erratic idle

[saucy_begger]

yep im back again

my car was running perfect for a couple of days and so smooth, then..... all hell broke loose

this car is crazy and worse than ever. i came home from work a couple of days later after the car was fixed or so i though. i pulled up and noticed the smoothness was gone and the car had a slight shake then smooth then shake and so on. everyday its got worse so now it shakes like crazy and misfires every 2 seconds. ive not had the eml flash up once.

ive took off and checked the map sensor and hose again and its fine everything is how it should be. the strange thing is ill drive it a wile then pull up to lights and hay presto smooth then ill drive a wile and stop and its back shaking again? what is going on. the car is bucking when i give it some gas in any gear. ill take my foot off the accelerator then every time i put it back on the car bucks till it gets back to speed.

2 of my ht leads are corroded and green. i fitted some cheap crap ht leads that were hanging about that are not much better than the 2 corroded leads i have on my engine. the 2 corroded leads are actually going to cylinders 1 and 4 not 1 and 2 like i thought before! anyway so i changed these 2 leads tonight and noticed the misfire is half as bad and the car isn't shaking anywhere near as bad and the bucking isn't anywhere near as bad and i also noticed the car is quite a lot quicker too. the shaking is on and off now but its getting worse the more its driven. it was never like this but since i fixed the map sensor its gone crazy.

my symptoms are...

from cold a slight misfire and slight shaking. as it gets hot the symptoms get worse but if taken for a run and left to idle its on and off with the miss and shaking.

its going in for a new distribution cap and leads that actually fit the cap and new plugs. i was gonna get the coil changed too if its cheap enough.

am i heading in the right direction cos ive about had enough of this engine.

[planetc]

I would think that it will be a lot better once you have sorted those leads, judging by what you have described.

[saucy_begger]

thanks paul i hope its the leads or one of the electrical system parts im changing because its costing me alot of money now and im getting fed up. the car was perfect but it seems its one thing after another with this engine.

[planetc]

not necessarily the engine, more the bits that are attached to it

[Robsey]

Hmm - I would agree with getting the leads changed.
That green corrosion blocks the passage of the eletricity that you need to operate your spark plugs.

[Ritchie]

Check the temp sensor is cliped in rite

[saucy_begger]

ill start from the top

well i had a bad idle before all this for years but had me head gasket replaced recently as some of you know. i thought that would fix the idle as i had a blown head gasket but it didn't. so i got to work researching about my engine. after checking everything i found my map sensor hose was split and hanging off so i cut both ends back to good rubber and refitted and it was perfect and very smooth.

after a few days it got really rough not low idle like before but misfiring a lot and the steering wheel is shaking on and off quite bad. i took the leads off at me sisters and cylinder 1 and 4 leads are dark blacky brown and covered in greenish white stuff. the rest are perfect and shiny gold. these 2 leads don't fit right and will fall out if wobbled. if the connection the leads touch in the dizzy are at the top of the dizzy cap inside then my leads are not touching it because the plastic sleeve around the copper ends are limiting how far they go in and they are the only thing holding the leads into the dizzy. i got a couple of screws and screwed them into the copper ends so they are closer to the top inside the cap and i turned the engine over and it struck up strait away quicker than normal but had a strange miss like just 1 instead of 2 like a bob, bob, bob every second not like before it was a bob bob, bob bob, every 2 seconds. i pulled the leads and removed the screws but snapped the copper end off one so had to use some cheap leads i bought off ebay. i replaced both leads with these dark corroded leads cos thats all i had but on test run noticed the car isn't shaking anywhere near as bad and also had a lot more power and is quicker. still a misfire and shaking on and off but not as bad.

i can drive the car but it is hesitant/bucking on acceleration, sometimes bad some times not so bad. and sometimes i can stop at lights and it shakes like mad with misfire but ten minutes later ill stop at more lights and its smooth again but not 100%

i think and correct me if im wrong but i think ive always had this problem but its been clouded over by the vacuum leak and because it was the map sensor hose it wasn't reading right/low air so was giving me a rich mixture so in turn misfiring less because of the over fueling but now ive fixed the map hose its giving me the correct fuel amount meaning less fuel so its making it misfire more?

[saucy_begger]

hi guys, i know no one wants to talk to me cos i do go on quite a bit and im sorry about that but i now know why my car misfires...

the garage fitted my engine with bosch ht leads but fitted a lucos dizzy cap. (bosch lookalike)

the lucos dizzy cap doesn't have center pins that the bosch ht leads are designed to click onto so my ht leads are just pushed in there and basically not connected to anything and are working by arcing with no physical contact this really does explain a lot like why my leads randomly fall out the cap and i have a misfire and erratic idle on and off.

[saucy_begger]

i cant actually find a bosch dizzy cap for my engine c18nz? i can find cheap ones but i need the bosch one because of the center pins.

does anyone know where to get one please.

[planetc]

i cant actually find a bosch dizzy cap for my engine c18nz? i can find cheap ones but i need the bosch one because of the center pins.

does anyone know where to get one please.

Lucas caps are crap, they arc at the back of the king lead terminal, I've said this before. It's years since I had to source one but the bosch cap was one of those never forget part numbers, assuming it's still the same number.... 90442358.
Have patience dude, bear in mind we have lives aside of the forum and feedback can't always be straight away.

[saucy_begger]

thanks paul, oh i know but i do go on

yeah you did mention this to me but ive been to the old mans tonight tinkering thats how we found the cap was lucas and had no center pins :s

me dad said strait away this cap has no center pins to hold the leads i was like aahhh thats the problem.

nice to see the garages we use do first class work on our cars

thanks again, neal.

[saucy_begger]

hi guys,

well shes back in the garage! ive got a list of things im having done tomor morning oh well here goes

rotor arm
distribution cap
ht leads
spark plugs
clutch kit
oil return pipe gasket
oil change
thermostat

my thermostat is stuck open n not letting the engine heat up. the heaters are warm but obviously not hot :s

slight misfire and shaking car but as i mentioned my leads dont fit in the dizzy cap properly and work by arking :s

oil looks a bit dark and is old now so thats being done anyway.

plugs are old anyway so ah they getting changed

my dizzy cap is lucas... enough said

my clutch is fooked im finding it bit hard to get into gear lately n have to double clutch it to change smoothly sometimes and clutch getting worse with tough to press down and noisy lately like a whine

[saucy_begger]

good news everyone!!

prof-farnsworth.jpg (7.6 KiB) Viewed 692 times

£900 later and finally my cav is running perfect

well it only took a

head skim and head gasket kit
rocker gasket
cam belt kit
3 in 1 clutch kit
oil and filter change
distributor cap
rotor arm
h.t leads
anti roll bar links cos they were snapped
oil breather gasket
coolant temp switch
thermostat
coolant change

sure there is some other stuff but this is the stuf thats cost £900

it was in the garage for a week all in all just got it back today and she is running perfect clutch is crazy light as if its just a peddle on a spring and she is quick. i would say almost twice as quick on take off.

steering is a lot more responsive and idle is great. i have a slight bop every now n then from the exhaust but the garage said its not a misfire it just idles slightly rough because its a 8valve with single point injection.

i think she drives better than ever and feels so smooth and quiet and great to drive with the new clutch, effortless drive now. ive spent a lot getting her up to standard but she is the best looking rust free cav i have ever seen, in fact I've never seen one without rust.