850 2.0 20v N/A Misfire @103k

[CeeKay]

Hi Guys,

I was just looking for some advice.

My Rowing club's towing car has what was a small stutter, to intermittent misfire, to terminal misfire.

**Strange part**
- It seems to 'clear' itself sometimes, when opening up the throttle/doing a drag up a hill, that works in Sheffield, but not in Cambridge now (no hills!). Also, the engine needs to be warm.

- Also, after changing the clutch, the engine was on an angle for a few of days as it was a DIY job, and it cured it for the whole of the journey from Sheffield to Cambridge.

I've had it looked at by a mechanic, plugs, leads and dist cap are fine as the spark is fine. He diagnosed it as a sticky valve or a bad injector.

Also, one of the injectors clicks very loudly. Is this a sign of excessive wear?

When you inspect the plugs, a couple of the cylinders have quite sooty plugs. Is this likely to be knackered injectors with an unignitable spray or a sticky valve?

I am OK with cars, not great. I'm sure I would be able to change the injectors, and perhaps use an oil flush (Wynns) before the next change to help free the valve if it's that. Any tips in the meantime?

I have been using redex and stp etc, to little avail really. The only one that worked was STP fuel system cleaner, which says only to use it every 3k miles, and I haven't been able to find it for a while.

It's MOT isn't until 8th March, but as it is, it's unlikely to pass emissions, but otherwise it's a sound car!

Any help would be appreciated!

[lou]

Originally Posted by CeeKay

Hi Guys,

I was just looking for some advice.

My Rowing club's towing car has what was a small stutter, to intermittent misfire, to terminal misfire.

**Strange part**
- It seems to 'clear' itself sometimes, when opening up the throttle/doing a drag up a hill, that works in Sheffield, but not in Cambridge now (no hills!). Also, the engine needs to be warm.

- Also, after changing the clutch, the engine was on an angle for a few of days as it was a DIY job, and it cured it for the whole of the journey from Sheffield to Cambridge.

I've had it looked at by a mechanic, plugs, leads and dist cap are fine as the spark is fine. He diagnosed it as a sticky valve or a bad injector.

Also, one of the injectors clicks very loudly. Is this a sign of excessive wear?

When you inspect the plugs, a couple of the cylinders have quite sooty plugs. Is this likely to be knackered injectors with an unignitable spray or a sticky valve?

I am OK with cars, not great. I'm sure I would be able to change the injectors, and perhaps use an oil flush (Wynns) before the next change to help free the valve if it's that. Any tips in the meantime?

I have been using redex and stp etc, to little avail really. The only one that worked was STP fuel system cleaner, which says only to use it every 3k miles, and I haven't been able to find it for a while.

It's MOT isn't until 8th March, but as it is, it's unlikely to pass emissions, but otherwise it's a sound car!

Any help would be appreciated!

hope this helps.http://www.4secondsflat.com/plug_chart.html