Page 1 of 2 12 LastLast
Results 1 to 15 of 30

Thread: Passat engine pulsing

  1. #1
    less pump-per-nickel stefan's Avatar
    Join Date
    Sep 2005
    Location
    Calgary, Canada
    Posts
    4,293

    Default Passat engine pulsing

    Hey guys,
    My 2005 Passat TDI starting having a little issue. Often, if in gear, but stopped, the engine rpm starts to pulse a bit. Maybe a little faster than once a second. Its not huge, but you can see the tach twitch, and definitley feel it.. If I put it in neutral, it stops, if I move, I no longer notice it. It happens in both drive and reverse.

    Things I have done recently include an injector purge, popped off EGR to have a look at the intake, looks fairly clean. Disconnected the MAF to see if it effected the idle, but no. Fuel filter is new. Scanned, no codes.

    I had a funny pulsing issue when I first got my Malone tune, years ago. We logged some data, and found he has an EGR setting wrong, but it also caused a pulsing, so I was wondering if the EGR could be acting up. I was also thinking about what the effects of a failing tandem pump or lift pump would be... Short of that, wondering if it could be something bigger like a torque converter or something in the auto transmission.

    Anyways, just curios if anyone had some ideas as to what else I could check.

    Much appreciated, thanks all!
    Last edited by stefan; 11-06-2017 at 10:14 PM.
    Stefan
    -> '05 Urban Grey Passat Wagon TDI. Malone 1.5, De-chained BSM.
    -> '06 Silver Mazda 5
    -> Past rides: '98 Jetta K2, '01 Jetta TDI, '91 Mazda B2200, '81 Toyota Cressida

  2. #2
    less pump-per-nickel stefan's Avatar
    Join Date
    Sep 2005
    Location
    Calgary, Canada
    Posts
    4,293

    Default Re: Passat engine pulsing

    I tried to get a video tonight but it's not acting up enough to really see at the moment. Just for reference though, I found this on YouTube and this is what it looks/sounds like.

    https://m.youtube.com/watch?feature=...&v=B0FigoWoNp4
    Last edited by stefan; 11-06-2017 at 09:49 PM.
    Stefan
    -> '05 Urban Grey Passat Wagon TDI. Malone 1.5, De-chained BSM.
    -> '06 Silver Mazda 5
    -> Past rides: '98 Jetta K2, '01 Jetta TDI, '91 Mazda B2200, '81 Toyota Cressida

  3. #3
    Registered User dJ's Avatar
    Join Date
    Apr 2007
    Location
    Calgary
    Posts
    1,019

    Default Re: Passat engine pulsing

    Sounds like fueling to me as it only happens when you first start it and evens out after a bit?
    2001 Jetta TDI GL Silver
    Malone Tune stage 5+ ,VNT17-22Turbo, OMI, PP Race Pipe, PD 150 Intake, 2 1/2" Straight back exhaust, no mufflers, 2 1/2" downpipe straight no Cat, Race 520 Injectors, 11mm Fuel Pump, Lift Pump, EGR Delete mod,DC Stage IV Clutch, Michelin X-Ice 2's, 26 lb/s of boost alll day long, Smoking like a train!

  4. #4
    less pump-per-nickel stefan's Avatar
    Join Date
    Sep 2005
    Location
    Calgary, Canada
    Posts
    4,293

    Default Re: Passat engine pulsing

    That video isn't my car. On my car it happens even when hot. Can pull up to a red light and it will start pulsing. When it's doing it, it is pretty consistent. I can sit for the length of a red light and it's pulsing the whole time. One post I read mentioned the lift pump. Wondering if that could make sense as the tandem pump isn't working as hard at low rpm, maybe lift pump is more critical at low rpm? Bit of a long shot.... Hah.
    Stefan
    -> '05 Urban Grey Passat Wagon TDI. Malone 1.5, De-chained BSM.
    -> '06 Silver Mazda 5
    -> Past rides: '98 Jetta K2, '01 Jetta TDI, '91 Mazda B2200, '81 Toyota Cressida

  5. #5
    Registered User witchcraftz's Avatar
    Join Date
    Oct 2011
    Location
    Vancouver, BC
    Posts
    2,529

    Default Re: Passat engine pulsing

    Might be a vacuum leak, did you test O2 sensor or CCV?

  6. #6
    less pump-per-nickel stefan's Avatar
    Join Date
    Sep 2005
    Location
    Calgary, Canada
    Posts
    4,293

    Default Re: Passat engine pulsing

    I am planning to check vacuum lines with a mityvac this weekend. CCV is moving air I think. Not sure how to test the O2 sensor, but I will look in to it.
    Stefan
    -> '05 Urban Grey Passat Wagon TDI. Malone 1.5, De-chained BSM.
    -> '06 Silver Mazda 5
    -> Past rides: '98 Jetta K2, '01 Jetta TDI, '91 Mazda B2200, '81 Toyota Cressida

  7. #7
    less pump-per-nickel stefan's Avatar
    Join Date
    Sep 2005
    Location
    Calgary, Canada
    Posts
    4,293

    Default Re: Passat engine pulsing

    There doesn't seem to be any vacuum leaks, and vacuum pump is pulling a lot of vacuum. I also popped out anti shudder valve and egr and ran input tests on them to make sure they were moving ok, and they seem to be.
    Stefan
    -> '05 Urban Grey Passat Wagon TDI. Malone 1.5, De-chained BSM.
    -> '06 Silver Mazda 5
    -> Past rides: '98 Jetta K2, '01 Jetta TDI, '91 Mazda B2200, '81 Toyota Cressida

