Audizine - An Automotive Enthusiast Community

Results 1 to 8 of 8
  1. #1
    Senior Member Two Rings
    Join Date
    Mar 05 2013
    AZ Member #
    110740
    Location
    Seattle

    Mobile Mechanic in Kitsap Area - Misfire Diagnosis

    Guest-only advertisement. Register or Log In now!
    Looking for recommendations for a good mobile mechanic that services the Kitsap county area (Bainbridge Island, specifically).

    Coming to wits end with this misfire diagnosis and am looking for a mobile mechanic that has all the extra tools and a thorough knowledge of misfire diagnosis. I know it should be relatively simple, one of just a few things, but it keeps eluding me. I do not want someone to just come in, spend a few minutes and say oh, you need a full timing chain job. There is no rattle, the oil check valves looked fine when replaced, etc. Single cylinder 3 misfire on a B7 S4.

    Anyone know a local Scanner Danner!? https://www.youtube.com/watch?v=uB9XCDO8oa8

  2. #2
    Senior Member Two Rings DoItAllGarage's Avatar
    Join Date
    Oct 29 2013
    AZ Member #
    127509
    Location
    Bothell

    I had same misfire issues with my B8, after switching ign coil, fuel injectors, and buying new spark plugs problem still there. Did a compression test and had bad numbers. Finally, did a leakdown test and heard air in the oil dip stick tub, knew I was in trouble.

    Sent from my SM-G930V using Audizine mobile app

  3. #3
    Senior Member Two Rings
    Join Date
    Mar 05 2013
    AZ Member #
    110740
    Location
    Seattle

    Similar boat though no air through the crankcase (oil dipstick or filler), no air through coolant lines, no air coming out TB, no air noticeable from spark plug threads, no air noticeable anywhere else around the block. Only place I can actually hear escaping is from the tail pipes. Cylinder 3 had the low dry compression, fine wet compression numbers so I thought I should check another cylinder on the same bank. Since cylinder 2 came shortly after cylinder 3 in the firing order, I checked that next. TDC, same result, only air escaping out the exhaust, 90% leak rate. Makes me think the exhaust valves arent closed or Im missing something.

    Anyway, got a local (Bainbridge) shop coming on Wednesday. Grateful they were kind and patient on the phone and willing to do a house call to take a look. Going to hopefully get some more accurate or scientific diagnosis and will update here and on the proper diagnosis thread I started in the B6B7 S4 RS4 forum

  4. #4
    Senior Member Two Rings
    Join Date
    Mar 05 2013
    AZ Member #
    110740
    Location
    Seattle

    Back to looking for a mechanic, preferably one with a high speed scope, knowledge to use it, and a thorough knowledge of misfire diagnoses.

    I think the original shop that was going to come out is shying away. Talked with them Wednesday but they never came out and they haven't called back yet.

  5. #5
    Senior Member Two Rings
    Join Date
    Mar 05 2013
    AZ Member #
    110740
    Location
    Seattle

    tldr; Looking for a new mechanic to diagnose cause of hole in piston/smashed spark plug. Last week I called a local shop and arranged to have car towed there for diagnosis. They called on Friday to say there is a hole in the piston and the spark plug is smashed. This happened while under their possession of the car and now I'm stuck trying to prove it was their negligence. Need a mechanic that can assess the damage and pinpoint the cause. They are claiming it was a valve seat falling into the cylinder.

    The original mechanic to come out bailed, no showed, and no communication. I called around and couldn't find another shop to come out but landed on one that sounded like a winner, so I called a tow truck and arranged for it to be dropped off. Tuesday night, 10 hours before the tow truck was to arrive (845am) I put the spark plugs back in after the leak down test, re-attached the intake and whatnot, and then had the car towed to a local shop to diagnose the cylinder 3 misfire. They called on Friday to say that the spark plug is smashed and there is a hole in the piston. It was NOT in this condition when I dropped off the car so now I'm stuck trying to figure out what to do. They are claiming no liability, suggesting that a valve seat fell into the cylinder. I saw the valves when the IM was off earlier and all valves looked fine, though granted I didn't inspect (can I even see them?) the valve seats. When I started it up after re-installing the IM it idled more or less fine for about 90 seconds before the cylinder 3 misfire started up again, single code. A couple of restarts to check other small fixes and it did the same each time, more or less fine idle for a small bit then the single cylinder misfire would happen. It was a fine, albeit rough (misfiring) running motor when I dropped it off, and now it has a hole in the piston and "smashed" spark plug.

