Get your head around this :P

Okay,
Something I am trying to figure out.

Basically, I have on my dash a switch that bypasses the ECU coolant temp sensor. The guy I got the car off, said when it starts limping flick the switch and it stops.

Well, up until this evening it has never started limping. (I've had the car 3 weeks now)

I went to pull away from the lights, and it started limping badly. The car would go up to 2000rpm cut out, then fire back up to 2000rpm, never it would go any higher. But soon as I flicked this little switch, it stopped completely.
Anyone have any ideas why it does this?
The wiring on the car is not the best I have to admit. In the engine bay there are loose plugs everywhere (that I will upload pictures of so someone can tell me what they're for )

I dont know if it would have anything to do with the ignition timing as I set that up tonight as it was out a fair bit.

The guy said though, that it will only limp when the temperature is almost in the red. Well mine temp gauge has never gone near it, it sits nicely in the middle like it should.

Anywho, if anyone can get there head around it, then brilliant!

Sounds like it bypass the temp sensor to fool the ECU into a different fuel map.....

When engines warm up, the fuel map changes to ensure a decent burn and tries to keep emissions under control....if when yours gets to hot the fuel map changes and the engine falters....this little switch obviously bypasses the temp sensor and drops in a resistor to fool the ECU into a different map....

If I were you I'd checkout the temp issue as even though you have not had any overheats the previous owner obviously did from his comments....

I'll check out any overheating issues. Just difficult as its never once overheated for me.
The only other thing I can think of is water damage. The guy did say to me, the car has been everywhere, water has filled the inside of the car, its been up and over the windscreen. So maybe it could be a electrical problem with the ECU as they're under the drivers seat - if Im correct.