V70 T5. Engine light, misfires and then limp mode.

[Jimbug1024]

Swapped the coils packs back and the fault is back to Cyclinder 1 Misfire (ECM-3513) - as expected really.

Can anyone say why swapping the left-most (ie nearest the timing belt) coils moves the error from cylinder 1 to 3? I'd have thought it would be from 1 to 2??

Anyway, new coil pack on order an hopefully that's the end of it for now.

[pierremcalpine]

Originally Posted by Jimbug1024

Swapped the coil packs for the left-most 2 cylinders.
Reset the codes and car and let it run.

Got an error for cylinder 3.
I thought the cylinders were numbered 1 to 5, working away from the timing belt end. Is that incorrect?

In the meantime I didn't notice before that when it runs there's smoke coming up from behind the engine - not loads but just a bit. Was wondering/hoping this is just due to the non-firing cylinder.

You are correct. Smoke, ehe? Hmmm, cracked exhaust manifold?

[Jimbug1024]

One problem at a time...? That would be too convenient

New coil on order. Hoping that will be that done then I'll check for the smoke from the back of the engine - I imagine that'll be another thread.

[Jimbug1024]

Swapped plugs for cylinders 1 & 2.
Replaced coil for cylinder 1.

STILL getting Cylinder 1 mis-fire.


Which has confused me, as the problem moved when I swapped coils - albeit to an unexpected cylinder.

HT Leads?

Anyone else had this kind of weirdness. I thought this was going to be straightforward...

[Jimbug1024]

Reset all the codes and took it for a drive.

It ran rough, but over 2,500(ish) it smoothed out but the Engine Light started flashing.
Got it home and still only got the ECM-3503 and ECM-3513.

So... this has gone beyond me and I'll have to book it in.

Might have lost some oil so I'm wondering about oil leaking into the cylinder - head gasket?. At 165K on the clock and the faults only started after it's first long motorway in months - at a healthy motorway speed plus some progressive driving, so it was experiencing some "load" and the fault started while under acceleration although not "flooring it".

I'll post up the results so there's a record that might of use to others.
Might be after payday!

[VOLVOBOY]

Sounds more like a timing issue to me.
The DTC is a bit misleading. You think of coil pack and spark plug.
If swapping them around proves nothing or doesn`t make sense then check the wiring loom and earths. Bad earths cause a lot of weird things to happen.
It just may be that the plugs are firing but not at the right time. You said that it ran OK and then started to play up. That sounds like something electrical breaking down ( like the old HT leads used to when they got hot) or there`s a problem with timing advance and retard (VVT valve) .
What concerns me most is that unburnt fuel has passed over the Cat for a prolonged period . It could be trashed.

[VOLVOBOY]

P0350 to P0362 are coil pack trouble codes.
I think the problem is elsewhere.
Is it over or under fuelling ? can you smell fuel ?
Does the engine reach correct operating temp ?
Any air or vacuum leaks ?

As an aside you say there`s smoke up the back of the engine. Have you got crankcase pressure ? With engine running pull the dipstick up . If there`s a rush of air the breather system is probably blocked. Another method is a rubber glove over the oil filler . If it expands - not good. If it sucks in - good.
Dirty oil can crud up the VVT valve(s) causing them to get stuck or not operate correctly.

[Jimbug1024]

Multiple but related issues.

All spark plugs replaced.
All coil packs replaced.
Most of the wiring loom replaced.

Running like new


Thanks for all the feedback and comments.
It's been very educational.

[Tnel]

Hey there just picked up my c70 a few weeks ago and it started throwing a code for misfire on cylinder 4. it runs fine in normal driving conditions but certain points when in high rpms it stumbles and the light will flash for a minute and then return to regular illuminated. I just put in new plugs today it seemed to help a little but still same issues

1998 c70 2.3t5 manual trans 118 miles

[barrybritcher]

if you fitted a used wiring loom it'll prolly only last 6 months. get one from dave barton if you plan on keeping the car. (google)