  8. #8
    less pump-per-nickel stefan's Avatar
    Join Date
    Sep 2005
    Location
    Calgary, Canada
    Posts
    4,293

    Default Re: Passat engine pulsing

    Oh, I wasn't sure how to test O2 sensor, but I had another one so I swapped it in but it didn't make a difference.
    Stefan
    -> '05 Urban Grey Passat Wagon TDI. Malone 1.5, De-chained BSM.
    -> '06 Silver Mazda 5
    -> Past rides: '98 Jetta K2, '01 Jetta TDI, '91 Mazda B2200, '81 Toyota Cressida

  9. #9
    KUJI kujiwara's Avatar
    Join Date
    Jan 2013
    Location
    Northwest, Calgary,AB
    Posts
    2,200

    Default Re: Passat engine pulsing

    Check the engine and transmission mounts
    #ProjectICreate Jetta GLI 3.2 (completely stock)
    2001 Cobra#88/3786

  10. #10
    less pump-per-nickel stefan's Avatar
    Join Date
    Sep 2005
    Location
    Calgary, Canada
    Posts
    4,293

    Default Re: Passat engine pulsing

    I had time to check the main 2 mounts and they are good I believe. Engine doesn't move much with this pulsing either.
    Stefan
    -> '05 Urban Grey Passat Wagon TDI. Malone 1.5, De-chained BSM.
    -> '06 Silver Mazda 5
    -> Past rides: '98 Jetta K2, '01 Jetta TDI, '91 Mazda B2200, '81 Toyota Cressida

  11. #11
    less pump-per-nickel stefan's Avatar
    Join Date
    Sep 2005
    Location
    Calgary, Canada
    Posts
    4,293

    Default Re: Passat engine pulsing

    Pulled return line off of tandem pump today and let it run in to a jar. Getting the appropriate 1.3L per minute. So not that...
    Stefan
    -> '05 Urban Grey Passat Wagon TDI. Malone 1.5, De-chained BSM.
    -> '06 Silver Mazda 5
    -> Past rides: '98 Jetta K2, '01 Jetta TDI, '91 Mazda B2200, '81 Toyota Cressida

  12. #12
    Registered User dJ's Avatar
    Join Date
    Apr 2007
    Location
    Calgary
    Posts
    1,019

    Default Re: Passat engine pulsing

    When you're stopped have you tried pulling it out of gear and leaving it in neutral and seeing if it continues? Maybe that will give you some insight as to whether its engine or transmission related?
    2001 Jetta TDI GL Silver
    Malone Tune stage 5+ ,VNT17-22Turbo, OMI, PP Race Pipe, PD 150 Intake, 2 1/2" Straight back exhaust, no mufflers, 2 1/2" downpipe straight no Cat, Race 520 Injectors, 11mm Fuel Pump, Lift Pump, EGR Delete mod,DC Stage IV Clutch, Michelin X-Ice 2's, 26 lb/s of boost alll day long, Smoking like a train!

  13. #13
    less pump-per-nickel stefan's Avatar
    Join Date
    Sep 2005
    Location
    Calgary, Canada
    Posts
    4,293

    Default Re: Passat engine pulsing

    It levels out right away when in neutral.
    Its not super consistent, or at least the severity isn't. Sometimes it is hardly noticeable. There were a few days there where it as consistently doing it quite badly. Yesterday I didn't notice it though, this morning, it is there ,but pretty faint. So a little strange... I don't really want to book it in if I can't make it happen all the time.
    No other hiccups with transmission though, if that were the culprit. Shifts beautifully still.
    Last edited by stefan; 11-15-2017 at 09:20 AM.
    Stefan
    -> '05 Urban Grey Passat Wagon TDI. Malone 1.5, De-chained BSM.
    -> '06 Silver Mazda 5
    -> Past rides: '98 Jetta K2, '01 Jetta TDI, '91 Mazda B2200, '81 Toyota Cressida

  14. #14
    Registered User witchcraftz's Avatar
    Join Date
    Oct 2011
    Location
    Vancouver, BC
    Posts
    2,529

    Default Re: Passat engine pulsing

    You could run a can of Diesel Purge straight through the injection pump.

    Sounds like you may need to take it to a mechanic to diagnose though.
    Last edited by witchcraftz; 11-15-2017 at 12:10 PM.

  15. #15
    less pump-per-nickel stefan's Avatar
    Join Date
    Sep 2005
    Location
    Calgary, Canada
    Posts
    4,293

    Default Re: Passat engine pulsing

    Quote Originally Posted by witchcraftz View Post
    You could run a can of Diesel Purge straight through the injection pump.

    Sounds like you may need to take it to a mechanic to diagnose though.
    Yes, I have done this already. I have a little 'kit' with a jar, tubing and a little inline filter. I usually do it every year or so.
    Last edited by stefan; 11-15-2017 at 01:24 PM.
    Stefan
    -> '05 Urban Grey Passat Wagon TDI. Malone 1.5, De-chained BSM.
    -> '06 Silver Mazda 5
    -> Past rides: '98 Jetta K2, '01 Jetta TDI, '91 Mazda B2200, '81 Toyota Cressida

Thread Information

Users Browsing this Thread

There are currently 1 users browsing this thread. (0 members and 1 guests)

Posting Permissions

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