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Hi everyone, my name is Andrew, I'm glad to join your community, I've hoped in better circumstances but what can I say...
So my problem it's related to misfire, I'm getting misfire on cilinder 1, 3 and 4, sometimes only on 3, and 4.
So far I've tried :
New spark plugs, and ignition leeds
3 new coils on the problematic cilinders
Swapped the injectors from the good side
Tighten up a bit the rocker cover bolts
Took off the O2 sensors (absolutely nothing changes this)
I'll also attach pictures with my fuel trims @idle and 3700 rpm (But I don't know how accurate they are)
the misfire it's quite consistent, once I got rid of it when I took the battery off, drove the car for a while, but soon I got full throttle on it.. the misfire started again.
Also if it matters I have a 74 mm fixed pulley, and straight pipe, no secondary o2 sensors (downstream).
I'm thinking about the o2 more, because with them on and cold start, the car doesn't misfires. With them off starts misfiring straight away almost.
Unfortunately I have bad new's, or not.. I'll definitely need your advice..
But I think I blew the engine... I have a small scoring on one of the cilinder walls, it could be caused by some dirt...also.. but definitely not good.
I will attach a picture with the damage.
Also on that cilinder it's giving me 100psi( it was quite of a stupid compression test, only removed the coil packs and crank
it for a little bit.
What should I do, should I start saving money for re-sleeve the engine? I had this planned anyway.. but not so soon.
Did your plugs have oil on them when you pulled them? I would do a compression test just in case, but if they didn't have oil on them the scoring is probably ok?
I don't think the car will run well with removed O2 sensors, but you can try replacing them altogether. You can buy some off-brand ones just to save some money, but I have had my O2 sensors go bad and cause all kinds of misfires when everything else checked well.
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