    I called another local shop who has done a bunch of work on the car previously and they say the valve seat falling into the cylinder is incredibly unlikely, having to get past the valves before being able to drop into the cylinder. I don't know enough about this but looking for input.

    There are a lot of inconsistencies and issues with their story so far. Such as it sounds they immediately went to trying to drive the car instead of looking at ANYTHING. The car was dropped off without a front bumper, core support minimally installed so it could be winched onto the tow truck. Vice grips clamping a hose closed, wires disconnected and dangling.

    Looking for advice before I go back and talk to them further. Currently planning on further explanation, clarity of what their ACTUAL play by play is. I also want to get an actual diagnosis of what was causing the cylinder 3 misfire. They said they think it could be the valve seat that was causing the misfire and then dropped when they took possession and caused the hole in the piston. But they didn't make it sound like that was their official diagnosis, which is what I paid for, what I contracted them to tell me. So I want them to give me their actual diagnosis of cylinder 3 - do I have a case here for them to do a tear down to find the root cause? Would I trust them? The same shop I've used before for work on the car suggested I tow the car home and have a 3rd party mechanic come take a look and do the further diagnosis on what caused the hole in the piston.

    Legal action is very unlikely due to the $$ amount. I've called insurance to see if they can help at all but not yet heard back.

  6. #6
    Senior Member Two Rings DoItAllGarage's Avatar
    Join Date
    Oct 29 2013
    AZ Member #
    127509
    Location
    Bothell

    Sorry to hear about the issues you are having. If you strongly feel they messed up, it will cost alot of time and money to prove it. My .02 , find a good low mile engine and just r&i yourself.

    Sent from my SM-N960U using Audizine mobile app

  7. #7
    Senior Member Two Rings
    Join Date
    Mar 05 2013
    AZ Member #
    110740
    Location
    Seattle

    If a 3rd party mechanic can prove that it wasn't the valve seat like they claim, and I have an eye witness of the spark plug condition the night before it was dropped off, is that not enough you're saying? I HATE feeling so helpless as a consumer. Where are any of the consumer protections? Why do businesses always get the free pass for screwing up?

  8. #8
    Senior Member Two Rings
    Join Date
    Mar 05 2013
    AZ Member #
    110740
    Location
    Seattle

    I'm just stumped because the last time I started it up (after putting IM back, new ignition coils, calibrated injectors, etc) it ran pretty good for the first minute before the misfire kicked in. Here is the link to the video.

    After this I only pulled the spark plugs to do the leak down test. I find it nearly impossible to believe that whatever was going on with cylinder 3 to cause the misfire decided that once it got to the shop was a good time to catastrophically fail. The chances of that are theoretically the same as what it would take to start a new planet. It kills me that they took the car and immediately started to drive it instead of checking ANYTHING. It came in with wires dangling, no front bumper, and vice grips on a hose. What about any of that indicates it is something you can just get in and drive without any prior checks? And the timing of the calls... First to ask about the spark plug being cross threaded, then 11min later to say the spark plug was "smashed" and a hole in the piston. It doesn't add up.

    1:20 - primed, resting PSI up to 30
    1:40 - continue priming fuel pump, resting PSI rises to about 60psi then drops to a resting point of 55psi which I believe is what it should be
    3:05 - put garage door up before starting the car, clicking noises following are me logging into VCDS and setting up some measuring blocks. PSI is staying relatively steady. Drops to ~50PSI before starting
    7:52 - start motor for first time since having removed and split IM, replaced oil check valves, cleaned/calibrated injectors, new ignition coils, etc. Started up RIGHT away and idled as expected (a bit rough) for everything that was removed and worked on. Fuel pressure was steady at 60psi while running
    8:49 - misfire begins on cylinder 3, starts running very rough just like before all of this. Put me back to square one as I thought I was doing okay with the first ~1min or so of it running.
    9:48 - turned it off



Bookmarks

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •  


    © 2001-2018 Audizine, Audizine.com, and Driverzines.com
    Audizine is an independently owned and operated automotive enthusiast community and news website.
    Audi and the Audi logo(s) are copyright/trademark Audi AG. Audizine is not endorsed by or affiliated with Audi AG.