Hi all,
I've been trying to chase down a long term, extremely intermittent fault on my +8 - It occurs very infrequently and currently only after some harder (motorway type driving).
The issue is the engine will sometimes run really rough - possibly missing on one or more cylinders and then cut out when I stop. A reset of the ECU (remove/replace the red key) will usually get me going again. I have done all the usual checks and changes with no success. So I started to drive the car with a laptop connected and logging ECU data with Rover Gauge. Last weekend I think I finally caught the issue. Just before the engine cut out (as we approached a junction) the data shows the engine speed going to 5800rpm! It clearly didn't and the rev limiter would have cut in to prevent it going that high.
Following a bit of research I found there should be a 6K8 Resistor in line from the neg side of the coil to the ECU input pin for engine speed.
I took a look at the car and found two 6K8 resistors - both connected to the neg side of the coil.
The spade contacts all looked pretty manky and resistance measurements weren't as expected, so I cleaned them up and confirmed they then measured around 6K8 ohms. So this maybe the fix.
But I don't have any idea why there should be 2 resistors and the wiring doesn't seem to match anything I can find. I will continue to buzz out the wiring to see where it goes (White background blue stripe - one of the Resistors has a red sleeve over it as well.
Any advice or info would be most welcome.
Thanks
Kev
