having a few probs with my cinq. well... just one actually. it not really a problem but its weird... anyway.. ill start at the beginning.

i drove to wales about 3 weeks ago to goto a party, anyway, on the way up there the car was jerking and loosing power when pulling off from lights but seemed ok once it was going... it just basicly had a really bad flatspot between 2000 and 3500rpm for no reason.

anyway... goto to wales and found the prob.. it was a split vacume hose... a bit of selotape later and the prob was gone... anyway... on the way back from wales the car seemed on but would occasionally jerk a bit when putting my foot down. whilst putting my foot down at one point, there was a large back (sounded like it was coming from the engine but i think it was a misfire) and the car jerked violently and then continued on as normal... i pulled over to check the car and noticed that the exhaust was making a nasty noise.. as if there was a hole in it...

I put the bang and the crappy noise down to that maybe a hole had blown in the zorst. anyway, after this i didnt have anymore misfires and the car drove perfect except for the nasty exhaust noise (very rattly and tinny) so, last weekend i got under the car and checked it out... no hole... but the centre pipe had become slightly detatched from the backbox so i pushed em back together and tightened the clip etc. anyway... the nasty zorst noise has gone now but the misiring has returned.. its not that violent but it is there... when accelerating it sometimes bangs and then jerks forward and then caries on as normal.

I think its a misfire anyway... sounds like it but it sounds like its coming from the engine and not the zorst so im a little worried.


so i dont know what to think it is... i recon its got something to do with the zorst system but i dont know what. but then again could it be something to do with the split hose (which is still selotaped tight and sealed).

any ideas?

Try this little test. Accelerate gently to say 5000 revs in 2nd, then lift off the throttle and let the engine slow the car. When the revs get to around 1800 - 2000 floor the throttle and see what happens.

I'd say you need to change that hose you sellotaped though, a vacuum leak can have some funny results.

yeah i agreei probably do need to replace the hose heh... its weird tho.. the engine runs even if u take the hose off completly heh

ah well.. ill try ur test tomorra,, see wat happens..

what should happen>?

If everything else on the engine is ok and you do that test, nothing should happen - it should just accelerate.
If it misfires a little then goes, chances are something more sinister could be happening such as a dodgy head gasket. When you let the engine brake the car like that, it creates a very high vacuum in the cylinders, so it will draw in oil / water etc. through a bad gasket.

Could equally be a MAP or Lambda problem, but the split hose I'd say may be the root of the trouble.

mine does this jerking buisiness sometimes and it is really annoying especially when doing about 60 down the d road adn you nearly get rear ended it is usually after the injor light has flashed on for about 10-15 seconds

ah well if replacing the hose doesnt make my probs go away and it turns out to be something like the head then im just gonna ditch the engine and go for a 1.2

there isnt any mayo in the cap tho... and the car isnt drinking coolant/oil... yet

might nip to halfrauds and see if i can get an equivelant hose

right... seem to have sorted the prob.. i went to halfrauds and bought a hose which i thought would be the right diameter (5.5 and it turned out it was too wide)... but i wasnt... anyway.. ive made up my own hose using the too wide halfrauds one and the old split one! worked a treat!!... anyway... took the car out for a drive and it was pulling alot nicer and smoother but after a while there was BANG... another misfire sounding thing so i came back home and had a look under the bonnet (cause it still sounded like the bang was from the engine adn not the zorst...

turns out that the little filter from my inmduction kit had fallen off and had wedged itself down where the timing belt and all that was!... it was basicly blocking the thing from turning smoothely and the filter had been grinded to pieces so i presume it was that falling into the turning thing and causing it to jam momentarily... kinda weird but atoleast its all sorted!

YAY

Lucky escape then Bush, could've ended up with a broken timing belt or similar.

How did you not notice the filter being missing?

Liam

just noticed that it wasnt there heh... nothing particular and then i was lookign to see where it went (thought it might have just fallen out and onto the road) and noticed it was wedged in between the bent and the side of the engine bay.

right... its just done it again so it wasnt the air filter jamed between the timing belt...


i think i might have done something a little more serious... it only misfires at low revs tho... and only when its at running temp... anyone anymore ideas? i still think it might be down to the zorst as the first time it happened it broke the zorst and then never misfired again.. now ive fixed the zorst its misfiring...

help

Hi, sounds like you have a blocked exhaust, possibly back box as you say the missfire happens at 2-3k revs and fine at idle and the car was fine when the exhaust was seperated. The filter you mentioned must therefore be the breather filter(aftermarket filter), this can get blown off if there is a back pressure build up in the engine caused by a blocked exhaust. Check to see if your oil consumtion has increased, this should confirm the exhaust theory..

I have the problems you described bushboy, but i have mayo in the cap and i am losing collant into the oil. When this first happened i thought it might be a spark plug but after a few days the "white stuff" started to appear in the oil and the collant started to go down, thus suggesting it was the head gasket.

Mine does misfire and dumps unburnt fuel into the zorst system and at that point the car backfires as the unburnt fuel burns off inside the zorst. This only happens when the car is has been sitting for a litttle while and from cold starts. I am 90% sure this is because when the car has been sitting the water has been getting into one combustion chamber (the one where the headgasket has gone) and prevents the spark to light the fuelair mixture in the chamber. But afer the car has warmed up a little bit the misfiring cylinder stops and works correctly, suggesting to me that the damp/water in the chamber has dried out.

I remember when it first went I thought there was a hole in the zorst as the zorst was making the same noise it did when my flexi pipe went. Also the rear end of the car smelt really bad as i could smell the fumes produced from burning the unburnt fuel in the zorst system.

Hopefully this will be all sorted tomora and wednesday with the help of brian.

HTH

David

Mine does that Bush, but I know that the compression is down, cos I reassembled the 1108cc head rather quickly and messily!

Could be the timing being a tooth out or the start of a head gasket death Id say!!

ive sorted the prob anyway.. a new set of leads and a new hose for the vacume thing did the job... dunno which fixed it tho.