1. This site uses cookies. By continuing to use this site, you are agreeing to our use of cookies. Learn More.

Shudder when accelerating under modest load

Discussion in 'A6/S6/Allroad forum (C5 Chassis)' started by slabber, Feb 25, 2008.

  1. slabber
    Offline

    slabber New Member

    Joined:
    Apr 28, 2006
    Messages:
    14
    Likes Received:
    0
    [Feb 25, 2008]
    Hi Everyone!

    My 1998 2.8Q Tip runs very nicely apart from a problem that has only started since a recent service. When I accelerate under modest load (nothing harsh –speeding up when passing in to a 60 zone from a 40 zone for example, when the car is already in a high gear and with a couple of passengers or on an incline) the engine will often hesitate for a second before picking up revs with what might be described as a shudder (one, or sometimes a couple, of very short jolts or jerks). Once past this hesitation everything is normal, and under any other conditions everything is normal as well. I’m using my VAG-COM to check for error codes on a weekly basis but so far nothing.

    Just before the last service my car started to exhibit a "Load change jolt when easing off accelerator" problem (this is a service manual description), with the following error codes logged: “17953 - Throttle Valve Controller: Malfunction P1545 - 35-10 - - - Intermittent” and “17973 - Throttle Actuator (J338): Lower Stop not Reached P1565 - 35-10 - - - Intermittent”. On investigation by my garage (an independent Audi specialist) this turned out to be a hose that had disconnected from the throttle body, and my garage also cleaned the throttle body for good measure. This work fixed that problem, but now I have the new problem and I’m wondering if there is a connection.

    Since there are no error codes it looks like I will have to start replacing components, but where to begin without spending a fortune? I guess the throttle body is on the list but is there anything else – a bit cheaper - to try first?

    Any help much appreciated!

    Cheers - Graham
    #1
  2. Ads

    Ads

    [Oct 1, 2014]

  3. maxlbrown
    Offline

    maxlbrown Deep Blue

    Joined:
    Jan 26, 2006
    Messages:
    248
    Likes Received:
    0
    [Feb 26, 2008]
    May not be related but what about transmission fluid change some guys on here have found that helps with auto boxes.

    M
    #2
  4. slabber
    Offline

    slabber New Member

    Joined:
    Apr 28, 2006
    Messages:
    14
    Likes Received:
    0
    [Feb 26, 2008]
    Thanks Max. I'm pretty sure it isn't transmission. I had the fluid changed last year after a scare that I'm sure is linked to this problem in a roundabout way: I was in tip mode and changed down to second to slow the car on a steep hill and there was a MASSIVE bang! Well, my wife and I thought the tran$mi$$ion had gone for good, although it still seemed to drive okay. Taking no chances we had the car towed to our garage and had the fluid changed.

    All was well until the problem with the throttle body before the last service, and the same happened again! However, the transmission is absolutely fine - mostly smooth as silk. To me it seems like there is some gadgetry that controls all this and occasionally it goes awry.

    Hope this hasn't confuesd the issue - still looking to get the shudder sorted :)

    Cheers - Graham
    #3
  5. maxlbrown
    Offline

    maxlbrown Deep Blue

    Joined:
    Jan 26, 2006
    Messages:
    248
    Likes Received:
    0
    [Feb 27, 2008]
    Graham umm doesn't sound good. hope you get it sorted have you looked at coolant temp sensor and air temp sensor. mine was playing up hesitating and loss of power below 3k. replaced the maf made little difference, also coolant temp later and cleaned the air temp sensor in the manifold now runs perfectly.

    may be worth ten minutes. also cam sensors can cause problems.

    Max
    #4

Share This Page