jonah 1 Posted October 29, 2003 I have a very strange problem with the coolant level sensor on my 1.6GTi. Twice now, when thrashing the car hard, the coolant level warning light has come on and stayed on, even though there was still plenty of coolant in the system. What had happened the first time, and I suspect again this time, was that the end cap had fallen off the sensor tube and the float had got stuck half in / half out of the tube. But for it to drop down to the bottom of the tube, the coolant level has to have dropped... which it hadn't either time. Also the end cap shouldn't just fall off, especially as I superglued it back on last time! What the hell is going on??? Any ideas welcome... Cheers, Jonah Share this post Link to post Share on other sites
Simes 248 2 Cars Posted October 29, 2003 Get another one from he scrappy, Share this post Link to post Share on other sites
Pugnut 9 1 Cars Posted October 29, 2003 if the sensor is ok and the wiring then there's chance it could be the headgasket. myself and someone else on this forum has experienced this (was it gaz or gav ?) anyway when giving it some the coolant light would flicker when the tank was full/sensor good/wiring ok. bubbles going into the header tank. my gasket was gone between a cylinder and the water . hence no water in the oil or vice versa . just started on 3 cylinders from cold occasionally and used a litre of water a week roughly . Share this post Link to post Share on other sites
jonah 1 Posted October 29, 2003 Hope it's not the head gasket... have half suspected it for quite a while. But, I've had a sniffer test done (to detect exhaust gases in the coolant), which didn't detect anything wrong at all, and it doesn't use any water under normal use. Is it possible that the h/g is only blowing under "extreme" conditions? Share this post Link to post Share on other sites
Guest justin85 Posted October 29, 2003 Hmm. I have a 92 1.9 and sometimes (especially on inclines) on full throttle the light comes on - goes off as soon as I close the throttle and seems to flicker with as the revs rise and fall. Only happens occasionally. Car doesn't use any coolant at all. Hmm. Intriguing. I love these little problems. Justin. Share this post Link to post Share on other sites
Guest richt Posted October 29, 2003 My old 309 used to do this, removed the sensor and cleaned it up with some emery paper and it was fine. Share this post Link to post Share on other sites
205man 0 Posted October 29, 2003 take the sensor out and clean it, as they are porn to getting crap in them, especially if the coolant not changed recently, maybe worth flushing the system through to het rid of any more muck that maybe in there to stop it again. if it doesnt solve it then get replacement sensor before worrying about head gasket, but if it not using water then doubtful its the gasket gone alan Share this post Link to post Share on other sites
jonah 1 Posted October 30, 2003 Cheers for the suggestions guys. I've already cleaned out the sensor, coolant has been changed several times recently for various reasons so I'm happy there's no sludge in there. What I'm trying to get at is not what's wrong with the sensor, but what's wrong with the rest of the cooling system that makes the float fall out of the bottom of the sensor. One thought I had was that a sudden collapse in pressure in the header tank would make the air in the sensor tube force everything out of the bottom - that would explain the problem. But i can't figure out what could cause a sudden pressure drop... Anyone? btw Richt - apparently the sensor on the 309 is completely different from the 205. I guess you're talking about the one with 2 metal prongs? Share this post Link to post Share on other sites
Guest richt Posted October 30, 2003 yeah sorry both my Gtis have been 92Ks, didnt relise the early cars had a differnt one. Both mine have had the black plastic expansion tanks. Share this post Link to post Share on other sites
Guest sibbers Posted January 19, 2006 I've got a problem with my coolant level, either dropping or the sensor being funny. My 205 is a 1.9 on a D plate (old!) I filled it to the brim when I saw the light come on a couple of days ago (only owned it for a week) and its came on again today - checked the level and its down by about 3 or 4" but I would expect it to have chucked some water away having filled it so high up. How high should the water level be before the dash light comes on? Also, what could it be if not the HG (as I have no other indications of HG fail) Share this post Link to post Share on other sites
