85 505 GTi puzzle
  • Register
  • Help
Results 1 to 3 of 3
  1. #1
    Fellow Frogger!
    Join Date
    Aug 2001
    Location
    Tamworth
    Posts
    150

    85 505 GTi puzzle

    I have been puzzling over a problem with my GTi. There seems to be an inordinate amount of gas escaping from the rocker cover when the oil cap is off. There is always oil seeping out from under the oil cap. On a recent trip, the crankase hose, on the rocker cover, blew off. Here are the symptoms:

    . The air is clear, and not hot, so suspect it isn't exhaust gas

    . EGR valve is working

    . Tube to bottom of crankcase is clear, as is the entrance to the crankcase. There was a small amount of gunk inside the crankcase but not enough to block it

    . Same tube from crankcase has a slight vacuum

    . Plumbing from rocker to air intake is clear including the channel in top of rocker

    . Burns very little oil

    Advertisement


    . No oil leaks anywhere, apart from seepage under the oil cap. Crankshaft, dizzy, and cam seals replaced recently.

    Otherwise, the car runs very well but this high pressure under the rocker has got me tossed.

    Any ideas?

    Cheers,
    Cheers,
    Brodie

    '78 604 SL (LPG) ...........for sale ..sold
    '81 604 SL (spares) .......for sale ..sold
    '85 505 GTi ..................for sale ..sold
    '94 405 SRDT............... for sale ..sold
    '07 307 HDi hatch
    '07 307 HDi Wagon

  2. #2
    1000+ Posts Rod Hagen's Avatar
    Join Date
    Nov 2001
    Location
    Melbourne
    Posts
    1,640
    When you say that the "gas' is clear, do you mean that it is invisible (detected by feel rather than sight) or merely that it lacks odour etc?

    Is the pressure limited to the rocker cover or do you also get fumes from the dip stick tube?

    If the latter, I'd be suspecting blow by from worn rings / liners, or possibly valve stems (though the latter is usually accompanied by visible fumes on decelleration to idle.

    If not, then its probably the emission control gear itself. I'm not familiar with the GTI "plumbing", but on an sLi I'd be looking at the feedback tubes to the injection system.

    Cheers

    Rod
    Rod's Home Page

    Rod's car page

    Peugeot 4008 2016Peugeot 407 SV HDi estate 2008, Peugeot 407 SV Hdi Sedan 2006, (deadish), - Previously 403s, 404, 504, 505 sLI Wagons, 406 ST 1997, 307 XSE, 306 XSi, Renault 12, Citroen DSpecial

  3. #3
    Fellow Frogger!
    Join Date
    Aug 2001
    Location
    Tamworth
    Posts
    150
    Thanks Rod,

    The air is certainly not visible, and I haven't had sniff of it yet - will try that. The compressions are 150-155 lbs. The real mystery is the tube that connect the sump to the rocker is clear (no obstructions or PCV ) but when you lift this tube off the rocker, you can feel a slight vacuum on the sump side, which indicates there is zero blow-by.

    Anyway, my mate Kim has just rebuilt his GTi and his engine does exactly the same. So we have come to the conclusion that it must be normal.

    However, we are still curious where it comes from.

    Cheers,
    Cheers,
    Brodie

    '78 604 SL (LPG) ...........for sale ..sold
    '81 604 SL (spares) .......for sale ..sold
    '85 505 GTi ..................for sale ..sold
    '94 405 SRDT............... for sale ..sold
    '07 307 HDi hatch
    '07 307 HDi Wagon

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
  •