Car only starts when cold. Would heat cause Crankcase position sensor to fail and not send fuel until it cools off??
I just had new sensor installed …..then car only starts when cold not when warmed up. Could the new sensor have been installed
incorrectly or did I get a defective new sensor????

 

Is there a reason you are linking the no start to the crank position sensor. ie only started giving trouble after changing it?
Have the fuel system air and temperature sensors been checked, more likely one of these.
.

 

Problem starting after warmed up began when new sensor was replaced. She starts fine when cold. We replaced fuel pumps, filters, strainers, relay. She also now backfires occasionally and never did before...….Did I get a bad sensor maybe or could it be installed wrong??

 

Can heat cause the sensor to malfunction???

 

How do you check and where are the fuel system air and temp sensors??

 

Assuming the 6 litre is same as the 5.3 both sensors on L/H bank, coolant sensor nearby to thermostat and air sensor on air cleaner inlet trumpet. I am not sure what the resistant values of these are meant to be. At least on 5.3 motors it is possible to mix the plugs up.
Doug just started a thread regarding coolant sensor may be helpful to you.

 

Was this the front sensor? Yes if its not functioning right it may start cold but die on warmup or otherwise fail to start while warm/hot. Did you install it yourself? Theres supposed to be a specific gap between the sensir if Im not mistaken.

I had the same issue 3 yrs ago, new sensor fixed this.

 

What is the specific gap on the sensor...?? It is my impression that it can only be installed in one way and no gap is to be considered.

 

Can someone confirm what Engine Code FF77 means for '94 XJS V12 6L???