jonah 1 Posted January 19, 2006 Very old thread to resurrect! Maybe it's about time I updated it with what I found the problem was anyway! In my case it turned out to be the head gasket after all. It was only blowing under full throttle conditions when it would let combustion gases into the cooling system, pressurising it suddenly which caused the pressure cap to vent and spew out loads of coolant. The mass of froth in the header tank was fooling the sensor and bringing the warning light on. In your case... the correct coolant level should be about 2 inches below the top of the tank, so if it has dropped much more than that then yes the warning light would start to come on. (count yourself lucky that the sensor still works at all!) Don't brim it as it could overpressurise the system and burst hoses / water pump seals. If it is losing water and there's no visible leak from outside then check the carpets in the front footwells... if they are wet then the heater matrix could be leaking. If not then sorry but it's most likely the head gasket... Share this post Link to post Share on other sites
Guest sibbers Posted January 19, 2006 i think it might be, I've just taken the thing to pieces and found some bits of mayo. Its only got 74k on it - i guess cold short distances has been its way of life previous to me. I was looking for the oil filler cap (and I have no idea where ti is) and have removed a large plastic thing with hoses going into it (two large ones at the bottom, two smaller ones at teh top with one going to the throttle body) - is this the SAD device? I'm going to go and refit it and top up the water again, its odd - it appears to have used the water but I don't see any exhaust signs (and the mayo I've seen so far could easily not be HG as it hasn't done many miles). Share this post Link to post Share on other sites
James_m 0 Posted January 19, 2006 My coolant light was on pretty much the whole time at a trackday on sunday with no real noticeable loss of coolant. im worried now.... Share this post Link to post Share on other sites
Guest sibbers Posted January 19, 2006 my coolant level seems to be at the two inch area. hmmm. carpets arent wet btw Share this post Link to post Share on other sites
stutto 0 Posted February 9, 2006 Bit of a hi-jack - sorry. Does anyone know where I can get a new coolant level sensor for less than the £22.04 plus VAT that my local Peugeot dealer wants? I have tried GSF and ECP and neither seems to stock them anymore. Thanks. Share this post Link to post Share on other sites
pug_ham 242 3 Cars Posted February 9, 2006 I was looking for the oil filler cap (and I have no idea where ti is) Before you do anything I suggest you familiarise yorself with the Engine layout to save causing lots of problems by putting the water into the wrong place. You don't want to mix water in the sump & kill your engine. That link doesn't show the SAD but there is another page on the main site that explains the SAD thoroughly. It is usually underneath the distributor & has just two hoses for it. One from the bottom of the inlet manifold & another that leads back to the intake system hose between the AFM & throttle body. See the picture below for one (off the car & minus the hoses) but it'll give you an idea of what you're looking for. From your description I haven't a clue what you were looking at but this could be the oil filler cap. Does anyone know where I can get a new coolant level sensor for less than the £22.04 plus VAT that my local Peugeot dealer wants? I have tried GSF and ECP and neither seems to stock them anymore. You've already tried the usual two places outside of Peugeot but you could also try Autofive, peugeotparts.co.uk or Neat Autos. Graham. Share this post Link to post Share on other sites
stutto 0 Posted February 9, 2006 Eeek! Went to the dealer and found out that my car has a phase 2 header and therefore the sensor is £34 something, presumably plus VAT. Plus they did not have one in stock. Share this post Link to post Share on other sites
pug_ham 242 3 Cars Posted February 9, 2006 IMO the phase 2 tanks & sensors are worse then the phase 1 ones. At least you can clean the phase 1 sensors to get them working again. Only time I've known a phase 2 one to work was when it was suffering from interference due to HT leads routing. Graham. Share this post Link to post Share on other sites
jonah 1 Posted February 9, 2006 Yep the early type sensor can usually be repaired, either they clog up with silt and just need washing out, or the reed switch casing can crack if a bit of moisture gets in. New reed switch = 50p from Maplin Share this post Link to post Share on other sites
