Vaxhuall Corsa D 1.6 T Sri Misfire HELP!

watercoolednoob

Hi guys i had bought a vaxhuall corsa about a month ago 2008 model with 48000. i immediately done a service replacing spark plugs,oil and oil filter and it ran perfectly for 3 weeks. one day on the way to work i had noticed a white smoke in rear view mirror i pulled over and checked everything i had a obd scanner hooked up and temps were ok and no DTCs because it was cold i continued driving and did not notice any more smoke. coolant was not low. there were no problems until 1 week ago where under hard acceleration i would notice a misfire it was not noticeable at idle or revving it with no load or under a high load at low rpm, only when high rpm(4k+) it would have a misfire, lack of power and a lot more burbles and pops. there was still no DTCs. next day i went to start it smoked a lot and pretty sure it smelled like coolant (although even today the coolant level has not dropped). finally i got some DTCs i had orignally misfire with low fuel but i had no fuel at the time so i filled up cleared DTCs and drove aggressively and got 2 DTCs one misfire detected cylinder 4 and just misfire detected. i have replaced coil pack that did not do anything. any advice on what this can be the oil is not milky and there is no smoke coming from coolant tank. it still sucks down on the dip stick. i have not done a compression test. any ideas or if any of you have had any experience with these engines please any advise i will appreciate. i do have a good understanding of mechanics i have rebuilt several motorbike engines before but have not tinkered around with car engines. thanks

forgotmyname

What gap did you set for the sparkplugs?

debtdebt

Do people still need to gap spark plugs nowadays?

watercoolednoob

did not change but they were the same as the old ones.

forgotmyname

debtdebt wrote: »

Do people still need to gap spark plugs nowadays?

In theory if you buy the right ones they come pre-gapped for the application. But how many check the FR6 sparkplug they have been given is a 0.7mm, 0.8mm, 1mm or 1.2mm gap?

Whose to say that package was not dropped which closed the gap or damaged it?

watercoolednoob

forgotmyname wrote: »

In theory if you buy the right ones they come pre-gapped for the application. But how many check the FR6 sparkplug they have been given is a 0.7mm, 0.8mm, 1mm or 1.2mm gap?

Whose to say that package was not dropped which closed the gap or damaged it?

thanks for the advise i will gap my plugs in future i did not have a feeler gauge. other than spark gap ( i dont see how this would cause these symptoms) what should i do from here.

reddwarf2002

You should check the sparkplug in cylinder 4 and see what colour it is - if black/sooty then it's likely to be excess fuelling. If it's grey/light coloured then it is running lean i.e. not enough fuel is getting through. But do compare all the spark plugs and you'll get a better idea whether it is restricted to just cylinder 4.

forgotmyname

Rarely see the plugs in that state these days. Seen some factory original 120k mile plugs from a 12 year old 1.6 Focus and they would have been dirtier left sitting on the shelf for a week.

original untouched plugs after 12 years, probably good for another 12 but they were changed anyway.

foxy-stoat

Try swapping coil packs around and spark plugs and see if it still mis-fires on nr 4.