misfire cylinder 1

veccyv6sri

hi new to site and have the above problem this has happened two weeks after I have changed both chains after the timing had slipped also did complete service new plugs oil/filter have checked coilpack and all is fine have even had it in at dealer and have suggested head removal to look inside as its something mechanical. this engine has done 28,410 from new any suggestions would be great

Dave_Gilbert

Crack In the head down the side of the spark plug?

I have heard of this a few times on the z22's

evocarlos

Dave Gilbert said:
Crack In the head down the side of the spark plug?

I have heard of this a few times on the z22's

its a z22yh dave they dont suffer with this as there flat type spark plugs 🙂

i would suspect coil pack break down but hard to say

Dave_Gilbert

Oh right. By bad. Well a coil pack will be alot cheaper to fix so great news.

veccyv6sri

Dave Gilbert said:
Oh right. By bad. Well a coil pack will be alot cheaper to fix so great news.

have been told by dealer its down on compression on that cylinder

Dave_Gilbert

hmmm, that could be a few different things causing that.
1;Lack of oil causing the rings to be overworked.

Old (worn) and weak rings.
Crack or opening in the head - but that doesn't necessarily mean water in the oil or oil in the water.
Cracked cylinder
Burned, warped or cracked valve(s).
Burned or cracked piston.
Cylinder worn or out of round.
Blown or leaky head gasket.
Sticky valve(s).
Broken or worn valve spring(s).
Bent/worn pushrod(s)
Worn camshaft, or a broken lobe on the cam.
Worn or bent rocker arm(s).
Collapsed lifter(s).
it could mean several things from damaged rings and cylinder walls to tiny cracks in the piston heads or even a sticking or weak overhead valve if they have them
Low compression either from valves or rings. You can do the test wet and dry. Check the lbs. dry and then give a little shot of oil in the plug hole and check the lbs. If the pressure goes up wet, then the rings are losing the pressure. If the pressure is the same wet or dry, then it's a good chance that it needs a valve job.
Answer this may be caused by burnt valves,worn piston rings,blown head gasket.

(copied from google) i ddo a compression test wet and dry if you can.

milo

@[deleted] aren't. U mister joy lol 😉

Dave_Gilbert

What worse case scenario?

I just googled what could cause low compression. Its probably nothing serious but you do have to panick some times like doing all the chains costing 350 when you only needed a new alternator hahaha

rushy

Is it just 1 it misses on? The most common fault/faults on the Z22YH is the HP pump or the Inlet manifold. Both can cause misfires. The HP pump will show a miss in both 1&3, dont ask me why 1 & 3 as I don't know lol, and the swirl flap problem can cause a miss in all if the bar if off or just one bore if an individuality swirl flap is at fault. A HP pump fault in many cases doesn't show a fault code for the specific pump fault but a misfire.

rushy

veccyv6sri said:
have been told by dealer its down on compression on that cylinder

Just noticed this reply. Could it be a damaged valve caused by the chain slip? Also have you double checked the chain is set up right?

veccyv6sri

hpfp replaced at time of chain replaced and I'll check chain when back from dealer

veccyv6sri

hi just got motor back from dealer and now have the readings for compression test cyl1 130psi,cyl2,3&4 245psi and with oil down cylinder it only improved slightly. any ideas

rushy

Damaged valve? @[deleted]

evocarlos

rushy said:
Damaged valve? @[deleted]

sounds like it