Notices
 
 

  

User Tag List

Thread: ALT Engine Difficulty Starting

Results 1 to 1 of 1
  1. ALT Engine Difficulty Starting 
    #1
    Join Date
    Dec 2008
    Posts
    81
    Post Thanks / Like
    Mentioned
    0 Post(s)
    Tagged
    0 Thread(s)
    Quoted
    14 Post(s)
    Hi all,

    Thoughts please, 04 Passat, 2.0 ALT petrol engine, 96,000 miles.

    Had this one a few years now (my third B5/5.5 20 valve petrol), do about 15,000 miles a year and do my own servicing and simpler repairs. Coming up for a service again according to the dash warning, had an oil change service last August and full fluids, filters and plugs the service before. I replaced the fuel pump about a year ago, it was intermittently not running and requiring a "tap" on it or the tank to wake it up, been fine ever since up until yesterday morning. It always starts instantly but took 10-15 attempts to start the car, surprised but I put it down to flooding, had that occasionally in the past if these cars are just moved on or off the driveway and the weather has been chilly. When I left work last night same problem, although it "only" took 4 attempts to get it going. scanned it with VCDS when I got home, no engine related codes and no warning lights. Once started it runs as normal, pulls well, idles smoothly, no hunting and no overshoot when dropping down to idle speed. I did wonder whether I had a head gasket problem with water getting in the cylinders (been there, done that, but not on these) but the level in the expansion tank looks good and it's still a nice pink colour.

    However...........one thing I noticed this morning is that when it eventually starts it doesn't idle at around 1200 rpm and then gradually reduce down to 750 as it warms. it idles at 750 straight away. Thinking back to yesterday, it did the same then, I noticed the engine was quieter but didn't register why. Once warm it starts on the first turn of the key, as I proved last night when I got home.

    My first thought is the green temperature sender at the back of the engine, had a leaking O ring there years ago and replaced it with a £10 one of eBay. If I remember correctly it has 4 wires (2 sensors), one for the temperature gauge (which is working fine) and one for the ECU. Could a faulty one of these really cause such difficult starting, I find it hard to believe but it's the obvious first thing to try I guess.

    Does anybody have any other thoughts, suggestions?

    Thanks in advance.

    Ian

    Temperature sensor changed this morning. Checking with a multmeter one of the 2 thermistors had a considerably lower resistance (2300 ohm v 3300 ohm) on the new one compared to the one I took out. Might be a coincidence but car currently starts perfectly every time, idle speed 1200 then drops to 750 rpm after about 30 seconds. Will try it tonight when the temperature drops, here's hoping.
    Last edited by ianhayter; 27-02-2019 at 02:00 PM.
     
    0 0 0
     

Similar Threads

  1. Please Help 2.0 TDI Sport Touran - Difficulty Starting
    By caribsimon in forum Touran - Sharan - Caravelle
    Replies: 1
    Last Post: 03-06-2017, 11:53 PM
  2. 1.8T difficulty starting
    By acmo in forum Audi A4 - B5 Forum - 1995 - 2002
    Replies: 2
    Last Post: 09-07-2011, 07:58 PM
  3. Difficulty in starting and instrument /
    By headache56 in forum Passat - B5 Forum - 1997 -2005
    Replies: 1
    Last Post: 22-06-2008, 10:24 PM
  4. Suden error code 17978 and difficulty in starting
    By headache56 in forum Passat - B5 Forum - 1997 -2005
    Replies: 2
    Last Post: 31-03-2008, 04:48 PM
  5. Difficulty starting and rough running when engine is cold
    By brauser rexel in forum Archive posts
    Replies: 4
    Last Post: 23-10-2007, 04:50 PM
Bookmarks
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
  •  


 



  


Disclaimer: VW Audi Forum is an "independant enthusiast website", administered in line with guidelines supplied by VAG in the UK, and is in no way related to any of the Worldwide Volkswagen,Audi,Seat,Skoda,Bentley,Bugatti,Porsche or Lamborghini group of Companies. For official up to date information on any of there vehicles, please visit the official websites. Any comments made throughout this website, are the views of the respective poster, and in no way represent the views of the VW Audi Forum Administration, or the worldwide Volkswagen & Audi Group of companies.


VW Audi Forum do not vet and are not responsible for any information which is posted in this forum. All content is viewed and used by you at your own risk and we do not warrant the accuracy or reliability of any of the information.


Copyright: Certain "words", "phrases" and "Images" used on this website by the Administration are "Copyright" of Volkswagen GB, Volkswagen AG (Germany), Audi GB, Audi AG (Germany), Volkswagen Motorsport GB, Volkswagen Motorsport AG (Germany), Audi Motorsport AG (Germany), Volkswagen Racing GB, Bentley, Bugatti, Porsche and Lamborghini. No image can be replicated by anyone WITHOUT the relevant Companies written permission.


All trademarks and copyrights remain property of their respective owners.

No part of the VW Audi Forum website or forum may be reproduced without written permission from the site administration


PLEASE NOTE - PERSONAL ABUSE, ABUSE AGAINST THIS OR ANY OTHER WEBSITE OR ANY COMPANY WILL NOT BE TOLERATED. OFFENDERS WILL BE MODERATED OR EVEN BANNED.


This website and forum are best viewed at a minimum resolution of 1024 by 768.



  



- VW AUDI Forum - The #1 Volkswagen (VW) Group Forum - Volkswagen (VW) - Audi - Seat - Skoda - Bentley - Bugatti - Lamborghini - Porsche - Scania - MAN - Ducatti - VW Audi Forum -


- www.vwaudiforum.co.uk - www.vwaudiforum.co.uk -