vibrate/misfire

greenbeast

HI all i am new to this so bear with me (lol)i have recently replace my broken timing chain allong with new injectors and spark plugs and a coil pack but its still misfiring on cyl no 4 and the engine vibrates like hell until you get to 2500 revs then all is fine i just cant figure it out has anybody had probs with this too?
help would be appreciated HUGLEY :?

MikeS

compression test would be a good start

how do u know it is cylinder 4 ?

does the eml come on ?

greenbeast

yeah the eml light is on and 3 sparks have shown signs of firing but the fourth one is still brand new

MikeS

you need to get the engine management code 🙂

john2666

you say the chain broke?? if so i am guessing valve damage, £18 for a compression tester at Halfords will do the job, if you have had the valves done and still misfiring, check the injector seals, can you hear a hissing noise near to the injector where they enter the head ? failing that it is possible you could have bought a faulty coil pack. Where in the UK are you do we have a member near you with a tech 2 ? I am in Bury in Lancs if you are anywhere near

greenbeast

no thankfully it went for testing and cost me £50 it snaped when i turned the key to start it it sounds like i was one of the lucky ones so far
but i live in north wales and i have checked the injectors which are brand new ones but the coil pack does come with a 12month guarantee but i was also thinking that myself ,i was also thinking maybie the balance chain is naff??

john2666

Even brand new ones can be faulty i personally would check out the coil pack

MikeS

do a compression test as 2&4 cylinders are linked together concerning ignition

this engine has no idle control valve or cam sensor so it purely done on compression of cylinders for the spark

as for the eml showing no 4 cylinder failure then take out the coil pack and turn her over, can you see fuel haze coming from recess

you got a volt meter on the injector connector for that cylinder

for the spark to have no sort of discolouration then surely no fuel is entering that cylinder, the plug would stink of fuel if the injectors were working fine and the coil pack was faulty

i have seen the returns logs for my local vxhall dealer concerning coil packs booked out by technicians just to be brought back, something like 16 returns and only 3 were faulty

so though it seems a coil pack problem it is uncommon for them to break down on these engines

vocky

sounds like bent valves to me, get another compression test done, it should have at least 10psi per cylinder

john2666

Vocky's probably right, even though it went on turning over, mine went on tickover on the driveway and all 16 valves got it!!!

greenbeast

well gents i bought a compression tester myself and did the test myself i am getting 13bar on cyllinder no 1,2,4,but no 3 is giving me 8bar so it is all stripped down again and the exh valve is ever so slightly bent. i went back to the garage with the head and they cant beleive they missed it (wonder if it was tested now) so they are now going to put it right .(cowboys)