2001 V70 XC AWD Turbo misfire cylinder and P0134 error?

Tneville29 · Post by **Tneville29** » 18 Oct 2015, 15:58

New to Volvos. I have a misfire code for cylinder 4 error as well as a P0134 error(O2 sensor no activity , bank 1, sensor 1) guessing the O2 front side is that error. Replaced the plug and coil on cylinder 4, still got both codes. I've heard a misfiring cylinder can ruin an O2 sensor, so I'm trying to tackle the misfire first. What else can cause a misfire, considering it's a new plug, boot and coil? Fuel injector? Ant and all hell is appreciated, even directing to a thread that covers this. I tried the search and it got all messed up. Tom.

Tneville29 · Post by **Tneville29** » 27 Oct 2015, 16:45

Throwing caution to the wind (after doing a ton of research), and going with the burnt exhaust valve on cylinder 4. Can someone direct me to a thread that covers the removal and installation (step by step with required tools) for a remanufactured head removal and replacement? (Throwing in a new timing belt and probably a water pump as well?). I know it's in here, just have no idea where to look. Thanx a bunch, Tom. This site came highly recommended. I hope it holds up to the reference.

Post by **abscate** » 28 Oct 2015, 09:12

Have you run a compression test on all cylinders Tom?

You want to run one both dry, and then with oil, to see if you can isolate valve from ring wear/ problems

I'll search for a good cylinder head thread in the VRD

mrscullini · Post by **mrscullini** » 30 Oct 2015, 07:38

haven't pulled the head on a p2, but the job on my '00 was pretty straight forward. would anticipate it's a little more difficult to access the back of the motor on the p2 just because of the body changes.

but before pulling the head, i would do as abscate recommends. i had to pull my head because i burned an intake valve. when this happened, the motor ran rough at idle, like it was running on 4 cylinders (which it basically was). i can't remember, but i don't think i had a cel. at higher revs, it ran OK, which makes sense. it could build and hold some compression at high revs.

when i did my compression test, i had 0 psi. i had a hole in my valve about 1/2 the size of a pencil eraser.

how many miles? have the o2 sensors been replaced? i wouldn't be too anxious to pull the head.