Rally Slag 0 Posted February 10, 2006 on my D reg 1.9 gti the little light next to the collant temperature is allways on, has bin on since i bought the car and sometimes for no reason the over heating light (asume its the overheating light, just below the battery light in the centre of the dash) comes on, i was sitting there once with the engine turned off and just ignition on and that light came on lol so somethings giving a wrong reading. What is the light next to the coolant temp gauge for? Also why would it be on, my temp gauge dont work properly either I dont think, sits at 1/4 of the way when ignition off and half way when ignition on or engine running and doesent ever move, it runs fine, dont loose any oil or water and all oil and water is nice and clean. Oil temp gauge packed up completly the other day aswell lol Share this post Link to post Share on other sites
Guest BrainFluid Posted February 11, 2006 I would'nt advise anyone to fill there tank up to the brim on an older motor. If you have a weak pipe, the extra pressure that it causes in the coolant system which pushes the excess coolant out, can break. Thats what happened to me anyway, sure it would have happened at somepoint anyway but it was a hell of a time for it to happen (on the bloomin motorway) Share this post Link to post Share on other sites
pug_ham 242 3 Cars Posted February 12, 2006 on my D reg 1.9 gti the little light next to the collant temperature is allways on, has bin on since i bought the car and sometimes for no reason the over heating light (asume its the overheating light, just below the battery light in the centre of the dash) comes on, i was sitting there once with the engine turned off and just ignition on and that light came on lol so somethings giving a wrong reading. What is the light next to the coolant temp gauge for? Also why would it be on, my temp gauge dont work properly either I dont think, sits at 1/4 of the way when ignition off and half way when ignition on or engine running and doesent ever move, it runs fine, dont loose any oil or water and all oil and water is nice and clean. Oil temp gauge packed up completly the other day aswell lolI'd suspect a wiring fault, definately for the oil temp sensor. The wire breaks off as it is fairly susceptable to getting brittle due to its path to the sensor in the back of the sump. The little red light next to the water temp guage should go out instantly when the engine is started so if the wiring checks out OK then that might be a sensor, afaik it is controlled by the smaller sensor of the two at the back of the thermostat housing, maybe this is another wire that has broken off doe to old wiring. AFAIK your car won't have the brown multiplug that can sometimes be the cause of annoying little problems such as these & the wiring runs direc tly from the fusebox. Graham. Share this post Link to post Share on other sites
Rally Slag 0 Posted February 13, 2006 cheers dude, had it on the ramp at work on sat, the wire is still on the sensor on the sump and looks intact the hole way up, mayby a new sensor is in order, i cant quiet remember what happend i was playing arond with the tuning and left it running for about half an hour to warm up, im pretty sure it was working at the start of the half hour but when i came back it wasnt working, and yeah i think there sender units for the water stuff ave just packed up, im pretty sure there wires are all there still, only thing i cant work out is why would the water temp gauge not return properly to cold like the oil temp, it allways just site at 1/4 of the way when ignition off then half way when ignition on, there the only 2 positions it goes to, what about the red light next to the oil gauge, should that come on when you turn the ignition on and go out when you start the engine, because it never comes on, think there is another sensor for it somewhere thats not working aswell Share this post Link to post Share on other sites
stutto 0 Posted February 16, 2006 Incase anyone is interested, the new sensor seems (crosses fingers etc) to have cured my flickering light. When I took the old sensor out, one of the prongs seemed to have attracted all of the sediment from in the system and was like a lollipop. When I tried to scrape it off, the top of the prong went with it. I tried to remember my schooling and I am sure that it will be something to do with one prong being an anode and the other a cathode but I can't remember which or exactly why it happened. Share this post Link to post Share on other sites
Rally Slag 0 Posted February 17, 2006 i tried aking mine appart and when the end came of it fell on the floor so i lost some bits i fink so now it dont work at all, well im pretty sure it dont work lol get a new one when i got money Share this post Link to post Share on other sites
