1. This site uses cookies. By continuing to use this site, you are agreeing to our use of cookies. Learn More.
  2. Welcome To LandyZone!

    LandyZone is the biggest Land Rover forum on the net. We have plenty of very knowledgable members so if you have any questions about your Land Rover or just want to connect with other Landy owners, you're in the right place.

    Registering is free and easy just click here, we hope to see you on the forums soon!

Td5 uneven idle (video) – Solved

Discussion in 'Defender 90 / 110 / 130' started by cnobel, Nov 23, 2016.

< Previous Thread | Next Thread >
  1. cnobel

    cnobel New Member

    Joined:
    Nov 22, 2016
    Posts:
    4
    Likes Received:
    1
    Location:
    Denmark
    Hello everyone,

    Completely new user on the forum here, first post, also a relatively new owner of a 90 Td5 from 2000 with 230k kms on the clock. I've been looking all over the net in order to find a solution to a suddenly occurring weird idle issue of my Defender, now i've come to you and i would be very happy if you could help me out with this!

    Problem is that idle speed suddenly rises, and then stays there for a while until dropping drastically into almost a stall, and then back to normal or a new almost stall that results in a rise. This goes on and on until it suddenly just goes back to normal again and stays there for the rest of the trip (mostly - it's pretty random actually)... Intervals can be both very long and not very noticeable or short and more violent, like the good old defender is pretending to be on the start grid in a fast and the furious movie (slight exaggeration!)

    It's happening after a few kilometers driven and persist for about 15-30 minutes whenever i drive slowly without giving gas (no matter which gear, and of course the car moves faster when it occurs) or are stopping at a light. After 30 mins or a long drive without stops it's mostly gone. It happens mostly when weather is cold, but also when warm. It doesn't seem to have anything to do with how it's driven, and then sometimes the clutch pedal seems to affect it all of a sudden.

    In the video below, which isn't the best of examples because it doesn't shift in idle speed as much as other times, revs are higher than normal and a bit rough, then i press the clutch and idle speed shifts to normal and then rises again shortly after (clutch still down). I've had the glow plugs checked and serviced and the wiring loom seemed in good condition. Also the red plug are completely dry without any residues of oil or dirt. I couldn't really explain the problem to the mechanic since it didn't occur at the moment i was there - of course - but he did tell me that it could be a problem with the fuel pump. The pump is running silent and smooth though... Have this problem occurred to any of you before? If so, i would really appreciate some good advice!

    Aside from guessing there must be some kind of problem that needs resolving, it's a problem because it seems to disturb smooth gearshifts and It's also very annoying sitting at the traffic lights with an engine sounding like i kind of want to race the car next to :rolleyes:



    Thank you!
     
  2. Wimblowdriver

    Wimblowdriver Well-Known Member

    Joined:
    Aug 3, 2014
    Posts:
    960
    Likes Received:
    591
    Location:
    uk
    I don't know much about TD5's but assume the engine management system is similar to the later tdci. If it is you might have a problem with some of the sensors or associated wiring. Reason I think this is that on the tdci, there is sensor on the clutch hydraulics which activates when the pedal is pushed and sends a signal to the management system to reduce torque during a gear change. Similarly there is a sensor on the brake hydraulics that reduces engine power during braking. Might be worth plugging into a diagnostics to identify which areas to investigate?
     
  3. lightning

    lightning Well-Known Member

    Joined:
    Aug 19, 2006
    Posts:
    2,136
    Likes Received:
    330
    Location:
    High Peak
    I had similar running issues with a 2003 TD5.
    It was solved by replacing the injector harness, even though there was no oil at the red plug under the seat.
    Might be worth a try. The part is cheap and easy to change....it's almost a service item!
     
  4. cnobel

    cnobel New Member

    Joined:
    Nov 22, 2016
    Posts:
    4
    Likes Received:
    1
    Location:
    Denmark
    Thanks for the replies!

    I haven't thought about these sensors, i'm gonna have to figure out where to access them and have a look, especially the clutch one sounds interesting to check out! The diagnose must be the next time im in the shop, thanks!

    Well if this is fairly DIY friendly i can't see why i shouldn't try this as well, thanks!
     
  5. cnobel

    cnobel New Member

    Joined:
    Nov 22, 2016
    Posts:
    4
    Likes Received:
    1
    Location:
    Denmark
    Update: Problem solved!

    I always thought that the water temp gauge was just a passive instrument, thus i haven't really done anything about it only occasionally working - not even mention it in this thread. But while reading about all the various sensors in the TD5 engine as proposed, i discovered that the temp sensor not just feeds the gauge, but that the signal visits the ECU before being sent to the gauge. I then changed the temp-sensor to a new one after diagnosing that nothing else seemed to disrupt the signal. Since that, not only has the gauge been working (which is nice), the engine has been running smoother than ever with absolutely no sign of the previous idle changes. Fantastic!
     
    neilly likes this.
  6. Kwakerman

    Kwakerman Well-Known Member

    Joined:
    Jan 19, 2013
    Posts:
    3,276
    Likes Received:
    507
    Location:
    Hampshire
    You may even find your mpg improves, if the ECU is thinking the engine is cold it may be increasing the amount of fuel being injected as it would do on a cold start.
     
  7. cnobel

    cnobel New Member

    Joined:
    Nov 22, 2016
    Posts:
    4
    Likes Received:
    1
    Location:
    Denmark
    Sounds great, i hope! Those cold starts is another problem though – it's still really bad at starting in the mornings during the winter months. But there are plenty threads to read on that issue!
     
< Previous Thread | Next Thread >