• Registered users are encouraged to enable MFA/2FA to add an aditional layer of security to their account. More information can be found here: https://www.ncsc.gov.uk/collection/top-tips-for-staying-secure-online/activate-2-step-verification-on-your-email

Miss fire problem,teg type r.

Messages
17
Hello everyone, just a problem post to see if anyone can help, I'm having an issue with my car, to start with I fitted some tunner stage 3 cams with all the upgrades needed, the car ran great after tunning for a couple off weeks then it started with a miss fire after an lma snapped, so the head came back off,skimmed the head had it port polished and replaced all lma's with brand new ones, I then put the head back together and started it up for the first time after everything and the miss fire was still there but the car drove a pulled brill after 2500rpm, so I did a compression test,I then stripped the engine completely and replaced piston rings,bearings on the conrods, timming chain and tensioner,basically an overhaul, started it up for the first time again,it ran sweet for about 10secs then I heard the same noise from when the first lma snapped and it started to miss again,so switched it off straight away and took the rocker off and everything was good,engine turns over brilliant so we did a compression test again and on a cold engine all for cylinders where at 180psi so put it back together, miss fire is still there only ever so small, I took the car up the road and as before it clears at 2500. I've swapped all coil packs around and injectors and it seems to stay on cylinder 3 no matter what I do, I'm realy stumped and don't know where to go from here,any suggestions by you guys,thanks
 
Wild guess, assuming you've checked everything, chain slap when the cycle gets round to, "Bang," on cylinder 3.

Try turning the engine from the crank bolt and see what the chain is doing through the cycle.

Dialing in the exhaust cam with an adjustable cam gear would be the likely fix for chain slap in that case.

Probably something else, just what jumped into my head.
 
Well after a full rebuild off bottom end etc, I never checked the rockers and vtec engagement pins, cylinder 3 inlet was stuck in vtec giving me readings that I was down compression, cars running great now
 
Back
Top