Can an airlock cause over-revving?

1. Ben_SaxoForte Saxperience Forum Bum Joined: Mar 2009 Stoke-on-trent Posts: 2640 Mk5 Golf GTTDI Mk2 VTR Project

   #1 17th December 2011, 17:27

   I was wondering can an air lock in the coolant cause the engine to over rev as in the revs not dropping how they should? the reason i ask is because ive had this problem for ages and ive tried allsorts, theres not a sensor i haven't renewed and the icv is a new original quality one.
   
   I also have a slight blow on the exhaust at the manifold, could this cause it aswell? I was thinking maybe if its blowing at the manifold the lambda could get a faulty reading and over fuel or something?
   
   Thanks
2. BertieG Established Member Joined: Oct 2009 exeter, devon Posts: 1224 Clio 172

   #2 17th December 2011, 17:44

   air lock will make no difference to the revs, will just cause it to overheat
   
   (my car does the same thing, id be interested to know if anyone has an answer!)
3. Ben_SaxoForte Saxperience Forum Bum Joined: Mar 2009 Stoke-on-trent Posts: 2640 Mk5 Golf GTTDI Mk2 VTR Project

   #3 17th December 2011, 17:49

   I was just thinking maybe it could give the temp sensor dodgy readings but im just running out of things it could be now and don't really wana go and buy a new manifold if its not gonna be that either lol. I've been reading on the net that an engine speed sensor could cause it aswell? not sure on that though as I thought that would probably mess up the speed rather than revs.
4. BertieG Established Member Joined: Oct 2009 exeter, devon Posts: 1224 Clio 172

   #4 17th December 2011, 17:58

   http://www.306gti6.com/forum/showthread.php?id=136023
5. vtrmann Frequent Poster Joined: Dec 2009 E yorkshire Posts: 947 53 black vtr

   #5 17th December 2011, 18:27

   Quote:

   Originally Posted by Ben_SaxoForte I was wondering can an air lock in the coolant cause the engine to over rev as in the revs not dropping how they should? the reason i ask is because ive had this problem for ages and ive tried allsorts, theres not a sensor i haven't renewed and the icv is a new original quality one. I also have a slight blow on the exhaust at the manifold, could this cause it aswell? I was thinking maybe if its blowing at the manifold the lambda could get a faulty reading and over fuel or something? Thanks

   mines still the same aswell mate, got another icv still same. sent it back and got one from scrappy today for a tener, fittin it tommorrow bit hung over today lol. ive done the same as you changed everything. so whatever the problem is with yours is probably the same as mine. my front pipe is blowing a bit aswell, i wondered if it was givin other sensors dodgy readings. i will let ya know what sorts it if ever does. its gettin a bit expensive now.
6. Ben_SaxoForte Saxperience Forum Bum Joined: Mar 2009 Stoke-on-trent Posts: 2640 Mk5 Golf GTTDI Mk2 VTR Project

   #6 17th December 2011, 19:02

   Quote:

   Originally Posted by vtrmann mines still the same aswell mate, got another icv still same. sent it back and got one from scrappy today for a tener, fittin it tommorrow bit hung over today lol. ive done the same as you changed everything. so whatever the problem is with yours is probably the same as mine. my front pipe is blowing a bit aswell, i wondered if it was givin other sensors dodgy readings. i will let ya know what sorts it if ever does. its gettin a bit expensive now.

   Yeah i thought mine was sorted when i changed the icv like it is better but still not right, i'm thinking its the exhaust now but its expensive to go changing that then find out its not that either lol, I'll let you know if I get mine sorted too
7. vtrmann Frequent Poster Joined: Dec 2009 E yorkshire Posts: 947 53 black vtr

   #7 17th December 2011, 19:22

   Quote:

   Originally Posted by Ben_SaxoForte Yeah i thought mine was sorted when i changed the icv like it is better but still not right, i'm thinking its the exhaust now but its expensive to go changing that then find out its not that either lol, I'll let you know if I get mine sorted too

   cheers i even changed the fuel pump on mine. last week the revs were dropping really quick and stalling starting on its own. now their sat over 1k and not droppin quick. not sure if its my icv but it needs doin coz i was cleanin it and managed to pull the shaft thing out, prob why i can only hit 5k revs some days?. its really annoying me now.
8. user_20080 Saxperience Hardcore! Joined: Dec 2007 smurfland. Posts: 17346 Ex saxo owner.

   #8 17th December 2011, 22:10

   Coolant temperature sensor maybe faulty & giving the wrong reading to the ecu.
9. Ben_SaxoForte Saxperience Forum Bum Joined: Mar 2009 Stoke-on-trent Posts: 2640 Mk5 Golf GTTDI Mk2 VTR Project

   #9 17th December 2011, 22:57

   Quote:

   Originally Posted by stevo67 Coolant temperature sensor maybe faulty & giving the wrong reading to the ecu.

   would I get faulty readings if the coolant isnt touching the whole of the sensor at all times because i seem to remember when I replaced it the coolant didnt come streaming out it was just below the hole so I might try and bleed the system see if it helps