Misfire 4-6k revs under load

[Tyre Smoke]

As it says really, under acceleration am getting a misfire intermittently. Sometimes only slightly, sometimes like the F1 traction control noise. No MIL light and only when fully warmed up.

Coil pack(s)?

[HarryW]

Sounds HT related/ weak or missing spark, could be a coil pack.

[Keithyboy]

HarryW said:

Sounds HT related/ weak or missing spark, could be a coil pack.

[Olly]

My money is on a coil pack as well.

(been there, done that & got the t-shirt)

[mxi933]

I had a bit of that too. One of the plug caps had worked loose. Pushed it back on. Back to normal again

[Tyre Smoke]

mxi933 said:

I had a bit of that too. One of the plug caps had worked loose. Pushed it back on. Back to normal again

I'll check later, hope that's all it is.

[HB]

feel at idle over the exhaust if it is even flow from bothe sides (odd/even) If it is not my guess is a throttle pot. If the car drowns in fuel, its likely.

[jonbarrett]

On mine it was the coil packs. Cases had slight cracks and moisture getting in. Probably cracked due to temperature cycling due to their hot position.

[Ron Fellows]

I used to get this when a throttle pot was packing in and I only got the MIL light if it was bad! Its the cheapest thing to replace and can be easily checked if you have the software. Try checking this before looking at leads or coils.

[PHILON]

I had a very similar problem with mine last year. Both the Coil Packs and the Leads were shorting out through their insulation.

I would recommend changing them both.

[PHILON]

I had a very similar problem with mine last year. Both the Coil Packs and the Leads were shorting out through their insulation.

I would recommend changing them both.

[Tyre Smoke]

Turned out it was a loose HT lead and an oiled plug. Discovered when it went to Dulford for its spanner check after the chassis rebuild. But they've now discovered its a bit flat 4k and more.

[marcus1970]

Tyre Smoke said:

As it says really, under acceleration am getting a misfire intermittently. Sometimes only slightly, sometimes like the F1 traction control noise. No MIL light and only when fully warmed up.

Coil pack(s)?

What's an 'F1 traction control noise'?

MB

[HarryW]

marcus1970 said:

Tyre Smoke said:

As it says really, under acceleration am getting a misfire intermittently. Sometimes only slightly, sometimes like the F1 traction control noise. No MIL light and only when fully warmed up.

Coil pack(s)?

What's an 'F1 traction control noise'?

MB

TC activation is normally by spark or fuel injector restricitons which then reduces the power to teh wheels, spark is generally the safer option. A missfire casued by a missing spark sound the same and causes stuttering (or did you not want the simple answer ).