1.8 16v misfire - rocker cover gasket, dizzy, leads?

[ben16v 0]

hey, could an engine misfire be earth related?

 

at low revs under load my car misfires and pops in the exhaust, plugs, leads, rotor arm, dizzy cap all newish, new tank of fuel put in there and had mixture checked

only asking if earth related is possible as i noticed tonight that the rev needle and speedo needle jumped when it misfired - if so where to check for broken earth and what to repair it with!?

 

cheers

 

ben

[ben16v 0]

bump

 

or am i totally on the wrong path

[n3p 3]

I'm not sure about an earth connection, but you said the leads, dizzy are newish - I know it sounds silly but have you checked them? I only ask because I had similar symptoms on mine, and it turned out to be oil filling up a cylinder and fouling a spark plug (new gaskets sorted it). Could be a number of things tho - checked the hoses for any leaks? cleaned dizzy cap? I read somewhere that the distributor hall sender could affect it? not that familiar with it tho..

 

Also is your car kept locked up overnight? Once had a problem with damp causing my car to misfire, left it on the driveway the next night and the problem cleared! If only it was always that easy eh

[davidwort 0]

hey, could an engine misfire be earth related?

 

at low revs under load my car misfires and pops in the exhaust, plugs, leads, rotor arm, dizzy cap all newish, new tank of fuel put in there and had mixture checked

only asking if earth related is possible as i noticed tonight that the rev needle and speedo needle jumped when it misfired - if so where to check for broken earth and what to repair it with!?

 

cheers

 

ben

 

wouldn't have thought it's an earth but it would be a good idea to check the straps anyway on the age of car, you should have one from the head to the coil mounting bracket and the big one for the starter direct to the battery -ve

 

I'd check your plugs again, see how clean they all are, will help to see whether it's related to one cylinder or all and so whether it's one plug/lead or before the distributor in the ignition system, check the dizzy/cap inside to make sure there's no arcing or oil from the seal to the head in there

electrical stuff tends to break down under heaviest load as that's the point at which weaknesses like high resistances show themselves in electrics, so it sounds less likely it's fuel related, coils are usually pretty reliable

the hall sender might be playing up, but generally they just die, give no signal to the ECU and so you get no spark at all.

One other thought, at low revs under high load the inlet vacuum is highest, might be worth checking the vacuum hose to the ECU from the manifold.

[ben16v 0]

thought about damp so have been liberal with the WD40 in an attempt to cure it, doesnt seem to make a difference, car is kept outside at night, the misfire is intermittant so i did think vac lines but couldnt see any cracks,

 

if i pull my plugs out what do i look for?

 

cheers

[ben16v 0]

just whipped plugs out all ends are the same but the thread on 4 (closest to dizzy) was a bit oily, could this be running down and fouling plug? what the cure for that new rocker cover gasket?

[n3p 3]

just whipped plugs out all ends are the same but the thread on 4 (closest to dizzy) was a bit oily, could this be running down and fouling plug? what the cure for that new rocker cover gasket?

 

Yeah, rocker gasket. Providign the plug is "ok", you could clean the plug and cylinder and give the car a spin to see if it drives ok for a little bit. If it does but soon starts to misfire, then thats probably it.

[ben16v 0]

just whipped plugs out all ends are the same but the thread on 4 (closest to dizzy) was a bit oily, could this be running down and fouling plug? what the cure for that new rocker cover gasket?

 

Yeah, rocker gasket. Providign the plug is "ok", you could clean the plug and cylinder and give the car a spin to see if it drives ok for a little bit. If it does but soon starts to misfire, then thats probably it.

 

thats exactly what it did, drove for 7miles then turned it off when i started it again the misfire came back gradually getting worse.

 

should i get it from VW? how much?

 

cheers

 

ben

[n3p 3]

You could get VAG quality Elring branded cam cover gaskets from GSF, shouldnt cost no more than £15-20. :D Good luck with getting it sorted mate

[davidwort 0]

Don't bother with a VAG cam cover gasket if they're more expensive than elsewhere, I've tried GSF and a FEBI one from AVS, as well as a new VAG one, no difference in them, they're all prone to leaking at the arcs over the ends of the exhaust cam, doesn't seem to make any difference whether I clean the mating surfaces really well or even put blobs of sealant in the corners, i think they're just a rubbish design.

The last one I bought was under a tenner, so don't pay much for one.

Unless the plug electrodes are really fouled, I wouldn't have thought it's that causing your problem though.

[steveo29 0]

if its still popping and banging , id consider the hall sender

 

mine did the same and another dizzy fixed it

[ben16v 0]

right been to garage, strobe light was all over the place, gonna whack a new dizzy on

 

cheers

ben

[ben16v 0]

put new dizzy on

misfire still there :censored: anyone got a set of leads for me to borrow or buy

 

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