the EGT sensor. We cleared the faults and power returned, the fault also didnt come back, but its probably a sign that the sensor is failing.

 

[nemo2182]

So you dont recommend the foam filters?Foam has always been my personal choice after using paper, cotton and foam. Thing is, I can clean the foam one in petrol, dry it, and chuck it back in.

 

[Dan Gliballs]

Mine's running in limp mode again this week (6psi ?). I've been resetting a lambda fault with Vagcom for several months now, but I think the sensor has finally died 'properly' and it won't reset now.

It say's "B1 S1",........is that one accessible?

Oh, paper filters all the way by the way.

 

[jonnya]

Mine's running in limp mode again this week (6psi ?). I've been resetting a lambda fault with Vagcom for several months now, but I think the sensor has finally died 'properly' and it won't reset now.

It say's "B1 S1",........is that one accessible?

Oh, paper filters all the way by the way.

They are both accessible with the right tools. You need an O2 socket (and a crows foot
for good measure) - they have a slot for the wire. It also helps to have a 'wiggle' socket
set - don't know what the professionals would call it! ;-). I've done both without breaking
anything and if I can do it, seriously, a cloven hoofed beast could do it.

 

[aragorn]

nemo: No, the only filter that actually filters properly is a paper one.

ALL after market filters be it cotton, foam, mesh etc use a very coarse filter material (ie one that doesnt filter at all) and then apply oil to the filter element in the hope that bits of dirt stick to the oil. Its a crock of ****, and best put in the bucket.

 

[Dan Gliballs]

They are both accessible with the right tools. You need an O2 socket (and a crows foot
for good measure) - they have a slot for the wire. It also helps to have a 'wiggle' socket
set - don't know what the professionals would call it! ;-). I've done both without breaking
anything and if I can do it, seriously, a cloven hoofed beast could do it.

Cheers Jonny :thumbsup:

I'll try and source one this week. Any idea how much they are from the stealers?

 

[s4marsh]

i used some penetrating fluid called fuchs anti-corrit 988 when i fitted my rs4 dp's and exhaust the other day and they were a peice of cake to move once you get the lambda socket and three miles of extension bars on them.

dan..i've just promised 2 brand new lambdas to a lad on audisrs for £25 if he needs them this week but if he doesnt and you still need them i will get my mate to send you them, but untill he gets back in touch i cant say for definate