hi, my vectra suffers from brief engine run-on and ticking/tapping sound. these symptons disappear if i force the ecu into limp/ safe mode (by disconnecting the cam sensor). the eml is throwing up a cam sensor fault. ive changed this but eml remains. (ive come to understand that the eml showing a faulty cam sensor is a bit of a red herring.) this all happened after i changed the cambelt, tensioners, rollers, water pump.
the timing marks are lined up so im sure im not a tooth out and ive tried the tensioner at 4 or 5 different tensions but no change.
my only train of thought so far is that the timing is advanced which is causing pinking (the ticking sound, although ive never heard a car pink before) and being advanced this may cause the engine run on. when it goes into safe mode, the ignition is retarded and brings it back into range. plus if the timing is out of range perhaps this is why the cam sensor is throwing up a fault.
incidentally, if i put my foot on the brake when i turn the engine off i get no run on.
my tiny lack of car knowledge ends there im afraid :)
thanks, kris
Edited by Pugugly on 22/03/2009 at 23:34
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your diagnosis sounds about spot on, however are you setting the tension the correct side, by this i mean are you turning the tensioner in the correct direction, it should be turned anti clockwise till the pointer lines up, engine stone cold, preffably left over night then checked, if you tension it the other way then the slack will be on the other side causing timming to be out giving you the symptoms, the only other thing that catches people out is some times the woodruff in the bottom sprocket gets chewed out so when you set it up it looks spot on but infact it can be out ,proof in the pudding is was the fault there before you changed the belt, if not then check and reckeck, also make sure that there is no free play in the water pump seen many belts changed then three weeks/months the water pump collapses (ouch) in fact got one towed in this week for same fault we told customer that it needed changing but she said cant afford it, she deff can't afford it now, new engine requried, regards TB
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hi, yes i adjust it anticlockwise. what do you mean by woodruff in the bottom sprocket? the waterpump is new and is in there nice and tight.
it was fine before i did the cambelt. ive spent countless hours checking and readjusting, im not sure what im missing! :(
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the bottom sproket (the bit that turns the belt) is located into the crank with a woodruff key but i assume that you have not undone the bolt in the middle (no need to you undo the four bolts) if you have then carefull look at the drive /woodruff assuming that you have not removed the cam sprockets (have you) are they fitted correctly they have two holes for the camshaft pins (if you have not removed them then you wont know what i am talking about) easy to put them wrong (but i would assume that it would not run ((valve dammage)) other than that i cant see what you have done wrong, they are virtually idiot proof, crank at tdc (mark on pully, mark in oil pump , both camsprockets at twelve o clock, swap tensioner, pump and iddler pullys, pump in correct position, belt on, tensioner anticlock wise till pointer in correct position (should end up pointing to five oclock ish, not the pointer but the bit that you put the allen key into) job done !!!!!
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hi tb, correct, i havent removed the bottom sprocket (crankshaft sprocket?). i can see the crankshaft sprocket also has a key on it that matches up with a notch on the inner cambelt cover so pretty sure its correct.
what you say about the 5 oclock position has me thinking....
with the tensioner, when i tighten it to its tightest point the allen key bit is at 2 oclock. i do two complete revs. i then turn it anticlockwise a tiny bit to release the tension and line up the marker with the groove, the allen key bit ends up at around 12 oclock. are you saying i need to rotate it anticlockwise past 12 oclock to fully release the tension then keep going anticlockwise until i get to around 5 oclock and the tension is taken up again?
one thing ive been wondering for a while... is it possible to manually retard the ignition by running a different tension on the belt? if so, would a looser or tighter belt retard the ignition?
