Changed the temp sensor today and all seemed well until it got warm and it seems the warmer it got the weaker the fuel mixture got until just before the fans came in it stopped altogether. It now runs very erratic when warm and is very difficult to keep running, if it stops it will not start until it has cooled down. Any ideas before I take it to a diagnostics garage?
A couple of possible problems:
- Fuel pressure too low so injectors doesn't supply necessary amount of fuel, lambda sensor should make up for that, but only intermittently. This is likely a defective pump or a fuel leak.
- Inlet temperature sensor bad too, if it reports the air temperature too low, then the computer miscalculates the fuel amount to a too-lean mixture
- Inlet vacuum sensor faulty or there is a leak in the hose from the inlet manifold
- Bad wires
I suggest you disconnect the water temp sensor until you have had it diagnosed.