Help with Engine Stuttering

[Britastic]

Hi,

This is my first post on Pistonheads and I’m hoping that someone can help me with a problem that I have on my TVR Chimaera 450 2000/X-Reg .

When accelerating, all is OK up until about 3000rpm.
At this point the tachometer needle starts to “Flicker around wildly” between 3-4000 rpm and the engine starts to “Stutter” and loses power intermittently.
Once past 4000rpm all is OK, and similarly below 3000rpm is also OK.
The problem just occurs between 3-4000rpm.

I’ve got the latest Ecumate diagnostic tool & fault code reader.
I have checked with this, but there is no fault code showing.
I’ve also tried ECU Reset, but this had no effect.

Is there an “RPM Sensor” located somewhere on the Rover V8 Engine?
And could it be this part that’s causing the fault?

Any help would be appreciated.

[chrispitman]

First thought throttle pot got a worn spot. Test with a meter or that rover gauge software some of the others are using shows the sensor output to see what its doing.

[blitzracing]

Britastic said:

Hi,



At this point the tachometer needle starts to “Flicker around wildly” between 3-4000 rpm and the engine starts to “Stutter” and loses power intermittently.

Is there an “RPM Sensor” located somewhere on the Rover V8 Engine?
And could it be this part that’s causing the fault?

Any help would be appreciated.

The tacho uses the trigger from the coil to get its reading- so the fault is distributor pickup- ignition amp coil or coil supply. It would make sense the ECUmate wont pick this up, unless it reads RPM as its not an ECU fault.

[Britastic]

chrispitman said:

First thought throttle pot got a worn spot. Test with a meter or that rover gauge software some of the others are using shows the sensor output to see what its doing.

Hi,
Thanks for the reply, my first thought was the throttle potentiometer too.
But I had dismissed it because the fault is specific to the Rev's rather than throttle position.

[FlipFlopGriff]

Ignition amp seems the likely culprit. Worst case you end up with some spares if its not. Not expensive either.
FFG

[Britastic]

Hi,

Thanks for the help.
It seems that the Ignition Module & Ignition Coil are the main suspects.
I've ordered a new Module & Coil, but won't get them until middle of next week now.
I got both for less than £50, and they're very easy to fit.

Thanks