AH FabricationsEM Tuning
Results 1 to 8 of 8
  1. #1
    Neutral

    Status
    Offline
    Join Date
    Mar 2008
    Posts
    46

    Bought an Avant. Advice please.

    So, further to my earlier post, I've managed to buy one.

    It's a yellow S4 avant.

    It's all round a very nice car, with a few small problems.

    The rear bumper has had one corner touched in and it doesn't match. So I'm gonna remove it and have the whole thing re-painted.

    The car is down on power, It's a bit lacking in torque. APS have seen the car previously, and from memory say that it's a timing sensor problem on an otherwise very good car.

    I'm going to change the Hall sensor, timing belt + tensioners, and at the same time do a water pump (hopefully metal impellor type).
    Oh, and the rocker cover gaskets. Every S4 I've looked at has had a slow leak from these, so I'm not too concerned about that.

    The question I guess is. What else should I change when I'm in there?
    What else might cause the lack of power? It's had a new maf and one new lambda. Also N75 and diverter valves replaced. So I suspect it's not an air leak.

    I havn't got VAG-com to check it with, but my brother plugged in a 1551 from his audi dealership and it came up with nothing to write home about.

    So......Advicve...always welcome.

  2. # ADS
    ADS
    Join Date
    Always
    Posts
    Many
     
  3. #2
    Biglockie's Avatar
    Aye you know it makes sense

    Status
    Offline
    Join Date
    Nov 2006
    Location
    cumbria
    Posts
    1,030
    DO the work then try it for a week or two, there will be some one on here with VAG-COM near you whomight run the program for you

  4. #3
    docurley's Avatar
    Moderator

    Status
    Offline
    Join Date
    Dec 2003
    Location
    UK, London, SE
    Posts
    3,851
    Check all the pipes for any tears or leaks also it may pay to change the DV's and maybe look at the MAF as the MAFis a known problem maker on the S4's.
    Black Audi RS4 2006 Exclusive edition, Black optic option (stock for now)

  5. #4
    Blue_Thunder's Avatar
    6th Gear

    Status
    Offline
    Join Date
    Feb 2007
    Location
    Liverpool
    Posts
    1,693
    May as well do the cam belt if you're doing the water pump.

    Don't be so quick to jump to the conclusion that you haven't got a boost leak as the S4 has plenty of problem areas. Get a pressure test done on it to rule that out. If you get Vagcom, you can check the long term fuel trims, readings far from 0 on these can also indicate a boost leak.

    Common places for leaks (aside from the DV's you've mentioned) are F-hose, TBB and the intercooler end caps, although a leak can occur anywhere.

    I actually had an internal boost leak which a couple of specialists had not seen before. Turned out to be worn one-way valves which caused boost to escape out of the breather pipe back into the Y-pipe.

    Your other lambda could be duff as well. Mine has also recently had both lambdas replaced as one giving dodgy readings, however the inaccuracy was not sufficient to trigger an error code (there are quite high tolerances). Same goes for boost leaks. A fault code will sometimes only appear if the leak is significant enough to cause imminent damage.

    Welcome to the wonderful world of car induced poverty!
    Last edited by Blue_Thunder; 20th March 2008 at 14:41. Reason: Pub lunch mayd mee spel badd
    Mo power, mo problems

  6. #5
    stapo69's Avatar
    All hail the mighty quattro!

    Status
    Offline
    Join Date
    Mar 2007
    Posts
    966
    I agree, get it pressure tested, check for boost leaks, seems the next logical step. Only the other thing i've had problems with are dodgy exhaust gas temp sensors, caused mine to be down on power as a fault here knocked it back to limp mode, but I'd expect it to show a fault code for these. Where abouts are you? Someone on here might have Vagcom local to you. I'm near peterborough, cambridgeshire and I have a copy and a lead.
    MRC-Powerflex-Hotchkis-Porsche-Compomtive-Vredestein-034-JHM-Apikol-EBC-FK-Labree-Vibrant-Recaro

  7. #6
    Neutral

    Status
    Offline
    Join Date
    Mar 2008
    Posts
    46
    I'm in Northants. Just outside silverstone.

    Disconnecting the MAF makes no difference in the way the car drives, so I suspec that it's ok. Was only replaced recently though.

    Had a new hall sender recently too. But still throwing an error. So I'm more convinced now than ever that it's a problem with the way the cambelt was done, and perhaps one of the pulleys is a tooth out.

    It wasn't done by an Audi garage, so I suspect they didn't have quite the correct locking tool with which to stop them from drifting.

    Going to my Bro's audi dealership on wednesday for new brake pads and discs. And we're going to run another diagnostic on it.

    Frigging airbag light has come on again......there's a recurring theme of this in the service history. So we may have to delve deeper there.

  8. #7
    3rd Gear

    Status
    Offline
    Join Date
    Apr 2004
    Location
    Swansea, South Wales
    Posts
    528
    Quote Originally Posted by Pornstarr View Post
    Frigging airbag light has come on again......there's a recurring theme of this in the service history. So we may have to delve deeper there.
    Check the connction under the front seats. It's a common problem, happened to me. Pain that you need VAGCOM to switch it off again.
    1999 S4, MIJ Performance exhaust with 100 cell cats

  9. #8
    Neutral

    Status
    Offline
    Join Date
    Mar 2008
    Posts
    46
    plugged it into the 1551 at Audi today.

    The airbag light is the passenger side bag, high resistance. sporadic
    Gonna check the plugs, but mate says it could well be the bag itself.

    The MAF sensor is reading a 'low' fault.

    Air intake sensor is reading abnormal. sporadic.

    And what I presume to be the boost sensor/controller is reading abnormal.
    I can't remember exactly what it was called on the PC, and my bro started wiping stuff too quick for me to make note. But I presumed it to be a boost controlling valve. N75?

    Other than that, the car is clean underneath, and in decent nic. Which is nice.

 

 

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •  
Single Sign On provided by vBSSO

Garage Plus, Vendor Tools vBulletin Plugins by Drive Thru Online, Inc.

Content Relevant URLs by vBSEO