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the pointer should be in the correct position with the allen key hole at about five oclock if not then the water pump is not in the correct position (ie it needs lossening and rotating untill the pointer is correct) the timing as such is not dependent on the tension of the belt because the sensor is in a fixed position in the block and so is its reference point (all be it rotateing in the crank), incorrect tension will make it run a little rough but you would hardly notice, the tension is more to stop the belt snatching as it rotates,Regards TB
Edited by topbloke on 21/03/2009 at 08:36
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ok, the haynes manual (ahem) says i need to tension it fully, turn engine, then adjust tension. should i do this or just go for the five o clock position?
im pretty sure the water pump is ok. it has a notch on it that lines up with a notch on the inner cambelt cover.
to be honest, ive tried enough by the book methods, im tempted to sit the tensioner at five oclock and rotate the water pump to take up the slack. this a good idea?
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From some of your comments i really suggest you just take it to a garage. Your first post seemed you were very clued up but some of the others are silly. i really dont mean that in a nasty way. If you keep tentioning your belt wrongy your going to fracture it intrernaly and it wont last very long. Your timing HAS to be wrong. The fact the belt could be loose enough to adjust the timing isnt your real problem. If it really is that loose i cant imagine once you rev it it ill stay timed. (timing slip). Even this was loose i still cant see that you could be advanced enough to make any difference. The electronic ignition would adjust this minute amount.
hope this has helped without insult. dan
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damn forum timed out and lost all my post!!
anyway, basic premise was:
-o- no insult taken;
-o- didnt run for long at wrong tension (less than a minute each tension) and never loose enough to promote timing slip;
-o- problem is a year old and belt is currently tight and looks good as new;
-o- two lots of insurance deposit, tax and mots between march and may thus cannot pocket what could turn out to be an expensive diagnosis without a possible resolution at the end;
thanks :)
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I dont think its to do with the belt tightnes at all. I think the timing is either out or you have created a problem electronically. Camshaft sensor ETC.
The engine has electronic means to stop engine run on. You need to get it onto an engine diagnostics machine.
The fact you mention if you press the brake it doesnt happen is pointing electronically. Is your car manual or automatic.
Also were are you in the UK.
I know you mention money but sometimes some things are better done by others. I am a mechanic and i dont like repairing my own cars.
Does the car start easily and rev ok. any misfire etc. all your answers help paint a better picture.
dan
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my garage is w*********************** just so you know im not just a bafoon. dan
lastly the tinking noise could quiet easily be the valves tapping the pistons giving signs of engine timing beeing out.
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my garage is.....
As mentioned in one of your other posts, if you wish to advertise, then please go about it in the correct way: -
www.honestjohn.co.uk/advertise/ads.htm
DD. BR Moderator.
Edited by Dynamic Dave on 22/03/2009 at 23:34
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car is manual. engine starts and revs fine, you wouldnt know there was a problem with it. if i accelerate hard you sometimes get flat spots, but these are almost unnoticeable and only if i put my foot down, and only sometimes. a symptom of the timing being slightly out no doubt.
edit: i'm in hampshire
Edited by kpm197 on 23/03/2009 at 12:20
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i adjusted the tensioner on friday and after driving it today ive noticed the ticking sound is much quieter. ill monitor it over a couple of weeks. if the sound changes more than once ill know its a sensor. if the sound stays like it is now ill know the timing just needs setting up.
will a mobile mechanic with a krypton be a good way to go for diagnostics?
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hi kpm, im a fellow vectra driver, in my experience metallic ticking, tappets type noises were related to engine oil. even if dipstick says 3/4 full the noises were present, but disappeared once fully topped up.
also i can remember that the wiring for the camshaft sensor is exposed to a greater chance of damage because of how its routed. i only remember because i recall breaking something to do with it (:)). have you checked for continuity/condition along the wiring?
hth
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hi, thought i'd bring this back up.
i removed the cam sensor pins from the ecu so i could test the resistance while running the engine and i got good cam sensor readings at the pins and no inteference. it must be something else fooling the ecu into thinking the cam sensor is duff.
i also adjusted the tension and rotated the water pump a little and the engine run on has gone (touch wood). it seems to pull a bit smoother through the rev range. i feels a little underpowered but i wont be touching it again. it can wait til i can get it on a diagnostic machine.
Edited by kpm197 on 13/04/2009 at 20:59
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