Hi i have a p reg cinq. was driving to work and suddenly saw loads of white smoke out the back and it started to miss again. it missed before on number 2 but took plug out and saw was coated in oil. cleaned and put back ran great. headgasket or maybe something more fatal??? may take off head to look. please help!!!!!!!!!!!!!

White smoke sounds like a possible headgasket failure.

white smoke probably steam and, if the engine has warmed up the only likely cause is head gasket failure. a compression test will reveal all.

oil and water in the cylinder? sounds like an HG.. pressure test time

lots of oil every where but think thats cam gasket. if i take the head off you reckon that may show the problem? wot kind of job is it? cam belt?

have had compression tested and they said had no compression on no2. maybe dropped a valve?

sounds like a valve to me too,if u take the rocker cover off and check the valve springs u will probley see one poped off if the pistons hit it hard and broke the valve off and u would hear it rattling in the chamber, but if u kept driving it will be inbedded into the top off the piston,the oily plug u had was probley the valve bent but steel in place,wip the head off, if the scoring isnt to bad ie not deep just give it a bit of a rub down to take the rough off replace the valve and give it a try, ive done these before and the car still going strong and it happened 2 years go

Have taken the head off. Pistons look fine, head and valves all look fine.

Running out of ideas. Any one got any ideas???:bang:

What about the gasket? Look for holes around the burn ring on no 2 cylinder.

The gasket looks ok its not broken any where.

There doesn't seem to be anything that stands out to be wrong.

You'll need to get the head pressure checked and skimmed.

Cheers

D

The head has now been skimmed and crack tested, all ok. Its had new spark plugs. The HT leads are fine and the the oil valve stem seals are ok.

Head is now back on. Engine runs but there is still a mis fire and oil is still being burnt. But I dont have any idea what it could be.

Please help?????

Back to basics. With the engine running using insulated pliers remove one plug lead at a time, replacing it before removing the next one.

You should get one where the removal of the lead makes no difference to the misfire. That should be the cylinder with the problem.

Compression test, and, if as suspected is low, add oil. If the compression comes up, it will be rings or bores.

Cheers

D

Have checked for spark. all there, but on no3 no spark out of end of lead. when tryed to see if had spark, saw spark out of coil end!! what does this mean?? then did copression test and found practically no compression on no2,the other 3 had v high pressure. as had head skimmed and crack tested, and valves cleaned and reground could this mean bottom end dead?? am gettin v stressed and frustrated. help!!!:bang: :bang:

Do what rallycinq suggested, compression test each cylinder dry, if one is low put a bit of oil down the bore.

If the rings are toast the oil will temporarily up the compression as it stops leakage past the piston. Throttle wide open whilst you test wil give you the most consistent result. There should be no more than a 10% variation between the cylinders.

ok cool then that should show the fault? why was the no3 plug lead sparking at the coil end??

Yes it should. An engine needs 3 basics to work, fuel, compression and ignition. Obviously if your ignition is sparking someplace other than the sparkplug your engine won't run properly, it sounds like you have a failed ignition lead.

I reality though all that will cause a misfire, not clouds of smoke or low compression. Diagnose the bottom end, only once you're sure that is serviceable is it meaningfull to deal with the ignition issue.

swopped over plug lead and still sparked at the coil. nackerd coil? its starting to look like its going to need a new engine. dont wana strip head again. so if i put oil dwn the bore, and retest it do i fill it up then put tester in? flaming car!! why cant it be easly to sort out. wish it was something obviuos like a broken valve/piston.

You only need to put a little oil in, say something like a dessert spoon full. It need to coat the top of the piston and the rings to temporarily seal the piston. This won't last for long, but if the compression rises, then falls again it definately the rings or bores.

If the compression does not change then its the head, but you know thats alright.

If the spark is still happening at the coil, even with the complete lead swapped, then the coil has split. You will not get any spark at the plug because the spark will take the shortest route.

You can replace the coils individually, so you only need one, although changing one often causes the other to go.

Cheers

D

do they? ok thanks mate you have been v v helpful. hope aint been to annoying? will try wot u say some time this week. thanks again. will let you no how it go.:worship: :worship: :worship: :worship: :worship: