I have just replaced the thermostat on my car (mk1 1.2 Sporting) and now the car has become 'jerky' when driving, as if its about to cut out.

I have read through a few other threads and someone had suggested changing the lambda sensor, but it could be tested by unplugging it first.

Where abouts in the engine bay is the plug ?

I have checked the HT leads and they seem ok, but is it possible that they could be damaged internally, with no visible signs externally ?

Thanks

its near the cat on the downpipe. you may need to removed the exhaust manifold heat shield to get to it - cant remember.

That is for the Lambda sensor itself , in the downpipe.

I take it is there that the ecu works out what the fuel mix required is.

yeh, theres a connector here to disconnect it to test

yup, lambda checks the emmissions to figure whether the engine is running rich/lean and ECU adjusts the mix accordingly.

Right so if I wanted to disconnect it I have to get under the car, or is there a plug in the engine bay also ??

you can probably reach it from under the bonnet, but as far as i know, the connector goes straight into the wiring loom to the ECU, so this would be the only place to disconnect.