Disco 1 V8 3.9 1996 won't start when cold

Asking for a friend...
His V8 does not start when cold. After a lot of trying, or when ambient temp is high - starts and runs normally.
Any ideas?

Cheers

Ady Gancz said:

Asking for a friend...
His V8 does not start when cold. After a lot of trying, or when ambient temp is high - starts and runs normally.
Any ideas?

Cheers

Click to expand...

dodgy temp sensor?

A Hotwire V8?

Maybe the temp sensor has failed and says the coolant temp is too warm, so it doesn't pump in enough fuel to start?

Find or buy a Rovergauge cable.

I've been told to try and unplug either the manifold temp sensor or the Lambda O2 sensor (one at a time) and see if that changes anything. Could anyone direct me to where these sensors are located?

Ady Gancz said:

I've been told to try and unplug either the manifold temp sensor or the Lambda O2 sensor (one at a time) and see if that changes anything. Could anyone direct me to where these sensors are located?

Click to expand...

The lambda O2 sensors will be on the exhausts just downstream of the cats.
The manifold temp semsor should be soemwhere on the inlet manifold, but I don't know as I have never looked that closely at my V8.
But on my TD5 the IAT sensor is in the inlet manifold.
But we could be talking about something as simple as the coolant temp sensor which will have to be in the coolant system somewhere.
I'd be very surprised if it was the O2 sensor(s).
Edit: Could be talking through my hat, just looked at the RAVE manual and we need to know if you have a MFI or SFI system. And the O2 sensors may be in front ot the carts not behind.
Other cars have both, obvs.

You could try the ECU coolant temp one - that would make it default to "cold" start mode (assuming the wiring is OK - again, with Rovergauge you could see what the ECU sees!)
It should be the black one, with the square "timer" plug on it.

You could try popping the idle hose off and dribble 1/2 a teaspoon of fuel in, then try to start it, and see if it's a fuelling thing.

If could still be a weird spark issue.